diff --git a/include/SDL_video.h b/include/SDL_video.h index 6afc63e65a..e2bc12be33 100644 --- a/include/SDL_video.h +++ b/include/SDL_video.h @@ -221,35 +221,65 @@ typedef enum SDL_FlashOperation typedef void *SDL_GLContext; /** - * OpenGL configuration attributes + * OpenGL configuration attributes. + * + * While you can set most OpenGL attributes normally, the attributes listed + * above must be known before SDL creates the window that will be used with + * the OpenGL context. These attributes are set and read with + * SDL_GL_SetAttribute and SDL_GL_GetAttribute. + * + * In some cases, these attributes are minimum requests; the GL does not + * promise to give you exactly what you asked for. It's possible to ask for a + * 16-bit depth buffer and get a 24-bit one instead, for example, or to ask + * for no stencil buffer and still have one available. Context creation should + * fail if the GL can't provide your requested attributes at a minimum, but + * you should check to see exactly what you got. + * + * + * [Multisample anti-aliasing](http://en.wikipedia.org/wiki/Multisample_anti-aliasing) + * is a type of full screen anti-aliasing. Multipsampling defaults to off but + * can be turned on by setting SDL_GL_MULTISAMPLEBUFFERS to 1 and + * SDL_GL_MULTISAMPLESAMPLES to a value greater than 0. Typical values are 2 + * and 4. + * + * SDL_GL_CONTEXT_PROFILE_MASK determines the type of context created, while + * both SDL_GL_CONTEXT_MAJOR_VERSION and SDL_GL_CONTEXT_MINOR_VERSION + * determine which version. All three attributes must be set prior to creating + * the first window, and in general you can't change the value of + * SDL_GL_CONTEXT_PROFILE_MASK without first destroying all windows created + * with the previous setting. + * + * SDL_GL_CONTEXT_RELEASE_BEHAVIOR can be set to + * SDL_GL_CONTEXT_RELEASE_BEHAVIOR_NONE or + * SDL_GL_CONTEXT_RELEASE_BEHAVIOR_FLUSH. */ typedef enum SDL_GLattr { - SDL_GL_RED_SIZE, - SDL_GL_GREEN_SIZE, - SDL_GL_BLUE_SIZE, - SDL_GL_ALPHA_SIZE, - SDL_GL_BUFFER_SIZE, - SDL_GL_DOUBLEBUFFER, - SDL_GL_DEPTH_SIZE, - SDL_GL_STENCIL_SIZE, - SDL_GL_ACCUM_RED_SIZE, - SDL_GL_ACCUM_GREEN_SIZE, - SDL_GL_ACCUM_BLUE_SIZE, - SDL_GL_ACCUM_ALPHA_SIZE, - SDL_GL_STEREO, - SDL_GL_MULTISAMPLEBUFFERS, - SDL_GL_MULTISAMPLESAMPLES, - SDL_GL_ACCELERATED_VISUAL, - SDL_GL_RETAINED_BACKING, - SDL_GL_CONTEXT_MAJOR_VERSION, - SDL_GL_CONTEXT_MINOR_VERSION, - SDL_GL_CONTEXT_EGL, - SDL_GL_CONTEXT_FLAGS, - SDL_GL_CONTEXT_PROFILE_MASK, - SDL_GL_SHARE_WITH_CURRENT_CONTEXT, - SDL_GL_FRAMEBUFFER_SRGB_CAPABLE, - SDL_GL_CONTEXT_RELEASE_BEHAVIOR, + SDL_GL_RED_SIZE, /**< the minimum number of bits for the red channel of the color buffer; defaults to 3. */ + SDL_GL_GREEN_SIZE, /**< the minimum number of bits for the green channel of the color buffer; defaults to 3. */ + SDL_GL_BLUE_SIZE, /**< the minimum number of bits for the blue channel of the color buffer; defaults to 2. */ + SDL_GL_ALPHA_SIZE, /**< the minimum number of bits for the alpha channel of the color buffer; defaults to 0. */ + SDL_GL_BUFFER_SIZE, /**< the minimum number of bits for frame buffer size; defaults to 0. */ + SDL_GL_DOUBLEBUFFER, /**< whether the output is single or double buffered; defaults to double buffering on. */ + SDL_GL_DEPTH_SIZE, /**< the minimum number of bits in the depth buffer; defaults to 16. */ + SDL_GL_STENCIL_SIZE, /**< the minimum number of bits in the stencil buffer; defaults to 0. */ + SDL_GL_ACCUM_RED_SIZE, /**< the minimum number of bits for the red channel of the accumulation buffer; defaults to 0. */ + SDL_GL_ACCUM_GREEN_SIZE, /**< the minimum number of bits for the green channel of the accumulation buffer; defaults to 0. */ + SDL_GL_ACCUM_BLUE_SIZE, /**< the minimum number of bits for the blue channel of the accumulation buffer; defaults to 0. */ + SDL_GL_ACCUM_ALPHA_SIZE, /**< the minimum number of bits for the alpha channel of the accumulation buffer; defaults to 0. */ + SDL_GL_STEREO, /**< whether the output is stereo 3D; defaults to off. */ + SDL_GL_MULTISAMPLEBUFFERS, /**< the number of buffers used for multisample anti-aliasing; defaults to 0. */ + SDL_GL_MULTISAMPLESAMPLES, /**< the number of samples used around the current pixel used for multisample anti-aliasing. */ + SDL_GL_ACCELERATED_VISUAL, /**< set to 1 to require hardware acceleration, set to 0 to force software rendering; defaults to allow either. */ + SDL_GL_RETAINED_BACKING, /**< not used (deprecated). */ + SDL_GL_CONTEXT_MAJOR_VERSION, /**< OpenGL context major version. */ + SDL_GL_CONTEXT_MINOR_VERSION, /**< OpenGL context minor version. */ + SDL_GL_CONTEXT_EGL, /**< deprecated: set SDL_GL_CONTEXT_PROFILE_MASK to SDL_GL_CONTEXT_PROFILE_ES to enable instead. */ + SDL_GL_CONTEXT_FLAGS, /**< some combination of 0 or more of elements of the SDL_GLcontextFlag enumeration; defaults to 0. */ + SDL_GL_CONTEXT_PROFILE_MASK, /**< type of GL context (Core, Compatibility, ES). See SDL_GLprofile; default value depends on platform. */ + SDL_GL_SHARE_WITH_CURRENT_CONTEXT, /**< OpenGL context sharing; defaults to 0. */ + SDL_GL_FRAMEBUFFER_SRGB_CAPABLE, /**< requests sRGB capable visual; defaults to 0. (>= SDL 2.0.1) */ + SDL_GL_CONTEXT_RELEASE_BEHAVIOR, /**< sets context the release behavior; defaults to 1. (>= SDL 2.0.4) */ SDL_GL_CONTEXT_RESET_NOTIFICATION, SDL_GL_CONTEXT_NO_ERROR, SDL_GL_FLOATBUFFERS