diff options
Diffstat (limited to 'window.c')
| -rw-r--r-- | window.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/window.c b/window.c new file mode 100644 index 0000000..b7bc5fb --- /dev/null +++ b/window.c @@ -0,0 +1,221 @@ +#include <SDL2/SDL.h> +#include <stdio.h> +#include <stdlib.h> + +typedef struct { + int code_point; + SDL_Point next_glyph_offset; + SDL_Rect bounds; + char *bitmap; + int bitmap_size; +} BDFFontChar; + +typedef struct { + SDL_Rect bounds; + BDFFontChar *chars; + int num_chars; + int char_index_for_code_point[128]; +} BDFFontInfo; + +/* Create a texture containing all of the glyphs in a specified BDF file. */ +SDL_Texture *bdf_create_texture(SDL_Renderer *renderer, BDFFontInfo *font) +{ + SDL_Texture *result; + SDL_Surface *surface = SDL_CreateRGBSurface(0, 8 * font->num_chars, font->bounds.h, 32, 0, 0, 0, 0); + + printf("Made surface of size %dx%d\n", surface->w, surface->h); + SDL_LockSurface(surface); + for (int i = 0; i < font->num_chars; i++) { + BDFFontChar chair = font->chars[i]; + for (int y = 0; y < font->bounds.h; y++) { + int bits_for_row = chair.bitmap[y]; + for (int x = 0; x < 8; x++) { + int bit_index = 7 - x; + int current_bit = bits_for_row & (1 << bit_index); + int xp = x + i * 8; + int yp = y; + ((Uint32*)(surface->pixels))[xp + yp * surface->w] = current_bit ? 0xffffffff : 0; + } + } + } + SDL_UnlockSurface(surface); + + result = SDL_CreateTextureFromSurface(renderer, surface); + if (result == NULL) { + fprintf(stderr, "Failed to create texture: %s\n", SDL_GetError()); + } + SDL_FreeSurface(surface); + return result; +} + +/* + * Loads a BDF font file into a data structure. + * TODO: This is extremely atrocious! + */ +BDFFontInfo bdf_read_font(const char *filename) +{ + FILE *fp; + char *line = NULL; + size_t len = 0; + ssize_t bytes_read; + + BDFFontInfo result; + result.bounds.x = 0; + result.bounds.y = 0; + result.bounds.w = 0; + result.bounds.h = 0; + result.chars = NULL; + result.num_chars = 0; + + fp = fopen(filename, "r"); + if (fp == NULL) { + fprintf(stderr, "Failed to open file from %s\n", filename); + return; + } + + int is_reading_bitmap = 0; + int char_counter = -1; + while ((bytes_read = getline(&line, &len, fp)) != -1) { + if (strncmp(line, "FONTBOUNDINGBOX", 15) == 0) { + sscanf(line, "FONTBOUNDINGBOX %d %d %d %d\n", &result.bounds.w, + &result.bounds.h, + &result.bounds.x, + &result.bounds.y); + + } + + if (strncmp(line, "CHARS", 5) == 0) { + sscanf(line, "CHARS %d\n", &result.num_chars); + result.chars = malloc(result.num_chars * sizeof(BDFFontChar)); + } + + if (strncmp(line, "STARTCHAR", 9) == 0) { + char_counter++; + result.chars[char_counter].code_point = 0; + result.chars[char_counter].next_glyph_offset.x = 0; + result.chars[char_counter].next_glyph_offset.y = 0; + result.chars[char_counter].bounds.x = 0; + result.chars[char_counter].bounds.y = 0; + result.chars[char_counter].bounds.w = 0; + result.chars[char_counter].bounds.h = 0; + result.chars[char_counter].bitmap = NULL; + result.chars[char_counter].bitmap_size = 0; + } + + if (strncmp(line, "ENCODING", 8) == 0) { + int code_point = 0; + sscanf(line, "ENCODING %d\n", &code_point); + if (code_point < 256) + result.char_index_for_code_point[code_point] = char_counter; + result.chars[char_counter].code_point = code_point; + } + + if (strncmp(line, "DWIDTH", 6) == 0) { + sscanf(line, "DWIDTH %d %d\n", &result.chars[char_counter].next_glyph_offset.x, + &result.chars[char_counter].next_glyph_offset.y); + } + + if (strncmp(line, "BBX", 3) == 0) { + sscanf(line, "BBX %d %d %d %d\n", &result.chars[char_counter].bounds.w, + &result.chars[char_counter].bounds.h, + &result.chars[char_counter].bounds.x, + &result.chars[char_counter].bounds.y); + result.chars[char_counter].bounds.x += char_counter * 8; + result.chars[char_counter].bounds.y = -result.chars[char_counter].bounds.y; + } + + if (strncmp(line, "BITMAP", 6) == 0) { + is_reading_bitmap = 1; + } + + if (is_reading_bitmap) { + if (strncmp(line, "ENDCHAR", 7) == 0) { + is_reading_bitmap = 0; + continue; + } + + BDFFontChar *chair = &result.chars[char_counter]; + chair->bitmap = realloc(chair->bitmap, chair->bitmap_size++); + chair->bitmap[chair->bitmap_size - 1] = strtol(line, NULL, 16); + } + } + + fclose(fp); + if (line) { free(line); } + + return result; +} + +BDFFontChar bdf_char_by_code_point(BDFFontInfo *font, int code_point) +{ + for (int i = 0; i < font->num_chars; i++) + if (font->chars[i].code_point == code_point) + return font->chars[i]; +} + +int main(int argc, char **argv) +{ + SDL_Window *window = NULL; + SDL_Renderer *renderer = NULL; + + BDFFontInfo font = bdf_read_font("ter-u12n.bdf"); + printf("Loaded font with %d chars, width %d\n", font.num_chars, font.bounds.w); + + if (SDL_Init(SDL_INIT_VIDEO) != 0) { + fprintf(stderr, "Failed to initalize SDL: %s\n", SDL_GetError()); + return 1; + } + + window = SDL_CreateWindow("Bitmap font test", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, + 640, 480, SDL_WINDOW_SHOWN); + if (window == NULL) { + fprintf(stderr, "Failed to create a window: %s\n", SDL_GetError()); + return 1; + } + + renderer = SDL_CreateRenderer(window, -1, 0); + if (renderer == NULL) { + fprintf(stderr, "Failed to create a renderer: %s\n", SDL_GetError()); + return 1; + } + + SDL_Texture *font_texture = bdf_create_texture(renderer, &font); + SDL_ShowWindow(window); + + const char *testmsg = "Hello, welcome to the bitmap font test!"; + + int is_running = 1; + while (is_running) { + static SDL_Event e; + while (SDL_PollEvent(&e)) { + switch (e.type) { + case SDL_QUIT: + is_running = 0; + break; + } + } + + SDL_RenderClear(renderer); + SDL_Rect dstrect = { 0, 0, 0, 0 }; + for (int i = 0; i < strlen(testmsg); i++) { + const char letter = testmsg[i]; + const int char_index = font.char_index_for_code_point[letter]; + BDFFontChar *glyph = &font.chars[char_index]; + + dstrect.w = glyph->bounds.w; + dstrect.h = glyph->bounds.h; + SDL_RenderCopy(renderer, font_texture, &glyph->bounds, &dstrect); + + dstrect.x += glyph->next_glyph_offset.x; + dstrect.y += glyph->next_glyph_offset.y; + } + SDL_RenderPresent(renderer); + SDL_UpdateWindowSurface(window); + } + + SDL_DestroyRenderer(renderer); + SDL_DestroyWindow(window); + SDL_Quit(); + + return 0; +} |