Make the FontRenderer's Bitmap struct opaque outside the library

This commit is contained in:
Francesco Abbate 2020-06-11 17:52:00 +02:00
parent ce664f85b1
commit 117714390a
3 changed files with 37 additions and 30 deletions

View File

@ -7,8 +7,29 @@
#include "font_renderer_alpha.h" #include "font_renderer_alpha.h"
// Important: when a subpixel scale is used the width below will be the width in logical pixel.
// As each logical pixel contains 3 subpixels it means that the 'pixels' pointer
// will hold enough space for '3 * width' uint8_t values.
struct FontRendererBitmap {
agg::int8u *pixels;
int width, height;
};
typedef agg::blender_rgb_gamma<agg::rgba8, agg::order_bgra, agg::gamma_lut<> > blender_gamma_type; typedef agg::blender_rgb_gamma<agg::rgba8, agg::order_bgra, agg::gamma_lut<> > blender_gamma_type;
FontRendererBitmap* FontRendererBitmapNew(int width, int height, int subpixel_scale) {
FontRendererBitmap *image = (FontRendererBitmap *) malloc(sizeof(FontRendererBitmap) + width * height * subpixel_scale);
if (!image) { return NULL; }
image->pixels = (agg::int8u *) (image + 1);
image->width = width;
image->height = height;
return image;
}
void FontRendererBitmapFree(FontRendererBitmap *image) {
free(image);
}
class FontRendererImpl { class FontRendererImpl {
public: public:
// Conventional LUT values: (1./3., 2./9., 1./9.) // Conventional LUT values: (1./3., 2./9., 1./9.)
@ -149,11 +170,14 @@ static int ceil_to_multiple(int n, int p) {
} }
int FontRendererBakeFontBitmap(FontRenderer *font_renderer, int font_height, int FontRendererBakeFontBitmap(FontRenderer *font_renderer, int font_height,
void *pixels, int pixels_width, int pixels_height, FontRendererBitmap *image,
int first_char, int num_chars, GlyphBitmapInfo *glyphs, int subpixel_scale) int first_char, int num_chars, GlyphBitmapInfo *glyphs, int subpixel_scale)
{ {
font_renderer_alpha& renderer_alpha = font_renderer->renderer_alpha(); font_renderer_alpha& renderer_alpha = font_renderer->renderer_alpha();
agg::int8u *pixels = image->pixels;
const int pixels_width = image->width, pixels_height = image->height;
const int pixel_size = 1; const int pixel_size = 1;
memset(pixels, 0x00, pixels_width * pixels_height * subpixel_scale * pixel_size); memset(pixels, 0x00, pixels_width * pixels_height * subpixel_scale * pixel_size);
@ -167,7 +191,7 @@ int FontRendererBakeFontBitmap(FontRenderer *font_renderer, int font_height,
const int y_step = font_height + 2 * pad_y; const int y_step = font_height + 2 * pad_y;
agg::lcd_distribution_lut& lcd_lut = font_renderer->lcd_distribution_lut(); agg::lcd_distribution_lut& lcd_lut = font_renderer->lcd_distribution_lut();
agg::rendering_buffer ren_buf((agg::int8u *) pixels, pixels_width * subpixel_scale, pixels_height, -pixels_width * subpixel_scale * pixel_size); agg::rendering_buffer ren_buf(pixels, pixels_width * subpixel_scale, pixels_height, -pixels_width * subpixel_scale * pixel_size);
// When using subpixel font rendering it is needed to leave a padding pixel on the left and on the right. // When using subpixel font rendering it is needed to leave a padding pixel on the left and on the right.
// Since each pixel is composed by n subpixel we set below x_start to subpixel_scale instead than zero. // Since each pixel is composed by n subpixel we set below x_start to subpixel_scale instead than zero.
const int x_start = subpixel_scale; const int x_start = subpixel_scale;

View File

@ -12,13 +12,7 @@ typedef struct {
float xoff, yoff, xadvance; float xoff, yoff, xadvance;
} GlyphBitmapInfo; } GlyphBitmapInfo;
// Important: when a subpixel scale is used the width below will be the width in logical pixel. typedef struct FontRendererBitmap FontRendererBitmap;
// As each logical pixel contains 3 subpixels it means that the 'pixels' pointer
// will hold enough space for '3 * width' uint8_t values.
typedef struct {
uint8_t *pixels;
int width, height;
} FontRendererBitmap;
struct FontRendererImpl; struct FontRendererImpl;
typedef struct FontRendererImpl FontRenderer; typedef struct FontRendererImpl FontRenderer;
@ -46,7 +40,7 @@ int FontRendererLoadFont(FontRenderer *, const char *filename);
int FontRendererGetFontHeight(FontRenderer *, float size); int FontRendererGetFontHeight(FontRenderer *, float size);
int FontRendererBakeFontBitmap(FontRenderer *, int font_height, int FontRendererBakeFontBitmap(FontRenderer *, int font_height,
void *pixels, int pixels_width, int pixels_height, FontRendererBitmap *image,
int first_char, int num_chars, GlyphBitmapInfo *glyph_info, int first_char, int num_chars, GlyphBitmapInfo *glyph_info,
int subpixel_scale); int subpixel_scale);
@ -65,6 +59,10 @@ void FontRendererBlendGammaSubpixel(FontRenderer *font_renderer,
const FontRendererBitmap *glyphs_bitmap, const FontRendererBitmap *glyphs_bitmap,
const GlyphBitmapInfo *glyph, FontRendererColor color); const GlyphBitmapInfo *glyph, FontRendererColor color);
FontRendererBitmap* FontRendererBitmapNew(int width, int height, int subpixel_scale);
void FontRendererBitmapFree(FontRendererBitmap *image);
#ifdef __cplusplus #ifdef __cplusplus
} }
#endif #endif

View File

@ -104,21 +104,6 @@ void ren_free_image(RenImage *image) {
free(image); free(image);
} }
// FIXME: move this function into FontRenderer and change name.
FontRendererBitmap* ren_new_coverage_image(int width, int height, int subpixel_scale) {
assert(width > 0 && height > 0);
FontRendererBitmap *image = malloc(sizeof(FontRendererBitmap) + width * height * subpixel_scale * sizeof(uint8_t));
check_alloc(image);
image->pixels = (void*) (image + 1);
image->width = width;
image->height = height;
return image;
}
void ren_free_coverage_image(FontRendererBitmap *image) {
free(image);
}
static GlyphSet* load_glyphset(RenFont *font, int idx) { static GlyphSet* load_glyphset(RenFont *font, int idx) {
GlyphSet *set = check_alloc(calloc(1, sizeof(GlyphSet))); GlyphSet *set = check_alloc(calloc(1, sizeof(GlyphSet)));
@ -128,17 +113,17 @@ static GlyphSet* load_glyphset(RenFont *font, int idx) {
int width = 128; int width = 128;
int height = 128; int height = 128;
retry: retry:
set->image = ren_new_coverage_image(width, height, subpixel_scale); set->image = FontRendererBitmapNew(width, height, subpixel_scale);
check_alloc(set->image);
int res = FontRendererBakeFontBitmap(font->renderer, font->height, int res = FontRendererBakeFontBitmap(font->renderer, font->height,
(void *) set->image->pixels, width, height, set->image, idx << 8, 256, set->glyphs, subpixel_scale);
idx << 8, 256, set->glyphs, subpixel_scale);
/* retry with a larger image buffer if the buffer wasn't large enough */ /* retry with a larger image buffer if the buffer wasn't large enough */
if (res < 0) { if (res < 0) {
width *= 2; width *= 2;
height *= 2; height *= 2;
ren_free_coverage_image(set->image); FontRendererBitmapFree(set->image);
goto retry; goto retry;
} }
@ -188,7 +173,7 @@ void ren_free_font(RenFont *font) {
for (int i = 0; i < MAX_GLYPHSET; i++) { for (int i = 0; i < MAX_GLYPHSET; i++) {
GlyphSet *set = font->sets[i]; GlyphSet *set = font->sets[i];
if (set) { if (set) {
ren_free_coverage_image(set->image); FontRendererBitmapFree(set->image);
free(set); free(set);
} }
} }