src/game/sprite_font.c

   1 #include <SDL.h>
   2 #include "system/stacktrace.h"
   3 #include <stdio.h>
   4 #include <string.h>
   5
   6 #include "math/rect.h"
   7 #include "sdl/renderer.h"
   8 #include "sprite_font.h"
   9 #include "system/lt.h"
  10 #include "system/nth_alloc.h"
  11 #include "system/log.h"
  12
  13 #define FONT_ROW_SIZE 18
  14
  15 struct Sprite_font
  16 {
  17     Lt *lt;
  18     SDL_Texture *texture;
  19 };
  20
  21 Sprite_font *create_sprite_font_from_file(const char *bmp_file_path,
  22                                             SDL_Renderer *renderer)
  23 {
  24     trace_assert(bmp_file_path);
  25     trace_assert(renderer);
  26
  27     Lt *lt = create_lt();
  28
  29     Sprite_font * const sprite_font = PUSH_LT(lt, nth_calloc(1, sizeof(Sprite_font)), free);
  30     if (sprite_font == NULL) {
  31         RETURN_LT(lt, NULL);
  32     }
  33
  34     SDL_Surface * const surface = PUSH_LT(lt, SDL_LoadBMP(bmp_file_path), SDL_FreeSurface);
  35     if (surface == NULL) {
  36         log_fail("Could not load %s: %s\n", bmp_file_path, SDL_GetError());
  37         RETURN_LT(lt, NULL);
  38     }
  39
  40     if (SDL_SetColorKey(surface,
  41                         SDL_TRUE,
  42                         SDL_MapRGB(surface->format,
  43                                    0, 0, 0)) < 0) {
  44         log_fail("SDL_SetColorKey: %s\n", SDL_GetError());
  45         RETURN_LT(lt, NULL);
  46     }
  47
  48     sprite_font->texture = PUSH_LT(
  49         lt,
  50         SDL_CreateTextureFromSurface(renderer, surface),
  51         SDL_DestroyTexture);
  52     if (sprite_font->texture == NULL) {
  53         log_fail("SDL_CreateTextureFromSurface: %s\n", SDL_GetError());
  54         RETURN_LT(lt, NULL);
  55     }
  56
  57     SDL_FreeSurface(RELEASE_LT(lt, surface));
  58
  59     sprite_font->lt = lt;
  60
  61     return sprite_font;
  62 }
  63
  64 void destroy_sprite_font(Sprite_font *sprite_font)
  65 {
  66     trace_assert(sprite_font);
  67     RETURN_LT0(sprite_font->lt);
  68 }
  69
  70 static SDL_Rect sprite_font_char_rect(const Sprite_font *sprite_font, char x)
  71 {
  72     trace_assert(sprite_font);
  73
  74     if (32 <= x && x <= 126) {
  75         const SDL_Rect rect = {
  76             .x = ((x - 32) % FONT_ROW_SIZE) * FONT_CHAR_WIDTH,
  77             .y = ((x - 32) / FONT_ROW_SIZE) * FONT_CHAR_HEIGHT,
  78             .w = FONT_CHAR_WIDTH,
  79             .h = FONT_CHAR_HEIGHT
  80         };
  81         return rect;
  82     } else {
  83         return sprite_font_char_rect(sprite_font, '?');
  84     }
  85 }
  86
  87 int sprite_font_render_text(const Sprite_font *sprite_font,
  88                             SDL_Renderer *renderer,
  89                             Vec position,
  90                             Vec size,
  91                             Color color,
  92                             const char *text)
  93 {
  94     trace_assert(sprite_font);
  95     trace_assert(renderer);
  96     trace_assert(text);
  97
  98     const SDL_Color sdl_color = color_for_sdl(color);
  99
 100     if (SDL_SetTextureColorMod(sprite_font->texture, sdl_color.r, sdl_color.g, sdl_color.b) < 0) {
 101         log_fail("SDL_SetTextureColorMod: %s\n", SDL_GetError());
 102         return -1;
 103     }
 104
 105     if (SDL_SetTextureAlphaMod(sprite_font->texture, sdl_color.a) < 0) {
 106         log_fail("SDL_SetTextureAlphaMod: %s\n", SDL_GetError());
 107         return -1;
 108     }
 109
 110     const size_t text_size = strlen(text);
 111     for (size_t i = 0; i < text_size; ++i) {
 112         const SDL_Rect char_rect = sprite_font_char_rect(sprite_font, text[i]);
 113         const SDL_Rect dest_rect = rect_for_sdl(
 114             rect(
 115                 position.x + (float) FONT_CHAR_WIDTH * (float) i * size.x,
 116                 position.y,
 117                 (float) char_rect.w * size.x,
 118                 (float) char_rect.h * size.y));
 119         if (SDL_RenderCopy(renderer, sprite_font->texture, &char_rect, &dest_rect) < 0) {
 120             return -1;
 121         }
 122     }
 123
 124     return 0;
 125 }
 126
 127 Rect sprite_font_boundary_box(const Sprite_font *sprite_font,
 128                                 Vec position,
 129                                 Vec size,
 130                                 const char *text)
 131 {
 132     trace_assert(sprite_font);
 133     trace_assert(text);
 134     return rect(
 135         position.x, position.y,
 136         size.x * FONT_CHAR_WIDTH * (float) strlen(text),
 137         size.y * FONT_CHAR_HEIGHT);
 138 }