1 /* 2 * Common image-related functions. 3 * 4 * Copyright (C) 2018 Paul Boddie <paul@boddie.org.uk> 5 * 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation, either version 3 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program. If not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #ifndef __IMAGE_H__ 21 #define __IMAGE_H__ 22 23 #include <stdint.h> 24 25 26 27 /* Image data type. */ 28 29 typedef struct 30 { 31 /* Image width and height. */ 32 33 uint32_t width, height; 34 35 /* Image data. */ 36 37 uint8_t image[]; 38 39 } image_t; 40 41 42 43 /* Stored display regions. */ 44 45 typedef struct 46 { 47 /* Position of the stored region on the screen. */ 48 49 int x, y; 50 51 } position_t; 52 53 typedef struct 54 { 55 /* Stored region overplotted by the sprite. */ 56 57 uint8_t *image; 58 uint32_t size; 59 60 /* Number of stored frames. */ 61 62 int stored; 63 64 } stored_regions_t; 65 66 67 68 /* A simple sprite abstraction. */ 69 70 typedef struct 71 { 72 /* The sprite image. */ 73 74 image_t *image; 75 76 /* The stored regions to be used to unplot the sprite. */ 77 78 stored_regions_t *regions; 79 80 /* Sprite frame positions. */ 81 82 position_t *pos; 83 84 /* Colour key for transparency. */ 85 86 int key; 87 88 /* The vertical scaling factor translating display rows to image 89 coordinates. */ 90 91 int yscale; 92 93 /* The display associated with the sprite. */ 94 95 display_config_t *cfg; 96 97 } sprite_t; 98 99 100 101 /* Initialise stored regions, allocating memory and a structure to access it. 102 103 Stored_Regions(<name>, int frames, int size) 104 */ 105 106 #define Stored_Regions(NAME, FRAMES, SIZE) \ 107 uint8_t __##NAME##_image[(FRAMES) * (SIZE)]; \ 108 stored_regions_t NAME = { \ 109 .image = __##NAME##_image, \ 110 .size = SIZE, \ 111 .stored = 0}; 112 113 /* Access functions. */ 114 115 position_t *image_get_stored_position(sprite_t *s, int frame); 116 117 uint8_t *image_get_stored_region(stored_regions_t *r, int frame); 118 119 120 121 /* Initialise a sprite object using an existing image without the capability of 122 storing regions of the screen. 123 124 SpriteOverwriting(<name>, image_t *image, display_config_t *cfg, int frames, 125 int key, int yscale) 126 */ 127 128 #define SpriteOverwriting(NAME, IMAGE, CFG, FRAMES, KEY, YSCALE) \ 129 position_t __##NAME##_pos[FRAMES]; \ 130 \ 131 sprite_t NAME = { \ 132 .image = IMAGE, \ 133 .regions = 0, \ 134 .key = KEY, \ 135 .yscale = YSCALE, \ 136 .cfg = CFG, \ 137 .pos = __##NAME##_pos}; 138 139 /* Initialise a sprite object using an existing image, creating stored regions 140 for the animation of the sprite. 141 142 Sprite(<name>, image_t *image, display_config_t *cfg, int frames, int key, 143 int yscale) 144 */ 145 146 #define Sprite(NAME, IMAGE, CFG, FRAMES, KEY, YSCALE) \ 147 Stored_Regions(__##NAME##_regions, FRAMES, \ 148 (IMAGE)->width * (IMAGE)->height * (YSCALE)); \ 149 position_t __##NAME##_pos[FRAMES]; \ 150 \ 151 sprite_t NAME = { \ 152 .image = IMAGE, \ 153 .regions = &(__##NAME##_regions), \ 154 .key = KEY, \ 155 .yscale = YSCALE, \ 156 .cfg = CFG, \ 157 .pos = __##NAME##_pos}; 158 159 /* Sprite plotting operations. */ 160 161 void image_plot_sprite(sprite_t *s); 162 163 void image_unplot_sprite(sprite_t *s); 164 165 void image_unplot_sprite_from_image(sprite_t *s, sprite_t *bg, 166 int xorigin, int yorigin); 167 168 /* Update operations. */ 169 170 position_t *image_get_sprite_position(sprite_t *s); 171 172 void image_set_sprite_position(sprite_t *s, int x, int y); 173 174 /* Convenience operations. */ 175 176 void image_plot_sprite_section(sprite_t *s, 177 int xstart, int ystart, int xsize, int ysize, 178 int x, int y, int key); 179 180 void image_tile_sprite(sprite_t *s, int xsource, int ysource, 181 int width, int height, 182 int xdisplay, int ydisplay); 183 184 void image_update_scrolled_tiled_image(sprite_t *s, int xorigin, int yorigin, 185 int xstep, int ystep); 186 187 void image_update_tiled_image(sprite_t *s, int xorigin, int yorigin, 188 int width, int height, 189 int xdisplay, int ydisplay); 190 191 #endif /* __IMAGE_H__ */