git.mutantstargoat.com Git - ld42_outofspace/blob - src/opengl.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include "opengl.h"
   4
   5
   6 static void GLAPIENTRY gldebug_logger(GLenum src, GLenum type, GLuint id, GLenum severity,
   7                 GLsizei len, const char *msg, const void *cls);
   8
   9 static const char *gldebug_srcstr(unsigned int src);
  10 static const char *gldebug_typestr(unsigned int type);
  11
  12 struct GLCaps glcaps;
  13
  14 int init_opengl(void)
  15 {
  16         glewInit();
  17
  18         if(GLEW_EXT_texture_filter_anisotropic) {
  19                 glGetIntegerv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &glcaps.max_aniso);
  20         }
  21         if(GLEW_ARB_tessellation_shader) {
  22                 glGetIntegerv(GL_MAX_TESS_GEN_LEVEL, &glcaps.max_tess_level);
  23         }
  24
  25         glcaps.debug = GLEW_ARB_debug_output;
  26
  27 #ifndef NDEBUG
  28         if(glcaps.debug) {
  29                 printf("Installing OpenGL debug callback\n");
  30                 glDebugMessageCallbackARB(gldebug_logger, 0);
  31         }
  32 #endif
  33
  34         return 0;
  35 }
  36
  37 int next_pow2(int x)
  38 {
  39         x--;
  40         x = (x >> 1) | x;
  41         x = (x >> 2) | x;
  42         x = (x >> 4) | x;
  43         x = (x >> 8) | x;
  44         x = (x >> 16) | x;
  45         return x + 1;
  46 }
  47
  48 void dump_gl_texture(unsigned int tex, const char *fname)
  49 {
  50         FILE *fp;
  51         int i, width, height;
  52         unsigned char *pixels, *pptr;
  53
  54         glBindTexture(GL_TEXTURE_2D, tex);
  55         glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &width);
  56         glGetTexLevelParameteriv(GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &height);
  57
  58         if(!(pixels = malloc(width * height * 4))) {
  59                 return;
  60         }
  61         pptr = pixels;
  62         glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels);
  63
  64         if(!(fp = fopen(fname, "wb"))) {
  65                 free(pixels);
  66                 return;
  67         }
  68         fprintf(fp, "P6\n%d %d\n255\n", width, height);
  69         for(i=0; i<width * height; i++) {
  70                 fputc(*pptr++, fp);
  71                 fputc(*pptr++, fp);
  72                 fputc(*pptr++, fp);
  73                 pptr++;
  74         }
  75         fclose(fp);
  76         free(pixels);
  77 }
  78
  79
  80 static void GLAPIENTRY gldebug_logger(GLenum src, GLenum type, GLuint id, GLenum severity,
  81                 GLsizei len, const char *msg, const void *cls)
  82 {
  83         static const char *fmt = "[GLDEBUG] (%s) %s: %s\n";
  84         switch(type) {
  85         case GL_DEBUG_TYPE_ERROR:
  86                 fprintf(stderr, fmt, gldebug_srcstr(src), gldebug_typestr(type), msg);
  87                 break;
  88
  89         case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
  90         case GL_DEBUG_TYPE_PORTABILITY:
  91         case GL_DEBUG_TYPE_PERFORMANCE:
  92                 printf(fmt, gldebug_srcstr(src), gldebug_typestr(type), msg);
  93                 break;
  94
  95         default:
  96                 printf(fmt, gldebug_srcstr(src), gldebug_typestr(type), msg);
  97         }
  98 }
  99
 100 static const char *gldebug_srcstr(unsigned int src)
 101 {
 102         switch(src) {
 103         case GL_DEBUG_SOURCE_API:
 104                 return "api";
 105         case GL_DEBUG_SOURCE_WINDOW_SYSTEM:
 106                 return "wsys";
 107         case GL_DEBUG_SOURCE_SHADER_COMPILER:
 108                 return "sdrc";
 109         case GL_DEBUG_SOURCE_THIRD_PARTY:
 110                 return "3rdparty";
 111         case GL_DEBUG_SOURCE_APPLICATION:
 112                 return "app";
 113         case GL_DEBUG_SOURCE_OTHER:
 114                 return "other";
 115         default:
 116                 break;
 117         }
 118         return "unknown";
 119 }
 120
 121 static const char *gldebug_typestr(unsigned int type)
 122 {
 123         switch(type) {
 124         case GL_DEBUG_TYPE_ERROR:
 125                 return "error";
 126         case GL_DEBUG_TYPE_DEPRECATED_BEHAVIOR:
 127                 return "deprecated";
 128         case GL_DEBUG_TYPE_UNDEFINED_BEHAVIOR:
 129                 return "undefined behavior";
 130         case GL_DEBUG_TYPE_PORTABILITY:
 131                 return "portability warning";
 132         case GL_DEBUG_TYPE_PERFORMANCE:
 133                 return "performance warning";
 134         case GL_DEBUG_TYPE_OTHER:
 135                 return "other";
 136         default:
 137                 break;
 138         }
 139         return "unknown";
 140 }
 141
 142 /*
 143 static const char *gldebug_sevstr(unsigned int sev)
 144 {
 145         switch(sev) {
 146         case GL_DEBUG_SEVERITY_HIGH:
 147                 return "high";
 148         case GL_DEBUG_SEVERITY_MEDIUM:
 149                 return "medium";
 150         case GL_DEBUG_SEVERITY_LOW:
 151                 return "low";
 152         default:
 153                 break;
 154         }
 155         return "unknown";
 156 }
 157 */