blf_glyph.c

Go to the documentation of this file.

/*
 * $Id: blf_glyph.c 35453 2011-03-10 13:49:46Z campbellbarton $
 *
 * ***** 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) 2009 Blender Foundation.
 * All rights reserved.
 *
 * 
 * Contributor(s): Blender Foundation
 *
 * ***** END GPL LICENSE BLOCK *****
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>

#include <ft2build.h>

#include FT_FREETYPE_H
#include FT_GLYPH_H
#include FT_OUTLINE_H
#include FT_BITMAP_H

#include "MEM_guardedalloc.h"

#include "DNA_vec_types.h"
#include "DNA_userdef_types.h"

#include "BLI_blenlib.h"

#include "BIF_gl.h"
#include "BLF_api.h"

#include "blf_internal_types.h"
#include "blf_internal.h"


GlyphCacheBLF *blf_glyph_cache_find(FontBLF *font, int size, int dpi)
{
        GlyphCacheBLF *p;

        p= (GlyphCacheBLF *)font->cache.first;
        while (p) {
                if (p->size == size && p->dpi == dpi)
                        return(p);
                p= p->next;
        }
        return(NULL);
}

/* Create a new glyph cache for the current size and dpi. */
GlyphCacheBLF *blf_glyph_cache_new(FontBLF *font)
{
        GlyphCacheBLF *gc;
        int i;

        gc= (GlyphCacheBLF *)MEM_mallocN(sizeof(GlyphCacheBLF), "blf_glyph_cache_new");
        gc->next= NULL;
        gc->prev= NULL;
        gc->size= font->size;
        gc->dpi= font->dpi;

        for (i= 0; i < 257; i++) {
                gc->bucket[i].first= NULL;
                gc->bucket[i].last= NULL;
        }

        gc->textures= (GLuint *)malloc(sizeof(GLuint)*256);
        gc->ntex= 256;
        gc->cur_tex= -1;
        gc->x_offs= 0;
        gc->y_offs= 0;
        gc->pad= 3;

        gc->num_glyphs= font->face->num_glyphs;
        gc->rem_glyphs= font->face->num_glyphs;
        gc->ascender= ((float)font->face->size->metrics.ascender) / 64.0f;
        gc->descender= ((float)font->face->size->metrics.descender) / 64.0f;

        if (FT_IS_SCALABLE(font->face)) {
                gc->max_glyph_width= (float)((font->face->bbox.xMax - font->face->bbox.xMin) *
                                        (((float)font->face->size->metrics.x_ppem) /
                                         ((float)font->face->units_per_EM)));

                gc->max_glyph_height= (float)((font->face->bbox.yMax - font->face->bbox.yMin) *
                                        (((float)font->face->size->metrics.y_ppem) /
                                         ((float)font->face->units_per_EM)));
        }
        else {
                gc->max_glyph_width= ((float)font->face->size->metrics.max_advance) / 64.0f;
                gc->max_glyph_height= ((float)font->face->size->metrics.height) / 64.0f;
        }

        gc->p2_width= 0;
        gc->p2_height= 0;

        BLI_addhead(&font->cache, gc);
        return(gc);
}

void blf_glyph_cache_clear(FontBLF *font)
{
        GlyphCacheBLF *gc;
        GlyphBLF *g;
        int i;

        for(gc=font->cache.first; gc; gc=gc->next) {
                for (i= 0; i < 257; i++) {
                        while (gc->bucket[i].first) {
                                g= gc->bucket[i].first;
                                BLI_remlink(&(gc->bucket[i]), g);
                                blf_glyph_free(g);
                        }
                }
        }

        memset(font->glyph_ascii_table, 0, sizeof(font->glyph_ascii_table));
}

void blf_glyph_cache_free(GlyphCacheBLF *gc)
{
        GlyphBLF *g;
        int i;

        for (i= 0; i < 257; i++) {
                while (gc->bucket[i].first) {
                        g= gc->bucket[i].first;
                        BLI_remlink(&(gc->bucket[i]), g);
                        blf_glyph_free(g);
                }
        }

        if (gc->cur_tex+1 > 0)
                glDeleteTextures(gc->cur_tex+1, gc->textures);
        free((void *)gc->textures);
        MEM_freeN(gc);
}

static void blf_glyph_cache_texture(FontBLF *font, GlyphCacheBLF *gc)
{
        int tot_mem, i;
        unsigned char *buf;

        /* move the index. */
        gc->cur_tex++;

        if (gc->cur_tex >= gc->ntex) {
                gc->ntex *= 2;
                gc->textures= (GLuint *)realloc((void *)gc->textures, sizeof(GLuint)*gc->ntex);
        }

        gc->p2_width= blf_next_p2((gc->rem_glyphs * gc->max_glyph_width) + (gc->pad * 2));
        if (gc->p2_width > font->max_tex_size)
                gc->p2_width= font->max_tex_size;

        i= (int)((gc->p2_width - (gc->pad * 2)) / gc->max_glyph_width);
        gc->p2_height= blf_next_p2(((gc->num_glyphs / i) + 1) * gc->max_glyph_height);

        if (gc->p2_height > font->max_tex_size)
                gc->p2_height= font->max_tex_size;

        tot_mem= gc->p2_width * gc->p2_height;
        buf= (unsigned char *)malloc(tot_mem);
        memset((void *)buf, 0, tot_mem);

        glGenTextures(1, &gc->textures[gc->cur_tex]);
        glBindTexture(GL_TEXTURE_2D, gc->textures[gc->cur_tex]);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

        glTexImage2D(GL_TEXTURE_2D, 0, GL_ALPHA, gc->p2_width, gc->p2_height, 0, GL_ALPHA, GL_UNSIGNED_BYTE, buf);
        free((void *)buf);
}

GlyphBLF *blf_glyph_search(GlyphCacheBLF *gc, unsigned int c)
{
        GlyphBLF *p;
        unsigned int key;

        key= blf_hash(c);
        p= gc->bucket[key].first;
        while (p) {
                if (p->c == c)
                        return(p);
                p= p->next;
        }
        return(NULL);
}

GlyphBLF *blf_glyph_add(FontBLF *font, unsigned int index, unsigned int c)
{
        FT_GlyphSlot slot;
        GlyphBLF *g;
        FT_Error err;
        FT_Bitmap bitmap, tempbitmap;
        int sharp = (U.text_render & USER_TEXT_DISABLE_AA);
        FT_BBox bbox;
        unsigned int key;

        g= blf_glyph_search(font->glyph_cache, c);
        if (g)
                return(g);

        if (sharp)
                err = FT_Load_Glyph(font->face, (FT_UInt)index, FT_LOAD_TARGET_MONO);
        else
                err = FT_Load_Glyph(font->face, (FT_UInt)index, FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING | FT_LOAD_NO_BITMAP); /* Sure about NO_* flags? */
        if (err)
                return(NULL);

        /* get the glyph. */
        slot= font->face->glyph;

        if (sharp) {
                err = FT_Render_Glyph(slot, FT_RENDER_MODE_MONO);

                /* Convert result from 1 bit per pixel to 8 bit per pixel */
                /* Accum errors for later, fine if not interested beyond "ok vs any error" */
                FT_Bitmap_New(&tempbitmap);
                err += FT_Bitmap_Convert(font->ft_lib, &slot->bitmap, &tempbitmap, 1); /* Does Blender use Pitch 1 always? It works so far */
                err += FT_Bitmap_Copy(font->ft_lib, &tempbitmap, &slot->bitmap);
                err += FT_Bitmap_Done(font->ft_lib, &tempbitmap);
        } else {
                err = FT_Render_Glyph(slot, FT_RENDER_MODE_NORMAL);
        }

        if (err || slot->format != FT_GLYPH_FORMAT_BITMAP)
                return(NULL);

        g= (GlyphBLF *)MEM_mallocN(sizeof(GlyphBLF), "blf_glyph_add");
        g->next= NULL;
        g->prev= NULL;
        g->c= c;
        g->idx= (FT_UInt)index;
        g->tex= 0;
        g->build_tex= 0;
        g->bitmap= NULL;
        g->xoff= -1;
        g->yoff= -1;
        g->uv[0][0]= 0.0f;
        g->uv[0][1]= 0.0f;
        g->uv[1][0]= 0.0f;
        g->uv[1][1]= 0.0f;
        bitmap= slot->bitmap;
        g->width= bitmap.width;
        g->height= bitmap.rows;

        if (g->width && g->height) {
                if (sharp) {
                        /* Font buffer uses only 0 or 1 values, Blender expects full 0..255 range */
                        int i;
                        for (i=0; i < (g->width * g->height); i++) {
                                bitmap.buffer[i] = 255 * bitmap.buffer[i];
                        }
                }

                g->bitmap= (unsigned char *)MEM_mallocN(g->width * g->height, "glyph bitmap");
                memcpy((void *)g->bitmap, (void *)bitmap.buffer, g->width * g->height);
        }

        g->advance= ((float)slot->advance.x) / 64.0f;
        g->pos_x= slot->bitmap_left;
        g->pos_y= slot->bitmap_top;
        g->pitch= slot->bitmap.pitch;

        FT_Outline_Get_CBox(&(slot->outline), &bbox);
        g->box.xmin= ((float)bbox.xMin) / 64.0f;
        g->box.xmax= ((float)bbox.xMax) / 64.0f;
        g->box.ymin= ((float)bbox.yMin) / 64.0f;
        g->box.ymax= ((float)bbox.yMax) / 64.0f;

        key= blf_hash(g->c);
        BLI_addhead(&(font->glyph_cache->bucket[key]), g);
        return(g);
}

void blf_glyph_free(GlyphBLF *g)
{
        /* don't need free the texture, the GlyphCache already
         * have a list of all the texture and free it.
         */
        if (g->bitmap)
                MEM_freeN(g->bitmap);
        MEM_freeN(g);
}

static void blf_texture_draw(float uv[2][2], float dx, float y1, float dx1, float y2)
{
        
        glBegin(GL_QUADS);
        glTexCoord2f(uv[0][0], uv[0][1]);
        glVertex2f(dx, y1);
        
        glTexCoord2f(uv[0][0], uv[1][1]);
        glVertex2f(dx, y2);
        
        glTexCoord2f(uv[1][0], uv[1][1]);
        glVertex2f(dx1, y2);
        
        glTexCoord2f(uv[1][0], uv[0][1]);
        glVertex2f(dx1, y1);
        glEnd();
        
}

static void blf_texture5_draw(float uv[2][2], float x1, float y1, float x2, float y2)
{
        float soft[25]= {
                1/60.0f, 1/60.0f, 2/60.0f, 1/60.0f, 1/60.0f, 
                1/60.0f, 3/60.0f, 5/60.0f, 3/60.0f, 1/60.0f, 
                2/60.0f, 5/60.0f, 8/60.0f, 5/60.0f, 2/60.0f, 
                1/60.0f, 3/60.0f, 5/60.0f, 3/60.0f, 1/60.0f, 
                1/60.0f, 1/60.0f, 2/60.0f, 1/60.0f, 1/60.0f};
        
        float color[4], *fp= soft;
        int dx, dy;
        
        glGetFloatv(GL_CURRENT_COLOR, color);
        
        for(dx=-2; dx<3; dx++) {
                for(dy=-2; dy<3; dy++, fp++) {
                        glColor4f(color[0], color[1], color[2], fp[0]*color[3]);
                        blf_texture_draw(uv, x1+dx, y1+dy, x2+dx, y2+dy);
                }
        }
        
        glColor4fv(color);
}

static void blf_texture3_draw(float uv[2][2], float x1, float y1, float x2, float y2)
{
        float soft[9]= {1/16.0f, 2/16.0f, 1/16.0f, 2/16.0f, 4/16.0f, 2/16.0f, 1/16.0f, 2/16.0f, 1/16.0f};
        float color[4], *fp= soft;
        int dx, dy;
        
        glGetFloatv(GL_CURRENT_COLOR, color);
        
        for(dx=-1; dx<2; dx++) {
                for(dy=-1; dy<2; dy++, fp++) {
                        glColor4f(color[0], color[1], color[2], fp[0]*color[3]);
                        blf_texture_draw(uv, x1+dx, y1+dy, x2+dx, y2+dy);
                }
        }
        
        glColor4fv(color);
}

int blf_glyph_render(FontBLF *font, GlyphBLF *g, float x, float y)
{
        GlyphCacheBLF *gc;
        GLint cur_tex;
        float dx, dx1;
        float y1, y2;
        float xo, yo;
        float color[4];

        if ((!g->width) || (!g->height))
                return(1);

        if (g->build_tex == 0) {
                gc= font->glyph_cache;

                if (font->max_tex_size == -1)
                        glGetIntegerv(GL_MAX_TEXTURE_SIZE, (GLint *)&font->max_tex_size);

                if (gc->cur_tex == -1) {
                        blf_glyph_cache_texture(font, gc);
                        gc->x_offs= gc->pad;
                        gc->y_offs= gc->pad;
                }

                if (gc->x_offs > (gc->p2_width - gc->max_glyph_width)) {
                        gc->x_offs= gc->pad;
                        gc->y_offs += gc->max_glyph_height;

                        if (gc->y_offs > (gc->p2_height - gc->max_glyph_height)) {
                                gc->y_offs= gc->pad;
                                blf_glyph_cache_texture(font, gc);
                        }
                }

                g->tex= gc->textures[gc->cur_tex];
                g->xoff= gc->x_offs;
                g->yoff= gc->y_offs;

                glPushClientAttrib(GL_CLIENT_PIXEL_STORE_BIT);
                glPixelStorei(GL_UNPACK_LSB_FIRST, GL_FALSE);
                glPixelStorei(GL_UNPACK_ROW_LENGTH, 0);
                glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

                glBindTexture(GL_TEXTURE_2D, g->tex);
                glTexSubImage2D(GL_TEXTURE_2D, 0, g->xoff, g->yoff, g->width, g->height, GL_ALPHA, GL_UNSIGNED_BYTE, g->bitmap);
                glPopClientAttrib();

                g->uv[0][0]= ((float)g->xoff) / ((float)gc->p2_width);
                g->uv[0][1]= ((float)g->yoff) / ((float)gc->p2_height);
                g->uv[1][0]= ((float)(g->xoff + g->width)) / ((float)gc->p2_width);
                g->uv[1][1]= ((float)(g->yoff + g->height)) / ((float)gc->p2_height);

                /* update the x offset for the next glyph. */
                gc->x_offs += (int)(g->box.xmax - g->box.xmin + gc->pad);

                gc->rem_glyphs--;
                g->build_tex= 1;
        }

        xo= 0.0f;
        yo= 0.0f;

        if (font->flags & BLF_SHADOW) {
                xo= x;
                yo= y;
                x += font->shadow_x;
                y += font->shadow_y;
        }

        dx= floor(x + g->pos_x);
        dx1= dx + g->width;
        y1= y + g->pos_y;
        y2= y + g->pos_y - g->height;

        if (font->flags & BLF_CLIPPING) {
                if (!BLI_in_rctf(&font->clip_rec, dx + font->pos[0], y1 + font->pos[1]))
                        return(0);
                if (!BLI_in_rctf(&font->clip_rec, dx + font->pos[0], y2 + font->pos[1]))
                        return(0);
                if (!BLI_in_rctf(&font->clip_rec, dx1 + font->pos[0], y2 + font->pos[1]))
                        return(0);
                if (!BLI_in_rctf(&font->clip_rec, dx1 + font->pos[0], y1 + font->pos[1]))
                        return(0);
        }

        glGetIntegerv(GL_TEXTURE_2D_BINDING_EXT, &cur_tex);
        if (cur_tex != g->tex)
                glBindTexture(GL_TEXTURE_2D, g->tex);

        if (font->flags & BLF_SHADOW) {
                glGetFloatv(GL_CURRENT_COLOR, color);
                glColor4fv(font->shadow_col);

                if (font->shadow == 3)
                        blf_texture3_draw(g->uv, dx, y1, dx1, y2);
                else if (font->shadow == 5)
                        blf_texture5_draw(g->uv, dx, y1, dx1, y2);
                else
                        blf_texture_draw(g->uv, dx, y1, dx1, y2);

                glColor4fv(color);
                x= xo;
                y= yo;

                dx= floor(x + g->pos_x);
                dx1= dx + g->width;
                y1= y + g->pos_y;
                y2= y + g->pos_y - g->height;
        }

        if (font->blur==3)
                blf_texture3_draw(g->uv, dx, y1, dx1, y2);
        else if (font->blur==5)
                blf_texture5_draw(g->uv, dx, y1, dx1, y2);
        else
                blf_texture_draw(g->uv, dx, y1, dx1, y2);

        return(1);
}