Support no antialiasing.

This commit is contained in:
Adam Harrison 2021-11-22 18:13:43 -05:00
parent 955acf53a3
commit bc5be3c9b7
3 changed files with 38 additions and 26 deletions

View File

@ -6,16 +6,18 @@ static int f_font_load(lua_State *L) {
const char *filename = luaL_checkstring(L, 1);
float size = luaL_checknumber(L, 2);
unsigned int font_hinting = FONT_HINTING_SLIGHT, font_style = 0;
bool subpixel = true;
ERenFontAntialiasing font_antialiasing = FONT_ANTIALIASING_SUBPIXEL;
if (lua_gettop(L) > 2 && lua_istable(L, 3)) {
lua_getfield(L, 3, "antialiasing");
if (lua_isstring(L, -1)) {
const char *antialiasing = lua_tostring(L, -1);
if (antialiasing) {
if (strcmp(antialiasing, "grayscale") == 0) {
subpixel = false;
if (strcmp(antialiasing, "none") == 0) {
font_antialiasing = FONT_ANTIALIASING_NONE;
} else if (strcmp(antialiasing, "grayscale") == 0) {
font_antialiasing = FONT_ANTIALIASING_GRAYSCALE;
} else if (strcmp(antialiasing, "subpixel") == 0) {
subpixel = true;
font_antialiasing = FONT_ANTIALIASING_SUBPIXEL;
} else {
return luaL_error(L, "error in renderer.font.load, unknown antialiasing option: \"%s\"", antialiasing);
}
@ -48,7 +50,7 @@ static int f_font_load(lua_State *L) {
lua_pop(L, 5);
}
RenFont** font = lua_newuserdata(L, sizeof(RenFont*));
*font = ren_font_load(filename, size, subpixel, font_hinting, font_style);
*font = ren_font_load(filename, size, font_antialiasing, font_hinting, font_style);
if (!*font)
return luaL_error(L, "failed to load font");
luaL_setmetatable(L, API_TYPE_FONT);

View File

@ -43,7 +43,7 @@ typedef struct RenFont {
GlyphSet* sets[SUBPIXEL_BITMAPS_CACHED][MAX_LOADABLE_GLYPHSETS];
float size, space_advance, tab_advance;
short max_height;
bool subpixel;
ERenFontAntialiasing antialiasing;
ERenFontHinting hinting;
unsigned char style;
char path[0];
@ -66,16 +66,16 @@ static const char* utf8_to_codepoint(const char *p, unsigned *dst) {
}
static int font_set_load_options(RenFont* font) {
switch (font->hinting) {
case FONT_HINTING_SLIGHT: return FT_LOAD_TARGET_LIGHT | FT_LOAD_FORCE_AUTOHINT;
case FONT_HINTING_FULL: return FT_LOAD_TARGET_NORMAL | FT_LOAD_FORCE_AUTOHINT;
case FONT_HINTING_NONE: return FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING;
}
return FT_LOAD_TARGET_NORMAL | FT_LOAD_NO_HINTING;
int load_target = font->antialiasing == FONT_ANTIALIASING_NONE ? FT_LOAD_TARGET_MONO
: (font->hinting == FONT_HINTING_SLIGHT ? FT_LOAD_TARGET_LIGHT : FT_LOAD_TARGET_NORMAL);
int hinting = font->hinting == FONT_HINTING_NONE ? FT_LOAD_NO_HINTING : FT_LOAD_FORCE_AUTOHINT;
return load_target | hinting;
}
static int font_set_render_options(RenFont* font) {
if (font->subpixel) {
if (font->antialiasing == FONT_ANTIALIASING_NONE)
return FT_RENDER_MODE_MONO;
if (font->antialiasing == FONT_ANTIALIASING_SUBPIXEL) {
unsigned char weights[] = { 0x10, 0x40, 0x70, 0x40, 0x10 } ;
switch (font->hinting) {
case FONT_HINTING_NONE: FT_Library_SetLcdFilter(library, FT_LCD_FILTER_NONE); break;
@ -106,8 +106,8 @@ static int font_set_style(FT_Outline* outline, int x_translation, unsigned char
static void font_load_glyphset(RenFont* font, int idx) {
unsigned int render_option = font_set_render_options(font), load_option = font_set_load_options(font);
int bitmaps_cached = font->subpixel ? SUBPIXEL_BITMAPS_CACHED : 1;
unsigned int byte_width = font->subpixel ? 3 : 1;
int bitmaps_cached = font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? SUBPIXEL_BITMAPS_CACHED : 1;
unsigned int byte_width = font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? 3 : 1;
for (int j = 0, pen_x = 0; j < bitmaps_cached; ++j) {
GlyphSet* set = check_alloc(calloc(1, sizeof(GlyphSet)));
font->sets[j][idx] = set;
@ -117,13 +117,15 @@ static void font_load_glyphset(RenFont* font, int idx) {
continue;
FT_GlyphSlot slot = font->face->glyph;
int glyph_width = slot->bitmap.width / byte_width;
if (font->antialiasing == FONT_ANTIALIASING_NONE)
glyph_width *= 8;
set->metrics[i] = (GlyphMetric){ pen_x, pen_x + glyph_width, 0, slot->bitmap.rows, true, slot->bitmap_left, slot->bitmap_top, (slot->advance.x + slot->lsb_delta - slot->rsb_delta) / 64.0f};
pen_x += glyph_width;
font->max_height = slot->bitmap.rows > font->max_height ? slot->bitmap.rows : font->max_height;
}
if (pen_x == 0)
continue;
set->surface = check_alloc(SDL_CreateRGBSurface(0, pen_x, font->max_height, font->subpixel ? 24 : 8, 0, 0, 0, 0));
set->surface = check_alloc(SDL_CreateRGBSurface(0, pen_x, font->max_height, font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? 24 : 8, 0, 0, 0, 0));
unsigned char* pixels = set->surface->pixels;
for (int i = 0; i < MAX_GLYPHSET; ++i) {
int glyph_index = FT_Get_Char_Index(font->face, i + idx * MAX_GLYPHSET);
@ -136,6 +138,13 @@ static void font_load_glyphset(RenFont* font, int idx) {
for (int line = 0; line < slot->bitmap.rows; ++line) {
int target_offset = set->surface->pitch * line + set->metrics[i].x0 * byte_width;
int source_offset = line * slot->bitmap.pitch;
if (font->antialiasing == FONT_ANTIALIASING_NONE) {
for (int column = 0; column < slot->bitmap.width; ++column) {
int current_source_offset = source_offset + (column / 8);
int source_pixel = slot->bitmap.buffer[current_source_offset];
pixels[++target_offset] = ((source_pixel >> (7 - (column % 8))) & 0x1) << 7;
}
} else
memcpy(&pixels[target_offset], &slot->bitmap.buffer[source_offset], slot->bitmap.width);
}
}
@ -144,9 +153,9 @@ static void font_load_glyphset(RenFont* font, int idx) {
static GlyphSet* font_get_glyphset(RenFont* font, unsigned int codepoint, int subpixel_idx) {
int idx = (codepoint >> 8) % MAX_LOADABLE_GLYPHSETS;
if (!font->sets[font->subpixel ? subpixel_idx : 0][idx])
if (!font->sets[font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? subpixel_idx : 0][idx])
font_load_glyphset(font, idx);
return font->sets[font->subpixel ? subpixel_idx : 0][idx];
return font->sets[font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? subpixel_idx : 0][idx];
}
static RenFont* font_group_get_glyph(GlyphSet** set, GlyphMetric** metric, RenFont** fonts, unsigned int codepoint, int bitmap_index) {
@ -163,7 +172,7 @@ static RenFont* font_group_get_glyph(GlyphSet** set, GlyphMetric** metric, RenFo
return fonts[0];
}
RenFont* ren_font_load(const char* path, float size, bool subpixel, unsigned char hinting, unsigned char style) {
RenFont* ren_font_load(const char* path, float size, ERenFontAntialiasing antialiasing, ERenFontHinting hinting, unsigned char style) {
FT_Face face;
if (FT_New_Face( library, path, 0, &face))
return NULL;
@ -175,7 +184,7 @@ RenFont* ren_font_load(const char* path, float size, bool subpixel, unsigned cha
strcpy(font->path, path);
font->face = face;
font->size = size;
font->subpixel = subpixel;
font->antialiasing = antialiasing;
font->hinting = hinting;
font->style = style;
font->space_advance = (int)font_get_glyphset(font, ' ', 0)->metrics[' '].xadvance;
@ -187,7 +196,7 @@ RenFont* ren_font_load(const char* path, float size, bool subpixel, unsigned cha
}
RenFont* ren_font_copy(RenFont* font, float size) {
return ren_font_load(font->path, size, font->subpixel, font->hinting, font->style);
return ren_font_load(font->path, size, font->antialiasing, font->hinting, font->style);
}
void ren_font_free(RenFont* font) {
@ -206,7 +215,7 @@ void ren_font_free(RenFont* font) {
void ren_font_group_set_tab_size(RenFont **fonts, int n) {
for (int j = 0; j < FONT_FALLBACK_MAX && fonts[j]; ++j) {
for (int i = 0; i < (fonts[j]->subpixel ? SUBPIXEL_BITMAPS_CACHED : 1); ++i)
for (int i = 0; i < (fonts[j]->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? SUBPIXEL_BITMAPS_CACHED : 1); ++i)
font_get_glyphset(fonts[j], '\t', i)->metrics['\t'].xadvance = fonts[j]->space_advance * n;
}
}
@ -274,11 +283,11 @@ float ren_draw_text(RenFont **fonts, const char *text, float x, int y, RenColor
glyph_start += offset;
}
unsigned int* destination_pixel = (unsigned int*)&destination_pixels[surface->pitch * target_y + start_x * bytes_per_pixel];
unsigned char* source_pixel = &source_pixels[line * set->surface->pitch + glyph_start * (font->subpixel ? 3 : 1)];
unsigned char* source_pixel = &source_pixels[line * set->surface->pitch + glyph_start * (font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? 3 : 1)];
for (int x = glyph_start; x < glyph_end; ++x) {
unsigned int destination_color = *destination_pixel;
SDL_Color dst = { (destination_color & surface->format->Rmask) >> surface->format->Rshift, (destination_color & surface->format->Gmask) >> surface->format->Gshift, (destination_color & surface->format->Bmask) >> surface->format->Bshift, (destination_color & surface->format->Amask) >> surface->format->Ashift };
SDL_Color src = { *(font->subpixel ? source_pixel++ : source_pixel), *(font->subpixel ? source_pixel++ : source_pixel), *source_pixel++ };
SDL_Color src = { *(font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? source_pixel++ : source_pixel), *(font->antialiasing == FONT_ANTIALIASING_SUBPIXEL ? source_pixel++ : source_pixel), *source_pixel++ };
r = (color.r * src.r * color.a + dst.r * (65025 - src.r * color.a) + 32767) / 65025;
g = (color.g * src.g * color.a + dst.g * (65025 - src.g * color.a) + 32767) / 65025;
b = (color.b * src.b * color.a + dst.b * (65025 - src.b * color.a) + 32767) / 65025;

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@ -8,11 +8,12 @@
#define FONT_FALLBACK_MAX 4
typedef struct RenFont RenFont;
typedef enum { FONT_HINTING_NONE, FONT_HINTING_SLIGHT, FONT_HINTING_FULL } ERenFontHinting;
typedef enum { FONT_ANTIALIASING_NONE, FONT_ANTIALIASING_GRAYSCALE, FONT_ANTIALIASING_SUBPIXEL } ERenFontAntialiasing;
typedef enum { FONT_STYLE_BOLD = 1, FONT_STYLE_ITALIC = 2, FONT_STYLE_UNDERLINE = 4 } ERenFontStyle;
typedef struct { uint8_t b, g, r, a; } RenColor;
typedef struct { int x, y, width, height; } RenRect;
RenFont* ren_font_load(const char *filename, float size, bool subpixel, unsigned char hinting, unsigned char style);
RenFont* ren_font_load(const char *filename, float size, ERenFontAntialiasing antialiasing, ERenFontHinting hinting, unsigned char style);
RenFont* ren_font_copy(RenFont* font, float size);
void ren_font_free(RenFont *font);
int ren_font_group_get_tab_size(RenFont **font);