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 region positions. */ 65 66 position_t *pos; 67 68 } stored_regions_t; 69 70 71 72 /* A simple sprite abstraction. */ 73 74 typedef struct 75 { 76 /* The sprite image. */ 77 78 image_t *image; 79 80 /* The stored regions to be used to unplot the sprite. */ 81 82 stored_regions_t *regions; 83 84 /* The vertical scaling factor translating display rows to image 85 coordinates. */ 86 87 int yscale; 88 89 } sprite_t; 90 91 92 93 /* Initialise stored regions, allocating memory and a structure to access it. 94 95 Stored_Regions(<name>, int, int) 96 */ 97 98 #define Stored_Regions(NAME, FRAMES, SIZE) \ 99 uint8_t __##NAME##_image[(FRAMES) * (SIZE)]; \ 100 position_t __##NAME##_pos[FRAMES]; \ 101 stored_regions_t NAME = { \ 102 .image=__##NAME##_image, \ 103 .size=SIZE, \ 104 .stored=0, \ 105 .pos=__##NAME##_pos}; 106 107 /* Access functions. */ 108 109 position_t *image_get_stored_position(stored_regions_t *r, int frame); 110 111 uint8_t *image_get_stored_region(stored_regions_t *r, int frame); 112 113 114 115 /* Initialise a sprite object using an existing image, creating stored regions 116 for the animation of the sprite. 117 118 Sprite(<name>, image_t *, int, int) 119 */ 120 121 #define Sprite(NAME, IMAGE, FRAMES, YSCALE) \ 122 Stored_Regions(__##NAME##_regions, FRAMES, \ 123 (IMAGE)->width * (IMAGE)->height * (YSCALE)); \ 124 sprite_t NAME = { \ 125 .image=IMAGE, \ 126 .regions=&(__##NAME##_regions), \ 127 .yscale=YSCALE}; 128 129 #endif /* __IMAGE_H__ */