src/game/sprite_font.c

   1 #include <SDL2/SDL.h>
   2 #include <assert.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/error.h"
  10 #include "system/lt.h"
  11 #include "system/nth_alloc.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     assert(bmp_file_path);
  25     assert(renderer);
  26
  27     Lt * const lt = create_lt();
  28     if (lt == NULL) {
  29         return NULL;
  30     }
  31
  32     Sprite_font * const sprite_font = PUSH_LT(lt, nth_alloc(sizeof(Sprite_font)), free);
  33     if (sprite_font == NULL) {
  34         throw_error(ERROR_TYPE_LIBC);
  35         RETURN_LT(lt, NULL);
  36     }
  37
  38     SDL_Surface * const surface = PUSH_LT(lt, SDL_LoadBMP(bmp_file_path), SDL_FreeSurface);
  39     if (surface == NULL) {
  40         throw_error(ERROR_TYPE_SDL2);
  41         RETURN_LT(lt, NULL);
  42     }
  43
  44     if (SDL_SetColorKey(surface,
  45                         SDL_TRUE,
  46                         SDL_MapRGB(surface->format,
  47                                    0, 0, 0)) < 0) {
  48         throw_error(ERROR_TYPE_SDL2);
  49         RETURN_LT(lt, NULL);
  50     }
  51
  52     sprite_font->texture = PUSH_LT(
  53         lt,
  54         SDL_CreateTextureFromSurface(renderer, surface),
  55         SDL_DestroyTexture);
  56     if (sprite_font->texture == NULL) {
  57         throw_error(ERROR_TYPE_SDL2);
  58         RETURN_LT(lt, NULL);
  59     }
  60
  61     SDL_FreeSurface(RELEASE_LT(lt, surface));
  62
  63     sprite_font->lt = lt;
  64
  65     return sprite_font;
  66 }
  67
  68 void destroy_sprite_font(Sprite_font *sprite_font)
  69 {
  70     assert(sprite_font);
  71     RETURN_LT0(sprite_font->lt);
  72 }
  73
  74 static SDL_Rect sprite_font_char_rect(const Sprite_font *sprite_font, char x)
  75 {
  76     assert(sprite_font);
  77
  78     if (32 <= x && x <= 126) {
  79         const SDL_Rect rect = {
  80             .x = ((x - 32) % FONT_ROW_SIZE) * FONT_CHAR_WIDTH,
  81             .y = ((x - 32) / FONT_ROW_SIZE) * FONT_CHAR_HEIGHT,
  82             .w = FONT_CHAR_WIDTH,
  83             .h = FONT_CHAR_HEIGHT
  84         };
  85         return rect;
  86     } else {
  87         return sprite_font_char_rect(sprite_font, '?');
  88     }
  89 }
  90
  91 int sprite_font_render_text(const Sprite_font *sprite_font,
  92                             SDL_Renderer *renderer,
  93                             Vec position,
  94                             Vec size,
  95                             Color color,
  96                             const char *text)
  97 {
  98     assert(sprite_font);
  99     assert(renderer);
 100     assert(text);
 101
 102     const SDL_Color sdl_color = color_for_sdl(color);
 103
 104     if (SDL_SetTextureColorMod(sprite_font->texture, sdl_color.r, sdl_color.g, sdl_color.b) < 0) {
 105         throw_error(ERROR_TYPE_SDL2);
 106         return -1;
 107     }
 108
 109     if (SDL_SetTextureAlphaMod(sprite_font->texture, sdl_color.a) < 0) {
 110         throw_error(ERROR_TYPE_SDL2);
 111         return -1;
 112     }
 113
 114     const size_t text_size = strlen(text);
 115     for (size_t i = 0; i < text_size; ++i) {
 116         const SDL_Rect char_rect = sprite_font_char_rect(sprite_font, text[i]);
 117         const SDL_Rect dest_rect = rect_for_sdl(
 118             rect(
 119                 position.x + (float) FONT_CHAR_WIDTH * (float) i * size.x,
 120                 position.y,
 121                 (float) char_rect.w * size.x,
 122                 (float) char_rect.h * size.y));
 123         if (SDL_RenderCopy(renderer, sprite_font->texture, &char_rect, &dest_rect) < 0) {
 124             return -1;
 125         }
 126     }
 127
 128     return 0;
 129 }
 130
 131 Rect sprite_font_boundary_box(const Sprite_font *sprite_font,
 132                                 Vec position,
 133                                 Vec size,
 134                                 const char *text)
 135 {
 136     assert(sprite_font);
 137     assert(text);
 138     return rect(
 139         position.x, position.y,
 140         size.x * FONT_CHAR_WIDTH * (float) strlen(text),
 141         size.y * FONT_CHAR_HEIGHT);
 142 }