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  1. int chooseConfig(EGLDisplay display, EGLConfig *config)
  2. {
  3. 	EGLint numConfigs = 0;
  4.  
  5. 	if(!eglGetConfigs(display, nullptr, 0, &numConfigs) || numConfigs == 0)
  6. 	{
  7. 		trace("ERROR: There are no graphics configurations available for this device");
  8. 		return 0;
  9. 	}
  10.  
  11. 	EGLConfig *configs = new EGLConfig[numConfigs];
  12.  
  13. 	eglGetConfigs(display, configs, numConfigs, &numConfigs);
  14.  
  15. 	EGLConfig bestConfig = 0;
  16.  
  17. 	EGLint bestSurfaceType = 0;
  18. 	EGLint bestRenderableType = 0;
  19. 	EGLint bestRedSize = 0;
  20. 	EGLint bestGreenSize = 0;
  21. 	EGLint bestBlueSize = 0;
  22. 	EGLint bestAlphaSize = 0;
  23. 	EGLint bestBufferSize = 0;
  24. 	EGLint bestDepthSize = 0;
  25.  
  26. 	for(int i = 0; i < numConfigs; ++i)
  27. 	{
  28. 		EGLint surfaceType;
  29. 		EGLint renderableType;
  30. 		EGLint redSize;
  31. 		EGLint greenSize;
  32. 		EGLint blueSize;
  33. 		EGLint alphaSize;
  34. 		EGLint bufferSize;
  35. 		EGLint depthSize;
  36.  
  37. 		eglGetConfigAttrib(display, configs[i], EGL_SURFACE_TYPE, &surfaceType);
  38. 		eglGetConfigAttrib(display, configs[i], EGL_RENDERABLE_TYPE, &renderableType);
  39. 		eglGetConfigAttrib(display, configs[i], EGL_RED_SIZE, &redSize);
  40. 		eglGetConfigAttrib(display, configs[i], EGL_GREEN_SIZE, &greenSize);
  41. 		eglGetConfigAttrib(display, configs[i], EGL_BLUE_SIZE, &blueSize);
  42. 		eglGetConfigAttrib(display, configs[i], EGL_ALPHA_SIZE, &alphaSize);
  43. 		eglGetConfigAttrib(display, configs[i], EGL_BUFFER_SIZE, &bufferSize);
  44. 		eglGetConfigAttrib(display, configs[i], EGL_DEPTH_SIZE, &depthSize);
  45.  
  46. 		// Must support both of these. Window bit for main window,
  47. 		// and pbuffer bit for the extra pbuffer in the aux ctx.
  48. 		int neededSurfType = EGL_WINDOW_BIT | EGL_PBUFFER_BIT;
  49. 		if(surfaceType & neededSurfType != neededSurfType)
  50. 			continue;
  51.  
  52. 		// must support gles2
  53. 		if(renderableType & EGL_OPENGL_ES2_BIT == 0)
  54. 			continue;
  55.  
  56. 		// must have at least some bits in each channel
  57. 		// example: RGB with no alpha is no good (for me)
  58. 		if(redSize == 0 || greenSize == 0 || blueSize == 0 || alphaSize == 0)
  59. 			continue;
  60.  
  61. 		// must have both a color buffer and a depth buffer
  62. 		if(bufferSize == 0 || depthSize == 0)
  63. 			continue;
  64.  
  65. 		// make sure config with most the precision is used
  66. 		if(bestConfig == nullptr
  67. 			|| renderableType > bestRenderableType
  68. 			|| redSize > bestRedSize
  69. 			|| greenSize > bestGreenSize
  70. 			|| blueSize > bestBlueSize
  71. 			|| alphaSize > bestAlphaSize
  72. 			|| bufferSize > bestBufferSize
  73. 			|| depthSize > bestDepthSize)
  74. 		{
  75. 			bestConfig = configs[i];
  76.  
  77. 			bestSurfaceType = surfaceType;
  78. 			bestRenderableType = renderableType;
  79. 			bestRedSize = redSize;
  80. 			bestGreenSize = greenSize;
  81. 			bestBlueSize = blueSize;
  82. 			bestAlphaSize = alphaSize;
  83. 			bestBufferSize = bufferSize;
  84. 			bestDepthSize = depthSize;
  85. 		}
  86. 	}
  87.  
  88. 	delete [] configs;
  89.  
  90. 	// a config was found that matches my minimum requirements
  91. 	if(bestConfig != 0)
  92. 	{
  93. 		*config = bestConfig;
  94.  
  95. 		trace("Using Display Configuration:");
  96. 		trace("EGL_SURFACE_TYPE    - ", bestSurfaceType);
  97. 		trace("EGL_RENDERABLE_TYPE - ", bestRenderableType);
  98. 		trace("EGL_RED_SIZE        - ", bestRedSize);
  99. 		trace("EGL_GREEN_SIZE      - ", bestGreenSize);
  100. 		trace("EGL_BLUE_SIZE       - ", bestBlueSize);
  101. 		trace("EGL_ALPHA_SIZE      - ", bestAlphaSize);
  102. 		trace("EGL_BUFFER_SIZE     - ", bestBufferSize);
  103. 		trace("EGL_DEPTH_SIZE      - ", bestDepthSize);
  104. 		trace("-----------------------------");
  105.  
  106. 		return 1;
  107. 	}
  108.  
  109. 	// no config found.
  110. 	return 0;
  111. }
  112.  
Compilation error #stdin compilation error #stdout 0s 0KB
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stdin
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Standard input is empty
compilation info 
prog.cpp:1:18: error: 'EGLDisplay' was not declared in this scope
 int chooseConfig(EGLDisplay display, EGLConfig *config)
                  ^
prog.cpp:1:38: error: 'EGLConfig' was not declared in this scope
 int chooseConfig(EGLDisplay display, EGLConfig *config)
                                      ^
prog.cpp:1:49: error: 'config' was not declared in this scope
 int chooseConfig(EGLDisplay display, EGLConfig *config)
                                                 ^
prog.cpp:1:55: error: expression list treated as compound expression in initializer [-fpermissive]
 int chooseConfig(EGLDisplay display, EGLConfig *config)
                                                       ^
prog.cpp:2:1: error: expected ',' or ';' before '{' token
 {
 ^
stdout
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Standard output is empty
https://ideone.com/etNRSW
language:
C++14 (gcc 8.3)
created:
8 years ago
visibility:
public

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