customdata.c

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/*
* $Id: customdata.c 38866 2011-07-31 02:24:06Z nicholasbishop $
*
* ***** BEGIN GPL LICENSE BLOCK *****
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software  Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* The Original Code is Copyright (C) 2006 Blender Foundation.
* All rights reserved.
*
* The Original Code is: all of this file.
*
* Contributor(s): Ben Batt <benbatt@gmail.com>
*
* ***** END GPL LICENSE BLOCK *****
*
* Implementation of CustomData.
*
* BKE_customdata.h contains the function prototypes for this file.
*
*/

#include <math.h>
#include <string.h>
#include <assert.h>

#include "MEM_guardedalloc.h"

#include "DNA_meshdata_types.h"
#include "DNA_ID.h"

#include "BLI_blenlib.h"
#include "BLI_path_util.h"
#include "BLI_linklist.h"
#include "BLI_math.h"
#include "BLI_mempool.h"
#include "BLI_utildefines.h"

#include "BKE_customdata.h"
#include "BKE_customdata_file.h"
#include "BKE_global.h"
#include "BKE_main.h"
#include "BKE_utildefines.h"
#include "BKE_multires.h"

/* number of layers to add when growing a CustomData object */
#define CUSTOMDATA_GROW 5

/********************* Layer type information **********************/
typedef struct LayerTypeInfo {
        int size;          /* the memory size of one element of this layer's data */
        const char *structname;  /* name of the struct used, for file writing */
        int structnum;     /* number of structs per element, for file writing */
        const char *defaultname; /* default layer name */

        /* a function to copy count elements of this layer's data
         * (deep copy if appropriate)
         * if NULL, memcpy is used
         */
        void (*copy)(const void *source, void *dest, int count);

        /* a function to free any dynamically allocated components of this
         * layer's data (note the data pointer itself should not be freed)
         * size should be the size of one element of this layer's data (e.g.
         * LayerTypeInfo.size)
         */
        void (*free)(void *data, int count, int size);

        /* a function to interpolate between count source elements of this
         * layer's data and store the result in dest
         * if weights == NULL or sub_weights == NULL, they should default to 1
         *
         * weights gives the weight for each element in sources
         * sub_weights gives the sub-element weights for each element in sources
         *    (there should be (sub element count)^2 weights per element)
         * count gives the number of elements in sources
         */
        void (*interp)(void **sources, float *weights, float *sub_weights,
                                   int count, void *dest);

        /* a function to swap the data in corners of the element */
        void (*swap)(void *data, const int *corner_indices);

        /* a function to set a layer's data to default values. if NULL, the
           default is assumed to be all zeros */
        void (*set_default)(void *data, int count);

        /* a function to read data from a cdf file */
        int (*read)(CDataFile *cdf, void *data, int count);

        /* a function to write data to a cdf file */
        int (*write)(CDataFile *cdf, void *data, int count);

        /* a function to determine file size */
        size_t (*filesize)(CDataFile *cdf, void *data, int count);

        /* a function to validate layer contents depending on
         * sub-elements count
         */
        void (*validate)(void *source, int sub_elements);
} LayerTypeInfo;

static void layerCopy_mdeformvert(const void *source, void *dest,
                                                                  int count)
{
        int i, size = sizeof(MDeformVert);

        memcpy(dest, source, count * size);

        for(i = 0; i < count; ++i) {
                MDeformVert *dvert = (MDeformVert *)((char *)dest + i * size);

                if(dvert->totweight) {
                        MDeformWeight *dw = MEM_callocN(dvert->totweight * sizeof(*dw),
                                                                                        "layerCopy_mdeformvert dw");

                        memcpy(dw, dvert->dw, dvert->totweight * sizeof(*dw));
                        dvert->dw = dw;
                }
                else
                        dvert->dw = NULL;
        }
}

static void layerFree_mdeformvert(void *data, int count, int size)
{
        int i;

        for(i = 0; i < count; ++i) {
                MDeformVert *dvert = (MDeformVert *)((char *)data + i * size);

                if(dvert->dw) {
                        MEM_freeN(dvert->dw);
                        dvert->dw = NULL;
                        dvert->totweight = 0;
                }
        }
}

static void linklist_free_simple(void *link)
{
        MEM_freeN(link);
}

static void layerInterp_mdeformvert(void **sources, float *weights,
                                                                        float *UNUSED(sub_weights), int count, void *dest)
{
        MDeformVert *dvert = dest;
        LinkNode *dest_dw = NULL; /* a list of lists of MDeformWeight pointers */
        LinkNode *node;
        int i, j, totweight;

        if(count <= 0) return;

        /* build a list of unique def_nrs for dest */
        totweight = 0;
        for(i = 0; i < count; ++i) {
                MDeformVert *source = sources[i];
                float interp_weight = weights ? weights[i] : 1.0f;

                for(j = 0; j < source->totweight; ++j) {
                        MDeformWeight *dw = &source->dw[j];

                        for(node = dest_dw; node; node = node->next) {
                                MDeformWeight *tmp_dw = (MDeformWeight *)node->link;

                                if(tmp_dw->def_nr == dw->def_nr) {
                                        tmp_dw->weight += dw->weight * interp_weight;
                                        break;
                                }
                        }

                        /* if this def_nr is not in the list, add it */
                        if(!node) {
                                MDeformWeight *tmp_dw = MEM_callocN(sizeof(*tmp_dw),
                                                                                        "layerInterp_mdeformvert tmp_dw");
                                tmp_dw->def_nr = dw->def_nr;
                                tmp_dw->weight = dw->weight * interp_weight;
                                BLI_linklist_prepend(&dest_dw, tmp_dw);
                                totweight++;
                        }
                }
        }

        /* now we know how many unique deform weights there are, so realloc */
        if(dvert->dw) MEM_freeN(dvert->dw);

        if(totweight) {
                dvert->dw = MEM_callocN(sizeof(*dvert->dw) * totweight,
                                                                "layerInterp_mdeformvert dvert->dw");
                dvert->totweight = totweight;

                for(i = 0, node = dest_dw; node; node = node->next, ++i)
                        dvert->dw[i] = *((MDeformWeight *)node->link);
        }
        else
                memset(dvert, 0, sizeof(*dvert));

        BLI_linklist_free(dest_dw, linklist_free_simple);
}


static void layerInterp_msticky(void **sources, float *weights,
                                                                float *UNUSED(sub_weights), int count, void *dest)
{
        float co[2], w;
        MSticky *mst;
        int i;

        co[0] = co[1] = 0.0f;
        for(i = 0; i < count; i++) {
                w = weights ? weights[i] : 1.0f;
                mst = (MSticky*)sources[i];

                co[0] += w*mst->co[0];
                co[1] += w*mst->co[1];
        }

        mst = (MSticky*)dest;
        mst->co[0] = co[0];
        mst->co[1] = co[1];
}


static void layerCopy_tface(const void *source, void *dest, int count)
{
        const MTFace *source_tf = (const MTFace*)source;
        MTFace *dest_tf = (MTFace*)dest;
        int i;

        for(i = 0; i < count; ++i)
                dest_tf[i] = source_tf[i];
}

static void layerInterp_tface(void **sources, float *weights,
                                                          float *sub_weights, int count, void *dest)
{
        MTFace *tf = dest;
        int i, j, k;
        float uv[4][2];
        float *sub_weight;

        if(count <= 0) return;

        memset(uv, 0, sizeof(uv));

        sub_weight = sub_weights;
        for(i = 0; i < count; ++i) {
                float weight = weights ? weights[i] : 1;
                MTFace *src = sources[i];

                for(j = 0; j < 4; ++j) {
                        if(sub_weights) {
                                for(k = 0; k < 4; ++k, ++sub_weight) {
                                        float w = (*sub_weight) * weight;
                                        float *tmp_uv = src->uv[k];

                                        uv[j][0] += tmp_uv[0] * w;
                                        uv[j][1] += tmp_uv[1] * w;
                                }
                        } else {
                                uv[j][0] += src->uv[j][0] * weight;
                                uv[j][1] += src->uv[j][1] * weight;
                        }
                }
        }

        *tf = *(MTFace *)sources[0];
        for(j = 0; j < 4; ++j) {
                tf->uv[j][0] = uv[j][0];
                tf->uv[j][1] = uv[j][1];
        }
}

static void layerSwap_tface(void *data, const int *corner_indices)
{
        MTFace *tf = data;
        float uv[4][2];
        static const short pin_flags[4] =
                { TF_PIN1, TF_PIN2, TF_PIN3, TF_PIN4 };
        static const char sel_flags[4] =
                { TF_SEL1, TF_SEL2, TF_SEL3, TF_SEL4 };
        short unwrap = tf->unwrap & ~(TF_PIN1 | TF_PIN2 | TF_PIN3 | TF_PIN4);
        char flag = tf->flag & ~(TF_SEL1 | TF_SEL2 | TF_SEL3 | TF_SEL4);
        int j;

        for(j = 0; j < 4; ++j) {
                int source_index = corner_indices[j];

                uv[j][0] = tf->uv[source_index][0];
                uv[j][1] = tf->uv[source_index][1];

                // swap pinning flags around
                if(tf->unwrap & pin_flags[source_index]) {
                        unwrap |= pin_flags[j];
                }

                // swap selection flags around
                if(tf->flag & sel_flags[source_index]) {
                        flag |= sel_flags[j];
                }
        }

        memcpy(tf->uv, uv, sizeof(tf->uv));
        tf->unwrap = unwrap;
        tf->flag = flag;
}

static void layerDefault_tface(void *data, int count)
{
        static MTFace default_tf = {{{0, 0}, {1, 0}, {1, 1}, {0, 1}}, NULL,
                                                           0, 0, TF_DYNAMIC, 0, 0};
        MTFace *tf = (MTFace*)data;
        int i;

        for(i = 0; i < count; i++)
                tf[i] = default_tf;
}

static void layerCopy_origspace_face(const void *source, void *dest, int count)
{
        const OrigSpaceFace *source_tf = (const OrigSpaceFace*)source;
        OrigSpaceFace *dest_tf = (OrigSpaceFace*)dest;
        int i;

        for(i = 0; i < count; ++i)
                dest_tf[i] = source_tf[i];
}

static void layerInterp_origspace_face(void **sources, float *weights,
                                                          float *sub_weights, int count, void *dest)
{
        OrigSpaceFace *osf = dest;
        int i, j, k;
        float uv[4][2];
        float *sub_weight;

        if(count <= 0) return;

        memset(uv, 0, sizeof(uv));

        sub_weight = sub_weights;
        for(i = 0; i < count; ++i) {
                float weight = weights ? weights[i] : 1;
                OrigSpaceFace *src = sources[i];

                for(j = 0; j < 4; ++j) {
                        if(sub_weights) {
                                for(k = 0; k < 4; ++k, ++sub_weight) {
                                        float w = (*sub_weight) * weight;
                                        float *tmp_uv = src->uv[k];

                                        uv[j][0] += tmp_uv[0] * w;
                                        uv[j][1] += tmp_uv[1] * w;
                                }
                        } else {
                                uv[j][0] += src->uv[j][0] * weight;
                                uv[j][1] += src->uv[j][1] * weight;
                        }
                }
        }

        *osf = *(OrigSpaceFace *)sources[0];
        for(j = 0; j < 4; ++j) {
                osf->uv[j][0] = uv[j][0];
                osf->uv[j][1] = uv[j][1];
        }
}

static void layerSwap_origspace_face(void *data, const int *corner_indices)
{
        OrigSpaceFace *osf = data;
        float uv[4][2];
        int j;

        for(j = 0; j < 4; ++j) {
                uv[j][0] = osf->uv[corner_indices[j]][0];
                uv[j][1] = osf->uv[corner_indices[j]][1];
        }
        memcpy(osf->uv, uv, sizeof(osf->uv));
}

static void layerDefault_origspace_face(void *data, int count)
{
        static OrigSpaceFace default_osf = {{{0, 0}, {1, 0}, {1, 1}, {0, 1}}};
        OrigSpaceFace *osf = (OrigSpaceFace*)data;
        int i;

        for(i = 0; i < count; i++)
                osf[i] = default_osf;
}

static void layerSwap_mdisps(void *data, const int *ci)
{
        MDisps *s = data;
        float (*d)[3] = NULL;
        int corners, cornersize, S;

        if(s->disps) {
                int nverts= (ci[1] == 3) ? 4 : 3; /* silly way to know vertex count of face */
                corners= multires_mdisp_corners(s);
                cornersize= s->totdisp/corners;

                if(corners!=nverts) {
                        /* happens when face changed vertex count in edit mode
                           if it happened, just forgot displacement */

                        MEM_freeN(s->disps);
                        s->totdisp= (s->totdisp/corners)*nverts;
                        s->disps= MEM_callocN(s->totdisp*sizeof(float)*3, "mdisp swap");
                        return;
                }

                d= MEM_callocN(sizeof(float) * 3 * s->totdisp, "mdisps swap");

                for(S = 0; S < corners; S++)
                        memcpy(d + cornersize*S, s->disps + cornersize*ci[S], cornersize*3*sizeof(float));
                
                MEM_freeN(s->disps);
                s->disps= d;
        }
}

static void layerInterp_mdisps(void **sources, float *UNUSED(weights),
                                float *sub_weights, int count, void *dest)
{
        MDisps *d = dest;
        MDisps *s = NULL;
        int st, stl;
        int i, x, y;
        int side, S, dst_corners, src_corners;
        float crn_weight[4][2];
        float (*sw)[4] = (void*)sub_weights;
        float (*disps)[3], (*out)[3];

        /* happens when flipping normals of newly created mesh */
        if(!d->totdisp)
                return;

        s = sources[0];
        dst_corners = multires_mdisp_corners(d);
        src_corners = multires_mdisp_corners(s);

        if(sub_weights && count == 2 && src_corners == 3) {
                src_corners = multires_mdisp_corners(sources[1]);

                /* special case -- converting two triangles to quad */
                if(src_corners == 3 && dst_corners == 4) {
                        MDisps tris[2];
                        int vindex[4] = {0};

                        for(i = 0; i < 2; i++)
                                for(y = 0; y < 4; y++)
                                        for(x = 0; x < 4; x++)
                                                if(sw[x+i*4][y])
                                                        vindex[x] = y;

                        for(i = 0; i < 2; i++) {
                                float sw_m4[4][4] = {{0}};
                                int a = 7 & ~(1 << vindex[i*2] | 1 << vindex[i*2+1]);

                                sw_m4[0][vindex[i*2+1]] = 1;
                                sw_m4[1][vindex[i*2]] = 1;

                                for(x = 0; x < 3; x++)
                                        if(a & (1 << x))
                                                sw_m4[2][x] = 1;

                                tris[i] = *((MDisps*)sources[i]);
                                tris[i].disps = MEM_dupallocN(tris[i].disps);
                                layerInterp_mdisps(&sources[i], NULL, (float*)sw_m4, 1, &tris[i]);
                        }

                        mdisp_join_tris(d, &tris[0], &tris[1]);

                        for(i = 0; i < 2; i++)
                                MEM_freeN(tris[i].disps);

                        return;
                }
        }

        /* For now, some restrictions on the input */
        if(count != 1 || !sub_weights) {
                for(i = 0; i < d->totdisp; ++i)
                        zero_v3(d->disps[i]);

                return;
        }

        /* Initialize the destination */
        disps = MEM_callocN(3*d->totdisp*sizeof(float), "iterp disps");

        side = sqrt(d->totdisp / dst_corners);
        st = (side<<1)-1;
        stl = st - 1;

        sw= (void*)sub_weights;
        for(i = 0; i < 4; ++i) {
                crn_weight[i][0] = 0 * sw[i][0] + stl * sw[i][1] + stl * sw[i][2] + 0 * sw[i][3];
                crn_weight[i][1] = 0 * sw[i][0] + 0 * sw[i][1] + stl * sw[i][2] + stl * sw[i][3];
        }

        multires_mdisp_smooth_bounds(s);

        out = disps;
        for(S = 0; S < dst_corners; S++) {
                float base[2], axis_x[2], axis_y[2];

                mdisp_apply_weight(S, dst_corners, 0, 0, st, crn_weight, &base[0], &base[1]);
                mdisp_apply_weight(S, dst_corners, side-1, 0, st, crn_weight, &axis_x[0], &axis_x[1]);
                mdisp_apply_weight(S, dst_corners, 0, side-1, st, crn_weight, &axis_y[0], &axis_y[1]);

                sub_v2_v2(axis_x, base);
                sub_v2_v2(axis_y, base);
                normalize_v2(axis_x);
                normalize_v2(axis_y);

                for(y = 0; y < side; ++y) {
                        for(x = 0; x < side; ++x, ++out) {
                                int crn;
                                float face_u, face_v, crn_u, crn_v;

                                mdisp_apply_weight(S, dst_corners, x, y, st, crn_weight, &face_u, &face_v);
                                crn = mdisp_rot_face_to_quad_crn(src_corners, st, face_u, face_v, &crn_u, &crn_v);

                                old_mdisps_bilinear((*out), &s->disps[crn*side*side], side, crn_u, crn_v);
                                mdisp_flip_disp(crn, dst_corners, axis_x, axis_y, *out);
                        }
                }
        }

        MEM_freeN(d->disps);
        d->disps = disps;
}

static void layerCopy_mdisps(const void *source, void *dest, int count)
{
        int i;
        const MDisps *s = source;
        MDisps *d = dest;

        for(i = 0; i < count; ++i) {
                if(s[i].disps) {
                        d[i].disps = MEM_dupallocN(s[i].disps);
                        d[i].totdisp = s[i].totdisp;
                }
                else {
                        d[i].disps = NULL;
                        d[i].totdisp = 0;
                }
                
        }
}

static void layerValidate_mdisps(void *data, int sub_elements)
{
        MDisps *disps = data;
        if(disps->disps) {
                int corners = multires_mdisp_corners(disps);

                if(corners != sub_elements) {
                        MEM_freeN(disps->disps);
                        disps->totdisp = disps->totdisp / corners * sub_elements;
                        disps->disps = MEM_callocN(3*disps->totdisp*sizeof(float), "layerValidate_mdisps");
                }
        }
}

static void layerFree_mdisps(void *data, int count, int UNUSED(size))
{
        int i;
        MDisps *d = data;

        for(i = 0; i < count; ++i) {
                if(d[i].disps)
                        MEM_freeN(d[i].disps);
                d[i].disps = NULL;
                d[i].totdisp = 0;
        }
}

static int layerRead_mdisps(CDataFile *cdf, void *data, int count)
{
        MDisps *d = data;
        int i;

        for(i = 0; i < count; ++i) {
                if(!d[i].disps)
                        d[i].disps = MEM_callocN(sizeof(float)*3*d[i].totdisp, "mdisps read");

                if(!cdf_read_data(cdf, d[i].totdisp*3*sizeof(float), d[i].disps)) {
                        printf("failed to read multires displacement %d/%d %d\n", i, count, d[i].totdisp);
                        return 0;
                }
        }

        return 1;
}

static int layerWrite_mdisps(CDataFile *cdf, void *data, int count)
{
        MDisps *d = data;
        int i;

        for(i = 0; i < count; ++i) {
                if(!cdf_write_data(cdf, d[i].totdisp*3*sizeof(float), d[i].disps)) {
                        printf("failed to write multires displacement %d/%d %d\n", i, count, d[i].totdisp);
                        return 0;
                }
        }

        return 1;
}

static size_t layerFilesize_mdisps(CDataFile *UNUSED(cdf), void *data, int count)
{
        MDisps *d = data;
        size_t size = 0;
        int i;

        for(i = 0; i < count; ++i)
                size += d[i].totdisp*3*sizeof(float);

        return size;
}

/* --------- */

static void layerDefault_mloopcol(void *data, int count)
{
        static MLoopCol default_mloopcol = {255,255,255,255};
        MLoopCol *mlcol = (MLoopCol*)data;
        int i;
        for(i = 0; i < count; i++)
                mlcol[i] = default_mloopcol;

}

static void layerInterp_mloopcol(void **sources, float *weights,
                                float *sub_weights, int count, void *dest)
{
        MLoopCol *mc = dest;
        int i;
        float *sub_weight;
        struct {
                float a;
                float r;
                float g;
                float b;
        } col;
        col.a = col.r = col.g = col.b = 0;

        sub_weight = sub_weights;
        for(i = 0; i < count; ++i){
                float weight = weights ? weights[i] : 1;
                MLoopCol *src = sources[i];
                if(sub_weights){
                        col.a += src->a * (*sub_weight) * weight;
                        col.r += src->r * (*sub_weight) * weight;
                        col.g += src->g * (*sub_weight) * weight;
                        col.b += src->b * (*sub_weight) * weight;
                        sub_weight++;           
                } else {
                        col.a += src->a * weight;
                        col.r += src->r * weight;
                        col.g += src->g * weight;
                        col.b += src->b * weight;
                }
        }
        
        /* Subdivide smooth or fractal can cause problems without clamping
         * although weights should also not cause this situation */
        CLAMP(col.a, 0.0f, 255.0f);
        CLAMP(col.r, 0.0f, 255.0f);
        CLAMP(col.g, 0.0f, 255.0f);
        CLAMP(col.b, 0.0f, 255.0f);
        
        mc->a = (int)col.a;
        mc->r = (int)col.r;
        mc->g = (int)col.g;
        mc->b = (int)col.b;
}
static void layerInterp_mloopuv(void **sources, float *weights,
                                float *sub_weights, int count, void *dest)
{
        MLoopUV *mluv = dest;
        int i;
        float *sub_weight;
        struct {
                float u;
                float v;
        }uv;
        uv.u = uv.v = 0.0;

        sub_weight = sub_weights;
        for(i = 0; i < count; ++i){
                float weight = weights ? weights[i] : 1;
                MLoopUV *src = sources[i];
                if(sub_weights){
                        uv.u += src->uv[0] * (*sub_weight) * weight;
                        uv.v += src->uv[1] * (*sub_weight) * weight;
                        sub_weight++;           
                } else {
                        uv.u += src->uv[0] * weight;
                        uv.v += src->uv[1] * weight;
                }
        }
        mluv->uv[0] = uv.u;
        mluv->uv[1] = uv.v;
}

static void layerInterp_mcol(void **sources, float *weights,
                                                         float *sub_weights, int count, void *dest)
{
        MCol *mc = dest;
        int i, j, k;
        struct {
                float a;
                float r;
                float g;
                float b;
        } col[4];
        float *sub_weight;

        if(count <= 0) return;

        memset(col, 0, sizeof(col));
        
        sub_weight = sub_weights;
        for(i = 0; i < count; ++i) {
                float weight = weights ? weights[i] : 1;

                for(j = 0; j < 4; ++j) {
                        if(sub_weights) {
                                MCol *src = sources[i];
                                for(k = 0; k < 4; ++k, ++sub_weight, ++src) {
                                        col[j].a += src->a * (*sub_weight) * weight;
                                        col[j].r += src->r * (*sub_weight) * weight;
                                        col[j].g += src->g * (*sub_weight) * weight;
                                        col[j].b += src->b * (*sub_weight) * weight;
                                }
                        } else {
                                MCol *src = sources[i];
                                col[j].a += src[j].a * weight;
                                col[j].r += src[j].r * weight;
                                col[j].g += src[j].g * weight;
                                col[j].b += src[j].b * weight;
                        }
                }
        }

        for(j = 0; j < 4; ++j) {
                
                /* Subdivide smooth or fractal can cause problems without clamping
                 * although weights should also not cause this situation */
                CLAMP(col[j].a, 0.0f, 255.0f);
                CLAMP(col[j].r, 0.0f, 255.0f);
                CLAMP(col[j].g, 0.0f, 255.0f);
                CLAMP(col[j].b, 0.0f, 255.0f);
                
                mc[j].a = (int)col[j].a;
                mc[j].r = (int)col[j].r;
                mc[j].g = (int)col[j].g;
                mc[j].b = (int)col[j].b;
        }
}

static void layerSwap_mcol(void *data, const int *corner_indices)
{
        MCol *mcol = data;
        MCol col[4];
        int j;

        for(j = 0; j < 4; ++j)
                col[j] = mcol[corner_indices[j]];

        memcpy(mcol, col, sizeof(col));
}

static void layerDefault_mcol(void *data, int count)
{
        static MCol default_mcol = {255, 255, 255, 255};
        MCol *mcol = (MCol*)data;
        int i;

        for(i = 0; i < 4*count; i++)
                mcol[i] = default_mcol;
}



static const LayerTypeInfo LAYERTYPEINFO[CD_NUMTYPES] = {
        {sizeof(MVert), "MVert", 1, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MSticky), "MSticky", 1, NULL, NULL, NULL, layerInterp_msticky, NULL,
         NULL},
        {sizeof(MDeformVert), "MDeformVert", 1, NULL, layerCopy_mdeformvert,
         layerFree_mdeformvert, layerInterp_mdeformvert, NULL, NULL},
        {sizeof(MEdge), "MEdge", 1, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MFace), "MFace", 1, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MTFace), "MTFace", 1, "UVTex", layerCopy_tface, NULL,
         layerInterp_tface, layerSwap_tface, layerDefault_tface},
        /* 4 MCol structs per face */
        {sizeof(MCol)*4, "MCol", 4, "Col", NULL, NULL, layerInterp_mcol,
         layerSwap_mcol, layerDefault_mcol},
        {sizeof(int), "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
        /* 3 floats per normal vector */
        {sizeof(float)*3, "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(int), "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MFloatProperty), "MFloatProperty",1,"Float",NULL,NULL,NULL,NULL},
        {sizeof(MIntProperty), "MIntProperty",1,"Int",NULL,NULL,NULL,NULL},
        {sizeof(MStringProperty), "MStringProperty",1,"String",NULL,NULL,NULL,NULL},
        {sizeof(OrigSpaceFace), "OrigSpaceFace", 1, "UVTex", layerCopy_origspace_face, NULL,
         layerInterp_origspace_face, layerSwap_origspace_face, layerDefault_origspace_face},
        {sizeof(float)*3, "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MTexPoly), "MTexPoly", 1, "Face Texture", NULL, NULL, NULL, NULL, NULL},
        {sizeof(MLoopUV), "MLoopUV", 1, "UV coord", NULL, NULL, layerInterp_mloopuv, NULL, NULL},
        {sizeof(MLoopCol), "MLoopCol", 1, "Col", NULL, NULL, layerInterp_mloopcol, NULL, layerDefault_mloopcol},
        {sizeof(float)*4*4, "", 0, NULL, NULL, NULL, NULL, NULL, NULL},
        {sizeof(MDisps), "MDisps", 1, NULL, layerCopy_mdisps,
         layerFree_mdisps, layerInterp_mdisps, layerSwap_mdisps, NULL, layerRead_mdisps, layerWrite_mdisps,
         layerFilesize_mdisps, layerValidate_mdisps},
        {sizeof(MCol)*4, "MCol", 4, "WeightCol", NULL, NULL, layerInterp_mcol,
         layerSwap_mcol, layerDefault_mcol},
         {sizeof(MCol)*4, "MCol", 4, "IDCol", NULL, NULL, layerInterp_mcol,
         layerSwap_mcol, layerDefault_mcol},
         {sizeof(MCol)*4, "MCol", 4, "TexturedCol", NULL, NULL, layerInterp_mcol,
         layerSwap_mcol, layerDefault_mcol},
        {sizeof(float)*3, "", 0, NULL, NULL, NULL, NULL, NULL, NULL}
};

static const char *LAYERTYPENAMES[CD_NUMTYPES] = {
        /*   0-4 */ "CDMVert", "CDMSticky", "CDMDeformVert", "CDMEdge", "CDMFace",
        /*   5-9 */ "CDMTFace", "CDMCol", "CDOrigIndex", "CDNormal", "CDFlags",
        /* 10-14 */ "CDMFloatProperty", "CDMIntProperty","CDMStringProperty", "CDOrigSpace", "CDOrco",
        /* 15-19 */ "CDMTexPoly", "CDMLoopUV", "CDMloopCol", "CDTangent", "CDMDisps",
        /* 20-23 */"CDWeightMCol", "CDIDMCol", "CDTextureMCol", "CDClothOrco"
};

const CustomDataMask CD_MASK_BAREMESH =
        CD_MASK_MVERT | CD_MASK_MEDGE | CD_MASK_MFACE;
const CustomDataMask CD_MASK_MESH =
        CD_MASK_MVERT | CD_MASK_MEDGE | CD_MASK_MFACE |
        CD_MASK_MSTICKY | CD_MASK_MDEFORMVERT | CD_MASK_MTFACE | CD_MASK_MCOL |
        CD_MASK_PROP_FLT | CD_MASK_PROP_INT | CD_MASK_PROP_STR | CD_MASK_MDISPS;
const CustomDataMask CD_MASK_EDITMESH =
        CD_MASK_MSTICKY | CD_MASK_MDEFORMVERT | CD_MASK_MTFACE |
        CD_MASK_MCOL|CD_MASK_PROP_FLT | CD_MASK_PROP_INT | CD_MASK_PROP_STR | CD_MASK_MDISPS;
const CustomDataMask CD_MASK_DERIVEDMESH =
        CD_MASK_MSTICKY | CD_MASK_MDEFORMVERT | CD_MASK_MTFACE |
        CD_MASK_MCOL | CD_MASK_ORIGINDEX | CD_MASK_PROP_FLT | CD_MASK_PROP_INT | CD_MASK_CLOTH_ORCO |
        CD_MASK_PROP_STR | CD_MASK_ORIGSPACE | CD_MASK_ORCO | CD_MASK_TANGENT | CD_MASK_WEIGHT_MCOL;
const CustomDataMask CD_MASK_BMESH = 
        CD_MASK_MSTICKY | CD_MASK_MDEFORMVERT | CD_MASK_PROP_FLT | CD_MASK_PROP_INT | CD_MASK_PROP_STR;
const CustomDataMask CD_MASK_FACECORNERS =
        CD_MASK_MTFACE | CD_MASK_MCOL | CD_MASK_MTEXPOLY | CD_MASK_MLOOPUV |
        CD_MASK_MLOOPCOL;


static const LayerTypeInfo *layerType_getInfo(int type)
{
        if(type < 0 || type >= CD_NUMTYPES) return NULL;

        return &LAYERTYPEINFO[type];
}

static const char *layerType_getName(int type)
{
        if(type < 0 || type >= CD_NUMTYPES) return NULL;

        return LAYERTYPENAMES[type];
}

/********************* CustomData functions *********************/
static void customData_update_offsets(CustomData *data);

static CustomDataLayer *customData_add_layer__internal(CustomData *data,
        int type, int alloctype, void *layerdata, int totelem, const char *name);

void CustomData_merge(const struct CustomData *source, struct CustomData *dest,
                                          CustomDataMask mask, int alloctype, int totelem)
{
        /*const LayerTypeInfo *typeInfo;*/
        CustomDataLayer *layer, *newlayer;
        int i, type, number = 0, lasttype = -1, lastactive = 0, lastrender = 0, lastclone = 0, lastmask = 0, lastflag = 0;

        for(i = 0; i < source->totlayer; ++i) {
                layer = &source->layers[i];
                /*typeInfo = layerType_getInfo(layer->type);*/ /*UNUSED*/

                type = layer->type;

                if (type != lasttype) {
                        number = 0;
                        lastactive = layer->active;
                        lastrender = layer->active_rnd;
                        lastclone = layer->active_clone;
                        lastmask = layer->active_mask;
                        lasttype = type;
                        lastflag = layer->flag;
                }
                else
                        number++;

                if(lastflag & CD_FLAG_NOCOPY) continue;
                else if(!((int)mask & (int)(1 << (int)type))) continue;
                else if(number < CustomData_number_of_layers(dest, type)) continue;

                if((alloctype == CD_ASSIGN) && (lastflag & CD_FLAG_NOFREE))
                        newlayer = customData_add_layer__internal(dest, type, CD_REFERENCE,
                                layer->data, totelem, layer->name);
                else
                        newlayer = customData_add_layer__internal(dest, type, alloctype,
                                layer->data, totelem, layer->name);
                
                if(newlayer) {
                        newlayer->active = lastactive;
                        newlayer->active_rnd = lastrender;
                        newlayer->active_clone = lastclone;
                        newlayer->active_mask = lastmask;
                        newlayer->flag |= lastflag & (CD_FLAG_EXTERNAL|CD_FLAG_IN_MEMORY);
                }
        }
}

void CustomData_copy(const struct CustomData *source, struct CustomData *dest,
                                         CustomDataMask mask, int alloctype, int totelem)
{
        memset(dest, 0, sizeof(*dest));

        if(source->external)
                dest->external= MEM_dupallocN(source->external);

        CustomData_merge(source, dest, mask, alloctype, totelem);
}

static void customData_free_layer__internal(CustomDataLayer *layer, int totelem)
{
        const LayerTypeInfo *typeInfo;

        if(!(layer->flag & CD_FLAG_NOFREE) && layer->data) {
                typeInfo = layerType_getInfo(layer->type);

                if(typeInfo->free)
                        typeInfo->free(layer->data, totelem, typeInfo->size);

                if(layer->data)
                        MEM_freeN(layer->data);
        }
}

static void CustomData_external_free(CustomData *data)
{
        if(data->external) {
                MEM_freeN(data->external);
                data->external= NULL;
        }
}

void CustomData_free(CustomData *data, int totelem)
{
        int i;

        for(i = 0; i < data->totlayer; ++i)
                customData_free_layer__internal(&data->layers[i], totelem);

        if(data->layers)
                MEM_freeN(data->layers);
        
        CustomData_external_free(data);
        
        memset(data, 0, sizeof(*data));
}

static void customData_update_offsets(CustomData *data)
{
        const LayerTypeInfo *typeInfo;
        int i, offset = 0;

        for(i = 0; i < data->totlayer; ++i) {
                typeInfo = layerType_getInfo(data->layers[i].type);

                data->layers[i].offset = offset;
                offset += typeInfo->size;
        }

        data->totsize = offset;
}

int CustomData_get_layer_index(const CustomData *data, int type)
{
        int i; 

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return i;

        return -1;
}

int CustomData_get_named_layer_index(const CustomData *data, int type, const char *name)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type && strcmp(data->layers[i].name, name)==0)
                        return i;

        return -1;
}

int CustomData_get_active_layer_index(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return i + data->layers[i].active;

        return -1;
}

int CustomData_get_render_layer_index(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return i + data->layers[i].active_rnd;

        return -1;
}

int CustomData_get_clone_layer_index(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return i + data->layers[i].active_clone;

        return -1;
}

int CustomData_get_stencil_layer_index(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return i + data->layers[i].active_mask;

        return -1;
}

int CustomData_get_active_layer(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return data->layers[i].active;

        return -1;
}

int CustomData_get_render_layer(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return data->layers[i].active_rnd;

        return -1;
}

int CustomData_get_clone_layer(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return data->layers[i].active_clone;

        return -1;
}

int CustomData_get_stencil_layer(const CustomData *data, int type)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        return data->layers[i].active_mask;

        return -1;
}

void CustomData_set_layer_active(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active = n;
}

void CustomData_set_layer_render(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_rnd = n;
}

void CustomData_set_layer_clone(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_clone = n;
}

void CustomData_set_layer_stencil(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_mask = n;
}

/* for using with an index from CustomData_get_active_layer_index and CustomData_get_render_layer_index */
void CustomData_set_layer_active_index(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active = n-i;
}

void CustomData_set_layer_render_index(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_rnd = n-i;
}

void CustomData_set_layer_clone_index(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_clone = n-i;
}

void CustomData_set_layer_stencil_index(CustomData *data, int type, int n)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].active_mask = n-i;
}

void CustomData_set_layer_flag(struct CustomData *data, int type, int flag)
{
        int i;

        for(i=0; i < data->totlayer; ++i)
                if(data->layers[i].type == type)
                        data->layers[i].flag |= flag;
}

static int customData_resize(CustomData *data, int amount)
{
        CustomDataLayer *tmp = MEM_callocN(sizeof(*tmp)*(data->maxlayer + amount),
                                                                           "CustomData->layers");
        if(!tmp) return 0;

        data->maxlayer += amount;
        if (data->layers) {
                memcpy(tmp, data->layers, sizeof(*tmp) * data->totlayer);
                MEM_freeN(data->layers);
        }
        data->layers = tmp;

        return 1;
}

static CustomDataLayer *customData_add_layer__internal(CustomData *data,
        int type, int alloctype, void *layerdata, int totelem, const char *name)
{
        const LayerTypeInfo *typeInfo= layerType_getInfo(type);
        int size = typeInfo->size * totelem, flag = 0, index = data->totlayer;
        void *newlayerdata;

        if (!typeInfo->defaultname && CustomData_has_layer(data, type))
                return &data->layers[CustomData_get_layer_index(data, type)];

        if((alloctype == CD_ASSIGN) || (alloctype == CD_REFERENCE)) {
                newlayerdata = layerdata;
        }
        else {
                newlayerdata = MEM_callocN(size, layerType_getName(type));
                if(!newlayerdata)
                        return NULL;
        }

        if (alloctype == CD_DUPLICATE) {
                if(typeInfo->copy)
                        typeInfo->copy(layerdata, newlayerdata, totelem);
                else
                        memcpy(newlayerdata, layerdata, size);
        }
        else if (alloctype == CD_DEFAULT) {
                if(typeInfo->set_default)
                        typeInfo->set_default((char*)newlayerdata, totelem);
        }
        else if (alloctype == CD_REFERENCE)
                flag |= CD_FLAG_NOFREE;

        if(index >= data->maxlayer) {
                if(!customData_resize(data, CUSTOMDATA_GROW)) {
                        if(newlayerdata != layerdata)
                                MEM_freeN(newlayerdata);
                        return NULL;
                }
        }
        
        data->totlayer++;

        /* keep layers ordered by type */
        for( ; index > 0 && data->layers[index - 1].type > type; --index)
                data->layers[index] = data->layers[index - 1];

        data->layers[index].type = type;
        data->layers[index].flag = flag;
        data->layers[index].data = newlayerdata;
        if(name || (name=typeInfo->defaultname)) {
                BLI_strncpy(data->layers[index].name, name, 32);
                CustomData_set_layer_unique_name(data, index);
        }
        else
                data->layers[index].name[0] = '\0';

        if(index > 0 && data->layers[index-1].type == type) {
                data->layers[index].active = data->layers[index-1].active;
                data->layers[index].active_rnd = data->layers[index-1].active_rnd;
                data->layers[index].active_clone = data->layers[index-1].active_clone;
                data->layers[index].active_mask = data->layers[index-1].active_mask;
        } else {
                data->layers[index].active = 0;
                data->layers[index].active_rnd = 0;
                data->layers[index].active_clone = 0;
                data->layers[index].active_mask = 0;
        }
        
        customData_update_offsets(data);

        return &data->layers[index];
}

void *CustomData_add_layer(CustomData *data, int type, int alloctype,
                                                   void *layerdata, int totelem)
{
        CustomDataLayer *layer;
        const LayerTypeInfo *typeInfo= layerType_getInfo(type);
        
        layer = customData_add_layer__internal(data, type, alloctype, layerdata,
                                                                                   totelem, typeInfo->defaultname);

        if(layer)
                return layer->data;

        return NULL;
}

/*same as above but accepts a name*/
void *CustomData_add_layer_named(CustomData *data, int type, int alloctype,
                                                   void *layerdata, int totelem, const char *name)
{
        CustomDataLayer *layer;
        
        layer = customData_add_layer__internal(data, type, alloctype, layerdata,
                                                                                   totelem, name);

        if(layer)
                return layer->data;

        return NULL;
}


int CustomData_free_layer(CustomData *data, int type, int totelem, int index)
{
        int i;
        
        if (index < 0) return 0;

        customData_free_layer__internal(&data->layers[index], totelem);

        for (i=index+1; i < data->totlayer; ++i)
                data->layers[i-1] = data->layers[i];

        data->totlayer--;

        /* if layer was last of type in array, set new active layer */
        if ((index >= data->totlayer) || (data->layers[index].type != type)) {
                i = CustomData_get_layer_index(data, type);
                
                if (i >= 0)
                        for (; i < data->totlayer && data->layers[i].type == type; i++) {
                                data->layers[i].active--;
                                data->layers[i].active_rnd--;
                                data->layers[i].active_clone--;
                                data->layers[i].active_mask--;
                        }
        }

        if (data->totlayer <= data->maxlayer-CUSTOMDATA_GROW)
                customData_resize(data, -CUSTOMDATA_GROW);

        customData_update_offsets(data);

        return 1;
}

int CustomData_free_layer_active(CustomData *data, int type, int totelem)
{
        int index = 0;
        index = CustomData_get_active_layer_index(data, type);
        if (index < 0) return 0;
        return CustomData_free_layer(data, type, totelem, index);
}


void CustomData_free_layers(CustomData *data, int type, int totelem)
{
        while (CustomData_has_layer(data, type))
                CustomData_free_layer_active(data, type, totelem);
}

int CustomData_has_layer(const CustomData *data, int type)
{
        return (CustomData_get_layer_index(data, type) != -1);
}

int CustomData_number_of_layers(const CustomData *data, int type)
{
        int i, number = 0;

        for(i = 0; i < data->totlayer; i++)
                if(data->layers[i].type == type)
                        number++;
        
        return number;
}

void *CustomData_duplicate_referenced_layer(struct CustomData *data, int type)
{
        CustomDataLayer *layer;
        int layer_index;

        /* get the layer index of the first layer of type */
        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return NULL;

        layer = &data->layers[layer_index];

        if (layer->flag & CD_FLAG_NOFREE) {
                layer->data = MEM_dupallocN(layer->data);
                layer->flag &= ~CD_FLAG_NOFREE;
        }

        return layer->data;
}

void *CustomData_duplicate_referenced_layer_named(struct CustomData *data,
                                                                                                  int type, const char *name)
{
        CustomDataLayer *layer;
        int layer_index;

        /* get the layer index of the desired layer */
        layer_index = CustomData_get_named_layer_index(data, type, name);
        if(layer_index < 0) return NULL;

        layer = &data->layers[layer_index];

        if (layer->flag & CD_FLAG_NOFREE) {
                layer->data = MEM_dupallocN(layer->data);
                layer->flag &= ~CD_FLAG_NOFREE;
        }

        return layer->data;
}

void CustomData_free_temporary(CustomData *data, int totelem)
{
        CustomDataLayer *layer;
        int i, j;

        for(i = 0, j = 0; i < data->totlayer; ++i) {
                layer = &data->layers[i];

                if (i != j)
                        data->layers[j] = data->layers[i];

                if ((layer->flag & CD_FLAG_TEMPORARY) == CD_FLAG_TEMPORARY)
                        customData_free_layer__internal(layer, totelem);
                else
                        j++;
        }

        data->totlayer = j;

        if(data->totlayer <= data->maxlayer-CUSTOMDATA_GROW)
                customData_resize(data, -CUSTOMDATA_GROW);

        customData_update_offsets(data);
}

void CustomData_set_only_copy(const struct CustomData *data,
                                                          CustomDataMask mask)
{
        int i;

        for(i = 0; i < data->totlayer; ++i)
                if(!((int)mask & (int)(1 << (int)data->layers[i].type)))
                        data->layers[i].flag |= CD_FLAG_NOCOPY;
}

void CustomData_copy_data(const CustomData *source, CustomData *dest,
                                                  int source_index, int dest_index, int count)
{
        const LayerTypeInfo *typeInfo;
        int src_i, dest_i;
        int src_offset;
        int dest_offset;

        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        char *src_data = source->layers[src_i].data;
                        char *dest_data = dest->layers[dest_i].data;

                        typeInfo = layerType_getInfo(source->layers[src_i].type);

                        src_offset = source_index * typeInfo->size;
                        dest_offset = dest_index * typeInfo->size;

                        if(typeInfo->copy)
                                typeInfo->copy(src_data + src_offset,
                                                                dest_data + dest_offset,
                                                                count);
                        else
                                memcpy(dest_data + dest_offset,
                                           src_data + src_offset,
                                           count * typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }
}

void CustomData_free_elem(CustomData *data, int index, int count)
{
        int i;
        const LayerTypeInfo *typeInfo;

        for(i = 0; i < data->totlayer; ++i) {
                if(!(data->layers[i].flag & CD_FLAG_NOFREE)) {
                        typeInfo = layerType_getInfo(data->layers[i].type);

                        if(typeInfo->free) {
                                int offset = typeInfo->size * index;

                                typeInfo->free((char *)data->layers[i].data + offset,
                                                           count, typeInfo->size);
                        }
                }
        }
}

#define SOURCE_BUF_SIZE 100

void CustomData_interp(const CustomData *source, CustomData *dest,
                                           int *src_indices, float *weights, float *sub_weights,
                                           int count, int dest_index)
{
        int src_i, dest_i;
        int dest_offset;
        int j;
        void *source_buf[SOURCE_BUF_SIZE];
        void **sources = source_buf;

        /* slow fallback in case we're interpolating a ridiculous number of
         * elements
         */
        if(count > SOURCE_BUF_SIZE)
                sources = MEM_callocN(sizeof(*sources) * count,
                                                          "CustomData_interp sources");

        /* interpolates a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {
                const LayerTypeInfo *typeInfo= layerType_getInfo(source->layers[src_i].type);
                if(!typeInfo->interp) continue;

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        void *src_data = source->layers[src_i].data;

                        for(j = 0; j < count; ++j)
                                sources[j] = (char *)src_data
                                                         + typeInfo->size * src_indices[j];

                        dest_offset = dest_index * typeInfo->size;

                        typeInfo->interp(sources, weights, sub_weights, count,
                                                   (char *)dest->layers[dest_i].data + dest_offset);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }

        if(count > SOURCE_BUF_SIZE) MEM_freeN(sources);
}

void CustomData_swap(struct CustomData *data, int index, const int *corner_indices)
{
        const LayerTypeInfo *typeInfo;
        int i;

        for(i = 0; i < data->totlayer; ++i) {
                typeInfo = layerType_getInfo(data->layers[i].type);

                if(typeInfo->swap) {
                        int offset = typeInfo->size * index;

                        typeInfo->swap((char *)data->layers[i].data + offset, corner_indices);
                }
        }
}

void *CustomData_get(const CustomData *data, int index, int type)
{
        int offset;
        int layer_index;
        
        /* get the layer index of the active layer of type */
        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return NULL;

        /* get the offset of the desired element */
        offset = layerType_getInfo(type)->size * index;

        return (char *)data->layers[layer_index].data + offset;
}

void *CustomData_get_layer(const CustomData *data, int type)
{
        /* get the layer index of the active layer of type */
        int layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return data->layers[layer_index].data;
}

void *CustomData_get_layer_n(const CustomData *data, int type, int n)
{
        /* get the layer index of the active layer of type */
        int layer_index = CustomData_get_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return data->layers[layer_index+n].data;
}

void *CustomData_get_layer_named(const struct CustomData *data, int type,
                                                                 const char *name)
{
        int layer_index = CustomData_get_named_layer_index(data, type, name);
        if(layer_index < 0) return NULL;

        return data->layers[layer_index].data;
}

void *CustomData_set_layer(const CustomData *data, int type, void *ptr)
{
        /* get the layer index of the first layer of type */
        int layer_index = CustomData_get_active_layer_index(data, type);

        if(layer_index < 0) return NULL;

        data->layers[layer_index].data = ptr;

        return ptr;
}

void *CustomData_set_layer_n(const struct CustomData *data, int type, int n, void *ptr)
{
        /* get the layer index of the first layer of type */
        int layer_index = CustomData_get_layer_index(data, type);
        if(layer_index < 0) return NULL;

        data->layers[layer_index+n].data = ptr;

        return ptr;
}

void CustomData_set(const CustomData *data, int index, int type, void *source)
{
        void *dest = CustomData_get(data, index, type);
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        if(!dest) return;

        if(typeInfo->copy)
                typeInfo->copy(source, dest, 1);
        else
                memcpy(dest, source, typeInfo->size);
}

/* EditMesh functions */

void CustomData_em_free_block(CustomData *data, void **block)
{
        const LayerTypeInfo *typeInfo;
        int i;

        if(!*block) return;

        for(i = 0; i < data->totlayer; ++i) {
                if(!(data->layers[i].flag & CD_FLAG_NOFREE)) {
                        typeInfo = layerType_getInfo(data->layers[i].type);

                        if(typeInfo->free) {
                                int offset = data->layers[i].offset;
                                typeInfo->free((char*)*block + offset, 1, typeInfo->size);
                        }
                }
        }

        MEM_freeN(*block);
        *block = NULL;
}

static void CustomData_em_alloc_block(CustomData *data, void **block)
{
        /* TODO: optimize free/alloc */

        if (*block)
                CustomData_em_free_block(data, block);

        if (data->totsize > 0)
                *block = MEM_callocN(data->totsize, "CustomData EM block");
        else
                *block = NULL;
}

void CustomData_em_copy_data(const CustomData *source, CustomData *dest,
                                                        void *src_block, void **dest_block)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i;

        if (!*dest_block)
                CustomData_em_alloc_block(dest, dest_block);
        
        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type &&
                        strcmp(dest->layers[dest_i].name, source->layers[src_i].name) == 0) {
                        char *src_data = (char*)src_block + source->layers[src_i].offset;
                        char *dest_data = (char*)*dest_block + dest->layers[dest_i].offset;

                        typeInfo = layerType_getInfo(source->layers[src_i].type);

                        if(typeInfo->copy)
                                typeInfo->copy(src_data, dest_data, 1);
                        else
                                memcpy(dest_data, src_data, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }
}

void CustomData_em_validate_data(CustomData *data, void *block, int sub_elements)
{
        int i;
        for(i = 0; i < data->totlayer; i++) {
                const LayerTypeInfo *typeInfo = layerType_getInfo(data->layers[i].type);
                char *leayer_data = (char*)block + data->layers[i].offset;

                if(typeInfo->validate)
                        typeInfo->validate(leayer_data, sub_elements);
        }
}

void *CustomData_em_get(const CustomData *data, void *block, int type)
{
        int layer_index;
        
        /* get the layer index of the first layer of type */
        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return (char *)block + data->layers[layer_index].offset;
}

void *CustomData_em_get_n(const CustomData *data, void *block, int type, int n)
{
        int layer_index;
        
        /* get the layer index of the first layer of type */
        layer_index = CustomData_get_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return (char *)block + data->layers[layer_index+n].offset;
}

void CustomData_em_set(CustomData *data, void *block, int type, void *source)
{
        void *dest = CustomData_em_get(data, block, type);
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        if(!dest) return;

        if(typeInfo->copy)
                typeInfo->copy(source, dest, 1);
        else
                memcpy(dest, source, typeInfo->size);
}

void CustomData_em_set_n(CustomData *data, void *block, int type, int n, void *source)
{
        void *dest = CustomData_em_get_n(data, block, type, n);
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        if(!dest) return;

        if(typeInfo->copy)
                typeInfo->copy(source, dest, 1);
        else
                memcpy(dest, source, typeInfo->size);
}

void CustomData_em_interp(CustomData *data, void **src_blocks, float *weights,
                                                  float *sub_weights, int count, void *dest_block)
{
        int i, j;
        void *source_buf[SOURCE_BUF_SIZE];
        void **sources = source_buf;

        /* slow fallback in case we're interpolating a ridiculous number of
         * elements
         */
        if(count > SOURCE_BUF_SIZE)
                sources = MEM_callocN(sizeof(*sources) * count,
                                                          "CustomData_interp sources");

        /* interpolates a layer at a time */
        for(i = 0; i < data->totlayer; ++i) {
                CustomDataLayer *layer = &data->layers[i];
                const LayerTypeInfo *typeInfo = layerType_getInfo(layer->type);

                if(typeInfo->interp) {
                        for(j = 0; j < count; ++j)
                                sources[j] = (char *)src_blocks[j] + layer->offset;

                        typeInfo->interp(sources, weights, sub_weights, count,
                                                          (char *)dest_block + layer->offset);
                }
        }

        if(count > SOURCE_BUF_SIZE) MEM_freeN(sources);
}

void CustomData_em_set_default(CustomData *data, void **block)
{
        const LayerTypeInfo *typeInfo;
        int i;

        if (!*block)
                CustomData_em_alloc_block(data, block);

        for(i = 0; i < data->totlayer; ++i) {
                int offset = data->layers[i].offset;

                typeInfo = layerType_getInfo(data->layers[i].type);

                if(typeInfo->set_default)
                        typeInfo->set_default((char*)*block + offset, 1);
        }
}

void CustomData_to_em_block(const CustomData *source, CustomData *dest,
                                                        int src_index, void **dest_block)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i, src_offset;

        if (!*dest_block)
                CustomData_em_alloc_block(dest, dest_block);
        
        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        int offset = dest->layers[dest_i].offset;
                        char *src_data = source->layers[src_i].data;
                        char *dest_data = (char*)*dest_block + offset;

                        typeInfo = layerType_getInfo(dest->layers[dest_i].type);
                        src_offset = src_index * typeInfo->size;

                        if(typeInfo->copy)
                                typeInfo->copy(src_data + src_offset, dest_data, 1);
                        else
                                memcpy(dest_data, src_data + src_offset, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }
}

void CustomData_from_em_block(const CustomData *source, CustomData *dest,
                                                          void *src_block, int dest_index)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i, dest_offset;

        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        int offset = source->layers[src_i].offset;
                        char *src_data = (char*)src_block + offset;
                        char *dest_data = dest->layers[dest_i].data;

                        typeInfo = layerType_getInfo(dest->layers[dest_i].type);
                        dest_offset = dest_index * typeInfo->size;

                        if(typeInfo->copy)
                                typeInfo->copy(src_data, dest_data + dest_offset, 1);
                        else
                                memcpy(dest_data + dest_offset, src_data, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }

}

/*Bmesh functions*/
/*needed to convert to/from different face reps*/
void CustomData_to_bmeshpoly(CustomData *fdata, CustomData *pdata, CustomData *ldata)
{
        int i;
        for(i=0; i < fdata->totlayer; i++){
                if(fdata->layers[i].type == CD_MTFACE){
                        CustomData_add_layer(pdata, CD_MTEXPOLY, CD_CALLOC, &(fdata->layers[i].name), 0);
                        CustomData_add_layer(ldata, CD_MLOOPUV, CD_CALLOC, &(fdata->layers[i].name), 0);
                }
                else if(fdata->layers[i].type == CD_MCOL)
                        CustomData_add_layer(ldata, CD_MLOOPCOL, CD_CALLOC, &(fdata->layers[i].name), 0);
        }               
}
void CustomData_from_bmeshpoly(CustomData *fdata, CustomData *pdata, CustomData *ldata, int total){
        int i;
        for(i=0; i < pdata->totlayer; i++){
                if(pdata->layers[i].type == CD_MTEXPOLY)
                        CustomData_add_layer(fdata, CD_MTFACE, CD_CALLOC, &(pdata->layers[i].name), total);
        }
        for(i=0; i < ldata->totlayer; i++){
                if(ldata->layers[i].type == CD_MLOOPCOL)
                        CustomData_add_layer(fdata, CD_MCOL, CD_CALLOC, &(ldata->layers[i].name), total);
        }
}


void CustomData_bmesh_init_pool(CustomData *data, int allocsize){
        if(data->totlayer)data->pool = BLI_mempool_create(data->totsize, allocsize, allocsize, 0);
}

void CustomData_bmesh_free_block(CustomData *data, void **block)
{
        const LayerTypeInfo *typeInfo;
        int i;

        if(!*block) return;
        for(i = 0; i < data->totlayer; ++i) {
                if(!(data->layers[i].flag & CD_FLAG_NOFREE)) {
                        typeInfo = layerType_getInfo(data->layers[i].type);

                        if(typeInfo->free) {
                                int offset = data->layers[i].offset;
                                typeInfo->free((char*)*block + offset, 1, typeInfo->size);
                        }
                }
        }

        BLI_mempool_free(data->pool, *block);
        *block = NULL;
}

static void CustomData_bmesh_alloc_block(CustomData *data, void **block)
{

        if (*block)
                CustomData_bmesh_free_block(data, block);

        if (data->totsize > 0)
                *block = BLI_mempool_calloc(data->pool);
        else
                *block = NULL;
}

void CustomData_bmesh_copy_data(const CustomData *source, CustomData *dest,
                                                        void *src_block, void **dest_block)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i;

        if (!*dest_block)
                CustomData_bmesh_alloc_block(dest, dest_block);
        
        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type &&
                        strcmp(dest->layers[dest_i].name, source->layers[src_i].name) == 0) {
                        char *src_data = (char*)src_block + source->layers[src_i].offset;
                        char *dest_data = (char*)*dest_block + dest->layers[dest_i].offset;

                        typeInfo = layerType_getInfo(source->layers[src_i].type);

                        if(typeInfo->copy)
                                typeInfo->copy(src_data, dest_data, 1);
                        else
                                memcpy(dest_data, src_data, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }
}

/*Bmesh Custom Data Functions. Should replace editmesh ones with these as well, due to more effecient memory alloc*/
void *CustomData_bmesh_get(const CustomData *data, void *block, int type)
{
        int layer_index;
        
        /* get the layer index of the first layer of type */
        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return (char *)block + data->layers[layer_index].offset;
}

void *CustomData_bmesh_get_n(const CustomData *data, void *block, int type, int n)
{
        int layer_index;
        
        /* get the layer index of the first layer of type */
        layer_index = CustomData_get_layer_index(data, type);
        if(layer_index < 0) return NULL;

        return (char *)block + data->layers[layer_index+n].offset;
}

void CustomData_bmesh_set(const CustomData *data, void *block, int type, void *source)
{
        void *dest = CustomData_bmesh_get(data, block, type);
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        if(!dest) return;

        if(typeInfo->copy)
                typeInfo->copy(source, dest, 1);
        else
                memcpy(dest, source, typeInfo->size);
}

void CustomData_bmesh_set_n(CustomData *data, void *block, int type, int n, void *source)
{
        void *dest = CustomData_bmesh_get_n(data, block, type, n);
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        if(!dest) return;

        if(typeInfo->copy)
                typeInfo->copy(source, dest, 1);
        else
                memcpy(dest, source, typeInfo->size);
}

void CustomData_bmesh_interp(CustomData *data, void **src_blocks, float *weights,
                                                  float *sub_weights, int count, void *dest_block)
{
        int i, j;
        void *source_buf[SOURCE_BUF_SIZE];
        void **sources = source_buf;

        /* slow fallback in case we're interpolating a ridiculous number of
         * elements
         */
        if(count > SOURCE_BUF_SIZE)
                sources = MEM_callocN(sizeof(*sources) * count,
                                                          "CustomData_interp sources");

        /* interpolates a layer at a time */
        for(i = 0; i < data->totlayer; ++i) {
                CustomDataLayer *layer = &data->layers[i];
                const LayerTypeInfo *typeInfo = layerType_getInfo(layer->type);
                if(typeInfo->interp) {
                        for(j = 0; j < count; ++j)
                                sources[j] = (char *)src_blocks[j] + layer->offset;

                        typeInfo->interp(sources, weights, sub_weights, count,
                                                          (char *)dest_block + layer->offset);
                }
        }

        if(count > SOURCE_BUF_SIZE) MEM_freeN(sources);
}

void CustomData_bmesh_set_default(CustomData *data, void **block)
{
        const LayerTypeInfo *typeInfo;
        int i;

        if (!*block)
                CustomData_bmesh_alloc_block(data, block);

        for(i = 0; i < data->totlayer; ++i) {
                int offset = data->layers[i].offset;

                typeInfo = layerType_getInfo(data->layers[i].type);

                if(typeInfo->set_default)
                        typeInfo->set_default((char*)*block + offset, 1);
        }
}

void CustomData_to_bmesh_block(const CustomData *source, CustomData *dest,
                                                        int src_index, void **dest_block)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i, src_offset;

        if (!*dest_block)
                CustomData_bmesh_alloc_block(dest, dest_block);
        
        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        int offset = dest->layers[dest_i].offset;
                        char *src_data = source->layers[src_i].data;
                        char *dest_data = (char*)*dest_block + offset;

                        typeInfo = layerType_getInfo(dest->layers[dest_i].type);
                        src_offset = src_index * typeInfo->size;

                        if(typeInfo->copy)
                                typeInfo->copy(src_data + src_offset, dest_data, 1);
                        else
                                memcpy(dest_data, src_data + src_offset, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }
}

void CustomData_from_bmesh_block(const CustomData *source, CustomData *dest,
                                                          void *src_block, int dest_index)
{
        const LayerTypeInfo *typeInfo;
        int dest_i, src_i, dest_offset;

        /* copies a layer at a time */
        dest_i = 0;
        for(src_i = 0; src_i < source->totlayer; ++src_i) {

                /* find the first dest layer with type >= the source type
                 * (this should work because layers are ordered by type)
                 */
                while(dest_i < dest->totlayer
                          && dest->layers[dest_i].type < source->layers[src_i].type)
                        ++dest_i;

                /* if there are no more dest layers, we're done */
                if(dest_i >= dest->totlayer) return;

                /* if we found a matching layer, copy the data */
                if(dest->layers[dest_i].type == source->layers[src_i].type) {
                        int offset = source->layers[src_i].offset;
                        char *src_data = (char*)src_block + offset;
                        char *dest_data = dest->layers[dest_i].data;

                        typeInfo = layerType_getInfo(dest->layers[dest_i].type);
                        dest_offset = dest_index * typeInfo->size;

                        if(typeInfo->copy)
                                typeInfo->copy(src_data, dest_data + dest_offset, 1);
                        else
                                memcpy(dest_data + dest_offset, src_data, typeInfo->size);

                        /* if there are multiple source & dest layers of the same type,
                         * we don't want to copy all source layers to the same dest, so
                         * increment dest_i
                         */
                        ++dest_i;
                }
        }

}

void CustomData_file_write_info(int type, const char **structname, int *structnum)
{
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        *structname = typeInfo->structname;
        *structnum = typeInfo->structnum;
}

int CustomData_sizeof(int type)
{
        const LayerTypeInfo *typeInfo = layerType_getInfo(type);

        return typeInfo->size;
}

const char *CustomData_layertype_name(int type)
{
        return layerType_getName(type);
}

static int  CustomData_is_property_layer(int type)
{
        if((type == CD_PROP_FLT) || (type == CD_PROP_INT) || (type == CD_PROP_STR))
                return 1;
        return 0;
}

static int cd_layer_find_dupe(CustomData *data, const char *name, int type, int index)
{
        int i;
        /* see if there is a duplicate */
        for(i=0; i<data->totlayer; i++) {
                if(i != index) {
                        CustomDataLayer *layer= &data->layers[i];
                        
                        if(CustomData_is_property_layer(type)) {
                                if(CustomData_is_property_layer(layer->type) && strcmp(layer->name, name)==0) {
                                        return 1;
                                }
                        }
                        else{
                                if(i!=index && layer->type==type && strcmp(layer->name, name)==0) {
                                        return 1;
                                }
                        }
                }
        }
        
        return 0;
}

static int customdata_unique_check(void *arg, const char *name)
{
        struct {CustomData *data; int type; int index;} *data_arg= arg;
        return cd_layer_find_dupe(data_arg->data, name, data_arg->type, data_arg->index);
}

void CustomData_set_layer_unique_name(CustomData *data, int index)
{       
        CustomDataLayer *nlayer= &data->layers[index];
        const LayerTypeInfo *typeInfo= layerType_getInfo(nlayer->type);

        struct {CustomData *data; int type; int index;} data_arg;
        data_arg.data= data;
        data_arg.type= nlayer->type;
        data_arg.index= index;

        if (!typeInfo->defaultname)
                return;
        
        BLI_uniquename_cb(customdata_unique_check, &data_arg, typeInfo->defaultname, '.', nlayer->name, sizeof(nlayer->name));
}

int CustomData_verify_versions(struct CustomData *data, int index)
{
        const LayerTypeInfo *typeInfo;
        CustomDataLayer *layer = &data->layers[index];
        int i, keeplayer = 1;

        if (layer->type >= CD_NUMTYPES) {
                keeplayer = 0; /* unknown layer type from future version */
        }
        else {
                typeInfo = layerType_getInfo(layer->type);

                if (!typeInfo->defaultname && (index > 0) &&
                        data->layers[index-1].type == layer->type)
                        keeplayer = 0; /* multiple layers of which we only support one */
        }

        if (!keeplayer) {
                for (i=index+1; i < data->totlayer; ++i)
                        data->layers[i-1] = data->layers[i];
                data->totlayer--;
        }

        return keeplayer;
}

/****************************** External Files *******************************/

static void customdata_external_filename(char filename[FILE_MAX], ID *id, CustomDataExternal *external)
{
        char *path = (id->lib)? id->lib->filepath: G.main->name;

        BLI_strncpy(filename, external->filename, FILE_MAX);
        BLI_path_abs(filename, path);
}

void CustomData_external_reload(CustomData *data, ID *UNUSED(id), CustomDataMask mask, int totelem)
{
        CustomDataLayer *layer;
        const LayerTypeInfo *typeInfo;
        int i;

        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if(!(mask & (1<<layer->type)));
                else if((layer->flag & CD_FLAG_EXTERNAL) && (layer->flag & CD_FLAG_IN_MEMORY)) {
                        if(typeInfo->free)
                                typeInfo->free(layer->data, totelem, typeInfo->size);
                        layer->flag &= ~CD_FLAG_IN_MEMORY;
                }
        }
}

void CustomData_external_read(CustomData *data, ID *id, CustomDataMask mask, int totelem)
{
        CustomDataExternal *external= data->external;
        CustomDataLayer *layer;
        CDataFile *cdf;
        CDataFileLayer *blay;
        char filename[FILE_MAX];
        const LayerTypeInfo *typeInfo;
        int i, update = 0;

        if(!external)
                return;
        
        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if(!(mask & (1<<layer->type)));
                else if(layer->flag & CD_FLAG_IN_MEMORY);
                else if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->read)
                        update= 1;
        }

        if(!update)
                return;

        customdata_external_filename(filename, id, external);

        cdf= cdf_create(CDF_TYPE_MESH);
        if(!cdf_read_open(cdf, filename)) {
                fprintf(stderr, "Failed to read %s layer from %s.\n", layerType_getName(layer->type), filename);
                return;
        }

        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if(!(mask & (1<<layer->type)));
                else if(layer->flag & CD_FLAG_IN_MEMORY);
                else if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->read) {
                        blay= cdf_layer_find(cdf, layer->type, layer->name);

                        if(blay) {
                                if(cdf_read_layer(cdf, blay)) {
                                        if(typeInfo->read(cdf, layer->data, totelem));
                                        else break;
                                        layer->flag |= CD_FLAG_IN_MEMORY;
                                }
                                else
                                        break;
                        }
                }
        }

        cdf_read_close(cdf);
        cdf_free(cdf);
}

void CustomData_external_write(CustomData *data, ID *id, CustomDataMask mask, int totelem, int free)
{
        CustomDataExternal *external= data->external;
        CustomDataLayer *layer;
        CDataFile *cdf;
        CDataFileLayer *blay;
        const LayerTypeInfo *typeInfo;
        int i, update = 0;
        char filename[FILE_MAX];

        if(!external)
                return;

        /* test if there is anything to write */
        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if(!(mask & (1<<layer->type)));
                else if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->write)
                        update= 1;
        }

        if(!update)
                return;

        /* make sure data is read before we try to write */
        CustomData_external_read(data, id, mask, totelem);
        customdata_external_filename(filename, id, external);

        cdf= cdf_create(CDF_TYPE_MESH);

        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->filesize) {
                        if(layer->flag & CD_FLAG_IN_MEMORY) {
                                cdf_layer_add(cdf, layer->type, layer->name,
                                        typeInfo->filesize(cdf, layer->data, totelem));
                        }
                        else {
                                cdf_free(cdf);
                                return; /* read failed for a layer! */
                        }
                }
        }

        if(!cdf_write_open(cdf, filename)) {
                fprintf(stderr, "Failed to open %s for writing.\n", filename);
                return;
        }

        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->write) {
                        blay= cdf_layer_find(cdf, layer->type, layer->name);

                        if(cdf_write_layer(cdf, blay)) {
                                if(typeInfo->write(cdf, layer->data, totelem));
                                else break;
                        }
                        else
                                break;
                }
        }

        if(i != data->totlayer) {
                fprintf(stderr, "Failed to write data to %s.\n", filename);
                cdf_free(cdf);
                return;
        }

        for(i=0; i<data->totlayer; i++) {
                layer = &data->layers[i];
                typeInfo = layerType_getInfo(layer->type);

                if((layer->flag & CD_FLAG_EXTERNAL) && typeInfo->write) {
                        if(free) {
                                if(typeInfo->free)
                                        typeInfo->free(layer->data, totelem, typeInfo->size);
                                layer->flag &= ~CD_FLAG_IN_MEMORY;
                        }
                }
        }

        cdf_write_close(cdf);
        cdf_free(cdf);
}

void CustomData_external_add(CustomData *data, ID *UNUSED(id), int type, int UNUSED(totelem), const char *filename)
{
        CustomDataExternal *external= data->external;
        CustomDataLayer *layer;
        int layer_index;

        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return;

        layer = &data->layers[layer_index];

        if(layer->flag & CD_FLAG_EXTERNAL)
                return;

        if(!external) {
                external= MEM_callocN(sizeof(CustomDataExternal), "CustomDataExternal");
                data->external= external;
        }
        BLI_strncpy(external->filename, filename, sizeof(external->filename));

        layer->flag |= CD_FLAG_EXTERNAL|CD_FLAG_IN_MEMORY;
}

void CustomData_external_remove(CustomData *data, ID *id, int type, int totelem)
{
        CustomDataExternal *external= data->external;
        CustomDataLayer *layer;
        //char filename[FILE_MAX];
        int layer_index; // i, remove_file;

        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return;

        layer = &data->layers[layer_index];

        if(!external)
                return;

        if(layer->flag & CD_FLAG_EXTERNAL) {
                if(!(layer->flag & CD_FLAG_IN_MEMORY))
                        CustomData_external_read(data, id, (1<<layer->type), totelem);

                layer->flag &= ~CD_FLAG_EXTERNAL;

#if 0
                remove_file= 1;
                for(i=0; i<data->totlayer; i++)
                        if(data->layers[i].flag & CD_FLAG_EXTERNAL)
                                remove_file= 0;

                if(remove_file) {
                        customdata_external_filename(filename, id, external);
                        cdf_remove(filename);
                        CustomData_external_free(data);
                }
#endif
        }
}

int CustomData_external_test(CustomData *data, int type)
{
        CustomDataLayer *layer;
        int layer_index;

        layer_index = CustomData_get_active_layer_index(data, type);
        if(layer_index < 0) return 0;

        layer = &data->layers[layer_index];
        return (layer->flag & CD_FLAG_EXTERNAL);
}

#if 0
void CustomData_external_remove_object(CustomData *data, ID *id)
{
        CustomDataExternal *external= data->external;
        char filename[FILE_MAX];

        if(!external)
                return;

        customdata_external_filename(filename, id, external);
        cdf_remove(filename);
        CustomData_external_free(data);
}
#endif