git.mutantstargoat.com Git - demo_prior/blob - src/texture.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include "opengl.h"
   4 #include "texture.h"
   5 #include "imago2.h"
   6 #include "opt.h"
   7
   8 static unsigned int gl_ifmt[2][NUM_IMG_FMT] = {
   9         /* opt.srgb == 0 */
  10         {GL_LUMINANCE, GL_RGB, GL_RGBA, GL_LUMINANCE16F_ARB, GL_RGB16F, GL_RGBA16F, GL_RGBA, GL_RGB},
  11         /* opt.srgb == 1 */
  12         {GL_SLUMINANCE, GL_SRGB, GL_SRGB_ALPHA, GL_LUMINANCE16F_ARB, GL_RGB16F, GL_RGBA16F, GL_SRGB_ALPHA, GL_SRGB}
  13 };
  14 static unsigned int gl_fmt[] = {
  15         GL_LUMINANCE, GL_RGB, GL_RGBA, GL_LUMINANCE, GL_RGB, GL_RGBA, GL_BGRA, GL_RGB
  16 };
  17 static unsigned int gl_type[] = {
  18         GL_UNSIGNED_BYTE, GL_UNSIGNED_BYTE, GL_UNSIGNED_BYTE, GL_FLOAT, GL_FLOAT, GL_FLOAT, GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT_5_6_5
  19 };
  20
  21
  22 struct texture *load_texture(const char *fname)
  23 {
  24         struct img_pixmap img;
  25         struct texture *tex;
  26         int ifmt;
  27
  28         img_init(&img);
  29         if(img_load(&img, fname) == -1) {
  30                 fprintf(stderr, "failed to load texture: %s\n", fname);
  31                 return 0;
  32         }
  33         ifmt = gl_ifmt[opt.srgb][img.fmt];
  34
  35         if(!(tex = malloc(sizeof *tex))) {
  36                 img_destroy(&img);
  37                 fprintf(stderr, "failed to allocate texture\n");
  38                 return 0;
  39         }
  40
  41         glGenTextures(1, &tex->id);
  42         glBindTexture(GL_TEXTURE_2D, tex->id);
  43         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
  44         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  45         glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP_SGIS, 1);
  46         glTexImage2D(GL_TEXTURE_2D, 0, ifmt, img.width, img.height, 0, gl_fmt[img.fmt],
  47                         gl_type[img.fmt], img.pixels);
  48
  49         tex->width = img.width;
  50         tex->height = img.height;
  51         tex->pixels = img.pixels;
  52         return tex;
  53 }
  54
  55 void free_texture(struct texture *tex)
  56 {
  57         if(!tex) return;
  58
  59         if(tex->id) {
  60                 glDeleteTextures(1, &tex->id);
  61         }
  62
  63         free(tex->pixels);
  64         free(tex);
  65 }