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