diff options
| -rw-r--r-- | texture.c | 124 | ||||
| -rw-r--r-- | texture.h | 27 |
2 files changed, 151 insertions, 0 deletions
diff --git a/texture.c b/texture.c new file mode 100644 index 0000000..3145344 --- /dev/null +++ b/texture.c @@ -0,0 +1,124 @@ +#include "texture.h" + +void imv_init_texture(struct imv_texture *tex, SDL_Renderer *r) +{ + tex->renderer = r; + tex->num_chunks = 0; + tex->chunks = NULL; + + SDL_RendererInfo ri; + SDL_GetRendererInfo(r, &ri); + tex->chunk_width = ri.max_texture_width; + tex->chunk_height = ri.max_texture_height; +} + +void imv_destroy_texture(struct imv_texture *tex) +{ + if(tex->num_chunks > 0) { + for(int i = 0; i < tex->num_chunks; ++i) { + SDL_DestroyTexture(tex->chunks[i]); + } + free(tex->chunks); + tex->num_chunks = 0; + tex->chunks = NULL; + tex->renderer = NULL; + } +} + +int imv_texture_set_image(struct imv_texture *tex, FIBITMAP *image) +{ + FIBITMAP *frame = FreeImage_ConvertTo32Bits(image); + tex->width = FreeImage_GetWidth(frame); + tex->height = FreeImage_GetHeight(frame); + + char* pixels = (char*)FreeImage_GetBits(frame); + + //figure out how many chunks are needed, and create them + if(tex->num_chunks > 0) { + for(int i = 0; i < tex->num_chunks; ++i) { + SDL_DestroyTexture(tex->chunks[i]); + } + free(tex->chunks); + } + + tex->num_chunks_wide = 1 + tex->width / tex->chunk_width; + tex->num_chunks_tall = 1 + tex->height / tex->chunk_height; + + tex->last_chunk_width = tex->width % tex->chunk_width; + tex->last_chunk_height = tex->height % tex->chunk_height; + + if(tex->last_chunk_width == 0) { + tex->last_chunk_width = tex->chunk_width; + } + if(tex->last_chunk_height == 0) { + tex->last_chunk_height = tex->chunk_height; + } + + tex->num_chunks = tex->num_chunks_wide * tex->num_chunks_tall; + tex->chunks = (SDL_Texture**)malloc(sizeof(SDL_Texture*) * tex->num_chunks); + + int failed_at = -1; + for(int y = 0; y < tex->num_chunks_tall; ++y) { + for(int x = 0; x < tex->num_chunks_wide; ++x) { + const int is_last_h_chunk = (x == tex->num_chunks_wide - 1); + const int is_last_v_chunk = (y == tex->num_chunks_tall - 1); + tex->chunks[x + y * tex->num_chunks_wide] = + SDL_CreateTexture(tex->renderer, + SDL_PIXELFORMAT_RGB888, + SDL_TEXTUREACCESS_STATIC, + is_last_h_chunk ? tex->last_chunk_width : tex->chunk_width, + is_last_v_chunk ? tex->last_chunk_height : tex->chunk_height); + if(tex->chunks[x + y * tex->num_chunks_wide] == NULL) { + failed_at = x + y * tex->num_chunks_wide; + break; + } + } + } + + if(failed_at != -1) { + for(int i = 0; i <= failed_at; ++i) { + SDL_DestroyTexture(tex->chunks[i]); + } + free(tex->chunks); + tex->num_chunks = 0; + tex->chunks = NULL; + return 1; + } + + for(int y = 0; y < tex->num_chunks_tall; ++y) { + for(int x = 0; x < tex->num_chunks_wide; ++x) { + ptrdiff_t offset = 4 * x * tex->chunk_width + + y * 4 * tex->width * tex->chunk_height; + char* addr = pixels + offset; + SDL_UpdateTexture(tex->chunks[x + y * tex->num_chunks_wide], + NULL, addr, 4 * tex->width); + } + } + + return 0; +} + +void imv_texture_draw(struct imv_texture *tex, int bx, int by, double scale) +{ + int offset_x = 0; + int offset_y = 0; + for(int y = 0; y < tex->num_chunks_tall; ++y) { + for(int x = 0; x < tex->num_chunks_wide; ++x) { + int img_w, img_h, img_access; + unsigned int img_format; + SDL_QueryTexture(tex->chunks[x + y * tex->num_chunks_wide], + &img_format, &img_access, &img_w, &img_h); + SDL_Rect view_area = { + bx + offset_x, + by + offset_y, + img_w * scale, + img_h * scale + }; + SDL_RenderCopy(tex->renderer, + tex->chunks[x + y * tex->num_chunks_wide], NULL, &view_area); + offset_x += tex->chunk_width * scale; + } + offset_x = 0; + offset_y += tex->chunk_height * scale; + } +} diff --git a/texture.h b/texture.h new file mode 100644 index 0000000..cae0d33 --- /dev/null +++ b/texture.h @@ -0,0 +1,27 @@ +#ifndef IMV_TEXTURE_H +#define IMV_TEXTURE_H + +#include <SDL2/SDL.h> +#include <FreeImage.h> + +struct imv_texture { + int width; //width of the texture overall + int height; //height of the texture overall + int num_chunks; //number of chunks allocated + SDL_Texture **chunks; //array of chunks + int num_chunks_wide; //number of chunks per row of the image + int num_chunks_tall; //number of chunks per column of the image + int chunk_width; //chunk width + int chunk_height; //chunk height + int last_chunk_width; //width of rightmost chunk + int last_chunk_height; //height of bottommost chunk + SDL_Renderer *renderer; //SDL renderer to draw to +}; + +void imv_init_texture(struct imv_texture *tex, SDL_Renderer *r); +void imv_destroy_texture(struct imv_texture *tex); + +int imv_texture_set_image(struct imv_texture *tex, FIBITMAP *image); +void imv_texture_draw(struct imv_texture *tex, int x, int y, double scale); + +#endif |