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 struct texture *load_texture(const char *fname)
  22 {
  23         struct img_pixmap img;
  24         struct texture *tex;
  25         int ifmt;
  26
  27         img_init(&img);
  28         if(img_load(&img, fname) == -1) {
  29                 fprintf(stderr, "failed to load texture: %s\n", fname);
  30                 return 0;
  31         }
  32         ifmt = gl_ifmt[opt.srgb][img.fmt];
  33
  34         if(!(tex = malloc(sizeof *tex))) {
  35                 img_destroy(&img);
  36                 fprintf(stderr, "failed to allocate texture\n");
  37                 return 0;
  38         }
  39
  40         glGenTextures(1, &tex->id);
  41         glBindTexture(GL_TEXTURE_2D, tex->id);
  42         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
  43         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
  44         glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP_SGIS, 1);
  45         glTexImage2D(GL_TEXTURE_2D, 0, ifmt, img.width, img.height, 0, gl_fmt[img.fmt],
  46                         gl_type[img.fmt], img.pixels);
  47
  48         tex->width = img.width;
  49         tex->height = img.height;
  50         tex->pixels = img.pixels;
  51         return tex;
  52 }
  53
  54 void free_texture(struct texture *tex)
  55 {
  56         if(!tex) return;
  57
  58         if(tex->id) {
  59                 glDeleteTextures(1, &tex->id);
  60         }
  61
  62         free(tex->pixels);
  63         free(tex);
  64 }