lite-xl/tests/agg_font_render_test.c

123 lines
3.0 KiB
C

#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, 1.8);
if (FontRendererLoadFont(font->renderer, filename)) {
free(font);
return NULL;
}
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);
const int subpixel_scale = 3;
int res = FontRendererBakeFontBitmap(font->renderer, font->height,
(void *) set->image->pixels, width, height,
idx << 8, 256, set->glyphs, subpixel_scale);
/* 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;
}