Use font_renderer in aGG font testing program

This commit is contained in:
Francesco Abbate 2020-06-01 16:57:33 +02:00
parent e291e7269a
commit b734390388
5 changed files with 130 additions and 185 deletions

View File

@ -79,6 +79,15 @@ int FontRendererBakeFontBitmap(FontRenderer *fr_, int font_height,
glyph_info.xadvance = x_next - x; glyph_info.xadvance = x_next - x;
x = x_next_i; x = x_next_i;
#ifdef DEBUG_FONT_RENDERER
fprintf(stderr,
"glyph codepoint %3d (ascii: %1c), BOX (%3d, %3d) (%3d, %3d), "
"OFFSET (%.5g, %.5g), X ADVANCE %.5g\n",
codepoint, i,
glyph_info.x0, glyph_info.y0, glyph_info.x1, glyph_info.y1,
glyph_info.xoff, glyph_info.yoff, glyph_info.xadvance);
#endif
} }
return res; return res;
} }

View File

@ -127,6 +127,7 @@ retry:
goto retry; goto retry;
} }
// FIXME: to be removed.
/* adjust glyph's xadvance */ /* adjust glyph's xadvance */
for (int i = 0; i < 256; i++) { for (int i = 0; i < 256; i++) {
set->glyphs[i].xadvance = floor(set->glyphs[i].xadvance); set->glyphs[i].xadvance = floor(set->glyphs[i].xadvance);

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@ -0,0 +1,119 @@
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "SDL_surface.h"
#include "font_renderer.h"
#define MAX_GLYPHSET 256
typedef struct { uint8_t b, g, r, a; } RenColor;
typedef struct { int x, y, width, height; } RenRect;
struct RenImage {
RenColor *pixels;
int width, height;
};
typedef struct RenImage RenImage;
struct GlyphSet {
RenImage *image;
GlyphBitmapInfo glyphs[256];
};
typedef struct GlyphSet GlyphSet;
struct RenFont {
void *data;
GlyphSet *sets[MAX_GLYPHSET];
float size;
int height;
FontRenderer *renderer;
};
typedef struct RenFont RenFont;
static void* check_alloc(void *ptr) {
if (ptr == 0) {
fprintf(stderr, "Fatal error: memory allocation failed\n");
exit(EXIT_FAILURE);
}
return ptr;
}
RenImage* ren_new_image(int width, int height) {
assert(width > 0 && height > 0);
RenImage *image = (RenImage *) malloc(sizeof(RenImage) + width * height * sizeof(RenColor));
check_alloc(image);
image->pixels = (RenColor*) (image + 1);
image->width = width;
image->height = height;
return image;
}
void ren_free_image(RenImage *image) {
free(image);
}
RenFont* ren_load_font_agg(const char *filename, float size) {
RenFont *font = NULL;
/* init font */
font = check_alloc(calloc(1, sizeof(RenFont)));
font->size = size;
font->renderer = FontRendererNew(FONT_RENDERER_HINTING);
// FIXME check for errors
FontRendererLoadFont(font->renderer, filename);
font->height = FontRendererGetFontHeight(font->renderer, size);
fprintf(stderr, "Font height: %d\n", font->height);
return font;
}
static GlyphSet* load_glyphset_agg(RenFont *font, int idx) {
GlyphSet *set = check_alloc(calloc(1, sizeof(GlyphSet)));
/* init image */
int width = 128;
int height = 128;
retry:
set->image = ren_new_image(width, height);
int res = FontRendererBakeFontBitmap(font->renderer, font->height,
(void *) set->image->pixels, width, height,
idx << 8, 256, set->glyphs);
/* retry with a larger image buffer if the buffer wasn't large enough */
if (res < 0) {
width *= 2;
height *= 2;
ren_free_image(set->image);
goto retry;
}
/* convert 8bit data to 32bit */
for (int i = width * height - 1; i >= 0; i--) {
uint8_t n = *((uint8_t*) set->image->pixels + i);
RenColor c = {0xff, 0xff, 0xff, n};
set->image->pixels[i] = c;
}
return set;
}
int main(int argc, char *argv[]) {
if (argc < 3) {
fprintf(stderr, "usage: %s <font-filename> <size>\n", argv[0]);
return 1;
}
const char *filename = argv[1];
const int size = atoi(argv[2]);
RenFont *font = ren_load_font_agg(filename, size);
GlyphSet *set = load_glyphset_agg(font, 0);
SDL_Surface *surface = SDL_CreateRGBSurfaceWithFormatFrom(
set->image->pixels,
set->image->width, set->image->height, 32, set->image->width * 4,
SDL_PIXELFORMAT_RGBA32);
SDL_SaveBMP(surface, "agg-glyphset.bmp");
return 0;
}

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@ -1,184 +0,0 @@
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include "SDL_surface.h"
#include "font_renderer_alpha.h"
#define MAX_GLYPHSET 256
typedef struct { uint8_t b, g, r, a; } RenColor;
typedef struct { int x, y, width, height; } RenRect;
// Mirrors stbtt_bakedchar.
struct GlyphBitmapInfo {
unsigned short x0, y0, x1, y1;
float xoff, yoff, xadvance;
};
struct RenImage {
RenColor *pixels;
int width, height;
};
struct GlyphSetA {
RenImage *image;
GlyphBitmapInfo glyphs[256];
};
struct RenFontA {
font_renderer_alpha *renderer;
float size;
int height;
float ascender, descender;
// For some reason the font's height used in renderer.c
// when calling BakeFontBitmap is 0.5 off from 'height'.
float height_bitmap;
};
template <typename T>
static T* check_alloc(T *ptr) {
if (ptr == 0) {
fprintf(stderr, "Fatal error: memory allocation failed\n");
exit(EXIT_FAILURE);
}
return ptr;
}
RenImage* ren_new_image(int width, int height) {
assert(width > 0 && height > 0);
RenImage *image = (RenImage *) malloc(sizeof(RenImage) + width * height * sizeof(RenColor));
check_alloc(image);
image->pixels = (RenColor*) (image + 1);
image->width = width;
image->height = height;
return image;
}
void ren_free_image(RenImage *image) {
free(image);
}
RenFontA* ren_load_font_agg(const char *filename, float size) {
RenFontA *font = NULL;
/* init font */
font = (RenFontA *) check_alloc(calloc(1, sizeof(RenFontA)));
font->size = size;
font->renderer = new font_renderer_alpha(false, false);
font->renderer->load_font(filename);
double ascender, descender;
font->renderer->get_font_vmetrics(ascender, descender);
int face_height = font->renderer->get_face_height();
// Gives the font's ascender and descender like stbtt.
fprintf(stderr, "Font metrics ascender: %g descender: %g\n", ascender * face_height, descender * face_height);
float scale = font->renderer->scale_for_em_to_pixels(size);
font->height = (ascender - descender) * face_height * scale + 0.5;
font->height_bitmap = (ascender - descender) * face_height * scale;
font->descender = descender * font->height_bitmap;
font->ascender = ascender * font->height_bitmap;
fprintf(stderr, "Font's pixel ascender: %g descender: %g sum: %g\n", font->ascender, font->descender, font->ascender - font->descender);
fprintf(stderr, "Font height: %d\n", font->height);
return font;
}
static GlyphSetA* load_glyphset_agg(RenFontA *font, int idx) {
const int pixel_size = 1;
GlyphSetA *set = (GlyphSetA *) check_alloc(calloc(1, sizeof(GlyphSetA)));
/* init image */
int width = 128;
int height = 128;
retry:
set->image = ren_new_image(width, height);
memset(set->image->pixels, 0x00, width * height * pixel_size);
// NOTE here that render.c with stb_truetype is really using font->height_bitmap.
fprintf(stderr, "Using height: %d in BakeFontBitmap\n", font->height);
const int pad_y = font->height * 2 / 10;
const int ascender_px = int(font->ascender + 0.5), descender_px = int(font->descender + 0.5);
const int y_step = font->height + 2 * pad_y;
agg::rendering_buffer ren_buf((agg::int8u *) set->image->pixels, width, height, -width * pixel_size);
int x = 0, y = height;
int res = 0;
const agg::alpha8 text_color(0xff);
for (int i = 0; i < 256; i++) {
int codepoint = (idx << 8) | i;
if (x + font->height > width) {
x = 0;
y -= y_step;
}
if (y - font->height - 2 * pad_y < 0) {
res = -1;
break;
}
const int y_baseline = y - pad_y - font->height;
// FIXME: using font->height_bitmap below seems logically correct but
// the font size is bigger than what printed by BakeFontBitmap.
double x_next = x, y_next = y_baseline;
font->renderer->render_codepoint(ren_buf, font->height, text_color, x_next, y_next, codepoint);
int x_next_i = int(x_next + 0.5);
GlyphBitmapInfo& glyph_info = set->glyphs[i];
glyph_info.x0 = x;
glyph_info.y0 = height - (y_baseline + ascender_px + pad_y);
glyph_info.x1 = x_next_i;
glyph_info.y1 = height - (y_baseline + descender_px - pad_y);
glyph_info.xoff = 0;
glyph_info.yoff = -font->ascender;
glyph_info.xadvance = x_next - x;
fprintf(stderr,
"glyph codepoint %3d (ascii: %1c), BOX (%3d, %3d) (%3d, %3d), "
"OFFSET (%.5g, %.5g), X ADVANCE %.5g\n",
codepoint, i,
glyph_info.x0, glyph_info.y0, glyph_info.x1, glyph_info.y1,
glyph_info.xoff, glyph_info.yoff, glyph_info.xadvance);
x = x_next_i;
}
/* retry with a larger image buffer if the buffer wasn't large enough */
if (res < 0) {
width *= 2;
height *= 2;
ren_free_image(set->image);
goto retry;
}
/* convert 8bit data to 32bit */
for (int i = width * height - 1; i >= 0; i--) {
uint8_t n = *((uint8_t*) set->image->pixels + i);
RenColor c = {0xff, 0xff, 0xff, n};
set->image->pixels[i] = c;
}
return set;
}
extern "C" int main(int argc, char *argv[]);
int main(int argc, char *argv[]) {
if (argc < 3) {
fprintf(stderr, "usage: %s <font-filename> <size>\n", argv[0]);
return 1;
}
const char *filename = argv[1];
const int size = atoi(argv[2]);
RenFontA *font = ren_load_font_agg(filename, size);
GlyphSetA *set = load_glyphset_agg(font, 0);
SDL_Surface *surface = SDL_CreateRGBSurfaceWithFormatFrom(
set->image->pixels,
set->image->width, set->image->height, 32, set->image->width * 4,
SDL_PIXELFORMAT_RGBA32);
SDL_SaveBMP(surface, "agg-glyphset.bmp");
return 0;
}

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@ -6,7 +6,7 @@ executable('stb-font-render-test',
) )
executable('agg-font-render-test', executable('agg-font-render-test',
['agg_font_render_test.cpp', '../src/agg_font_freetype.cpp'], ['../src/agg_font_freetype.cpp', '../src/font_renderer.cpp', 'agg_font_render_test.c'],
include_directories: lite_include, include_directories: lite_include,
dependencies: [sdl_dep, libagg_dep, freetype_dep, libm, libdl], dependencies: [sdl_dep, libagg_dep, freetype_dep, libm, libdl],
install: false, install: false,