<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html> <head> <!-- Generated by HsColour, http://www.cs.york.ac.uk/fp/darcs/hscolour/ --> <title>Graphics/Rendering/OpenGL/GL/Framebuffer.hs</title> <link type='text/css' rel='stylesheet' href='hscolour.css' /> </head> <body> <pre><a name="line-1"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-2"></a><span class='hs-comment'>-- |</span> <a name="line-3"></a><span class='hs-comment'>-- Module : Graphics.Rendering.OpenGL.GL.Framebuffer</span> <a name="line-4"></a><span class='hs-comment'>-- Copyright : (c) Sven Panne 2002-2009</span> <a name="line-5"></a><span class='hs-comment'>-- License : BSD-style (see the file libraries/OpenGL/LICENSE)</span> <a name="line-6"></a><span class='hs-comment'>-- </span> <a name="line-7"></a><span class='hs-comment'>-- Maintainer : sven.panne@aedion.de</span> <a name="line-8"></a><span class='hs-comment'>-- Stability : stable</span> <a name="line-9"></a><span class='hs-comment'>-- Portability : portable</span> <a name="line-10"></a><span class='hs-comment'>--</span> <a name="line-11"></a><span class='hs-comment'>-- This module corresponds to section 4.2 (Whole Framebuffer Operations) of the</span> <a name="line-12"></a><span class='hs-comment'>-- OpenGL 2.1 specs.</span> <a name="line-13"></a><span class='hs-comment'>--</span> <a name="line-14"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-15"></a> <a name="line-16"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>Framebuffer</span> <span class='hs-layout'>(</span> <a name="line-17"></a> <span class='hs-comment'>-- * Querying the Buffer Configuration</span> <a name="line-18"></a> <span class='hs-varid'>auxBuffers</span><span class='hs-layout'>,</span> <span class='hs-varid'>doubleBuffer</span><span class='hs-layout'>,</span> <span class='hs-varid'>stereoBuffer</span><span class='hs-layout'>,</span> <a name="line-19"></a> <span class='hs-varid'>rgbaBits</span><span class='hs-layout'>,</span> <span class='hs-varid'>stencilBits</span><span class='hs-layout'>,</span> <span class='hs-varid'>depthBits</span><span class='hs-layout'>,</span> <span class='hs-varid'>accumBits</span><span class='hs-layout'>,</span> <span class='hs-varid'>rgbaSignedComponents</span><span class='hs-layout'>,</span> <a name="line-20"></a> <a name="line-21"></a> <span class='hs-comment'>-- * Selecting a Buffer for Writing</span> <a name="line-22"></a> <span class='hs-conid'>BufferMode</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>drawBuffer</span><span class='hs-layout'>,</span> <span class='hs-varid'>drawBuffers</span><span class='hs-layout'>,</span> <span class='hs-varid'>maxDrawBuffers</span><span class='hs-layout'>,</span> <a name="line-23"></a> <a name="line-24"></a> <span class='hs-comment'>-- * Fine Control of Buffer Updates</span> <a name="line-25"></a> <span class='hs-varid'>indexMask</span><span class='hs-layout'>,</span> <span class='hs-varid'>colorMask</span><span class='hs-layout'>,</span> <span class='hs-varid'>stencilMask</span><span class='hs-layout'>,</span> <span class='hs-varid'>stencilMaskSeparate</span><span class='hs-layout'>,</span> <span class='hs-varid'>depthMask</span><span class='hs-layout'>,</span> <a name="line-26"></a> <a name="line-27"></a> <span class='hs-comment'>-- * Clearing the Buffers</span> <a name="line-28"></a> <span class='hs-conid'>ClearBuffer</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>clear</span><span class='hs-layout'>,</span> <a name="line-29"></a> <span class='hs-varid'>clearColor</span><span class='hs-layout'>,</span> <span class='hs-varid'>clearIndex</span><span class='hs-layout'>,</span> <span class='hs-varid'>clearStencil</span><span class='hs-layout'>,</span> <span class='hs-varid'>clearDepth</span><span class='hs-layout'>,</span> <span class='hs-varid'>clearAccum</span><span class='hs-layout'>,</span> <a name="line-30"></a> <a name="line-31"></a> <span class='hs-comment'>-- * The Accumulation Buffer</span> <a name="line-32"></a> <span class='hs-conid'>AccumOp</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>accum</span> <a name="line-33"></a><span class='hs-layout'>)</span> <span class='hs-keyword'>where</span> <a name="line-34"></a> <a name="line-35"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span> <span class='hs-layout'>(</span> <span class='hs-varid'>liftM4</span> <span class='hs-layout'>)</span> <a name="line-36"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span> <span class='hs-layout'>(</span> <span class='hs-varid'>genericLength</span> <span class='hs-layout'>)</span> <a name="line-37"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span> <span class='hs-layout'>(</span> <span class='hs-varid'>isJust</span><span class='hs-layout'>,</span> <span class='hs-varid'>fromJust</span> <span class='hs-layout'>)</span> <a name="line-38"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>Marshal</span><span class='hs-varop'>.</span><span class='hs-conid'>Array</span> <span class='hs-layout'>(</span> <span class='hs-varid'>withArray</span> <span class='hs-layout'>)</span> <a name="line-39"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Foreign</span><span class='hs-varop'>.</span><span class='hs-conid'>Ptr</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Ptr</span> <span class='hs-layout'>)</span> <a name="line-40"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>BufferMode</span> <span class='hs-layout'>(</span> <a name="line-41"></a> <span class='hs-conid'>BufferMode</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-varid'>marshalBufferMode</span><span class='hs-layout'>,</span> <span class='hs-varid'>unmarshalBufferMode</span> <span class='hs-layout'>)</span> <a name="line-42"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>Capability</span> <span class='hs-layout'>(</span> <a name="line-43"></a> <span class='hs-varid'>marshalCapability</span><span class='hs-layout'>,</span> <span class='hs-varid'>unmarshalCapability</span> <span class='hs-layout'>)</span> <a name="line-44"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>BasicTypes</span> <span class='hs-layout'>(</span> <a name="line-45"></a> <span class='hs-conid'>GLboolean</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLenum</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLsizei</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLint</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLuint</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLbitfield</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLfloat</span><span class='hs-layout'>,</span> <span class='hs-conid'>GLclampf</span><span class='hs-layout'>,</span> <a name="line-46"></a> <span class='hs-conid'>GLclampd</span><span class='hs-layout'>,</span> <a name="line-47"></a><span class='hs-cpp'>#ifdef __HADDOCK__</span> <a name="line-48"></a> <span class='hs-conid'>Capability</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span> <a name="line-49"></a><span class='hs-cpp'>#else</span> <a name="line-50"></a> <span class='hs-conid'>Capability</span> <a name="line-51"></a><span class='hs-cpp'>#endif</span> <a name="line-52"></a> <span class='hs-layout'>)</span> <a name="line-53"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>Extensions</span> <span class='hs-layout'>(</span> <a name="line-54"></a> <span class='hs-conid'>FunPtr</span><span class='hs-layout'>,</span> <span class='hs-varid'>unsafePerformIO</span><span class='hs-layout'>,</span> <span class='hs-conid'>Invoker</span><span class='hs-layout'>,</span> <span class='hs-varid'>getProcAddress</span> <span class='hs-layout'>)</span> <a name="line-55"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>Face</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Face</span><span class='hs-layout'>,</span> <span class='hs-varid'>marshalFace</span> <span class='hs-layout'>)</span> <a name="line-56"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>GLboolean</span> <span class='hs-layout'>(</span> <span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-layout'>)</span> <a name="line-57"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>QueryUtils</span> <span class='hs-layout'>(</span> <a name="line-58"></a> <span class='hs-conid'>GetPName</span><span class='hs-layout'>(</span><span class='hs-conid'>GetAuxBuffers</span><span class='hs-layout'>,</span><span class='hs-conid'>GetDoublebuffer</span><span class='hs-layout'>,</span><span class='hs-conid'>GetStereo</span><span class='hs-layout'>,</span><span class='hs-conid'>GetRedBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetGreenBits</span><span class='hs-layout'>,</span> <a name="line-59"></a> <span class='hs-conid'>GetBlueBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetAlphaBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetStencilBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetDepthBits</span><span class='hs-layout'>,</span> <a name="line-60"></a> <span class='hs-conid'>GetAccumRedBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetAccumGreenBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetAccumBlueBits</span><span class='hs-layout'>,</span> <a name="line-61"></a> <span class='hs-conid'>GetAccumAlphaBits</span><span class='hs-layout'>,</span><span class='hs-conid'>GetRGBASignedComponents</span><span class='hs-layout'>,</span><span class='hs-conid'>GetDrawBuffer</span><span class='hs-layout'>,</span> <a name="line-62"></a> <span class='hs-conid'>GetIndexWritemask</span><span class='hs-layout'>,</span><span class='hs-conid'>GetColorWritemask</span><span class='hs-layout'>,</span><span class='hs-conid'>GetDepthWritemask</span><span class='hs-layout'>,</span> <a name="line-63"></a> <span class='hs-conid'>GetStencilWritemask</span><span class='hs-layout'>,</span><span class='hs-conid'>GetColorClearValue</span><span class='hs-layout'>,</span><span class='hs-conid'>GetIndexClearValue</span><span class='hs-layout'>,</span> <a name="line-64"></a> <span class='hs-conid'>GetDepthClearValue</span><span class='hs-layout'>,</span><span class='hs-conid'>GetStencilClearValue</span><span class='hs-layout'>,</span><span class='hs-conid'>GetAccumClearValue</span><span class='hs-layout'>,</span> <a name="line-65"></a> <span class='hs-conid'>GetMaxDrawBuffers</span><span class='hs-layout'>,</span><span class='hs-conid'>GetDrawBufferN</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <a name="line-66"></a> <span class='hs-varid'>getInteger1</span><span class='hs-layout'>,</span> <span class='hs-varid'>getInteger4</span><span class='hs-layout'>,</span> <span class='hs-varid'>getBoolean1</span><span class='hs-layout'>,</span> <span class='hs-varid'>getBoolean4</span><span class='hs-layout'>,</span> <span class='hs-varid'>getEnum1</span><span class='hs-layout'>,</span> <span class='hs-varid'>getSizei1</span><span class='hs-layout'>,</span> <a name="line-67"></a> <span class='hs-varid'>getFloat1</span><span class='hs-layout'>,</span> <span class='hs-varid'>getFloat4</span><span class='hs-layout'>,</span> <span class='hs-varid'>getDouble1</span> <span class='hs-layout'>)</span> <a name="line-68"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>StateVar</span> <span class='hs-layout'>(</span> <a name="line-69"></a> <span class='hs-conid'>HasGetter</span><span class='hs-layout'>(</span><span class='hs-varid'>get</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>GettableStateVar</span><span class='hs-layout'>,</span> <span class='hs-varid'>makeGettableStateVar</span><span class='hs-layout'>,</span> <a name="line-70"></a> <span class='hs-conid'>SettableStateVar</span><span class='hs-layout'>,</span> <span class='hs-varid'>makeSettableStateVar</span><span class='hs-layout'>,</span> <a name="line-71"></a> <span class='hs-conid'>StateVar</span><span class='hs-layout'>,</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>)</span> <a name="line-72"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GL</span><span class='hs-varop'>.</span><span class='hs-conid'>VertexSpec</span> <span class='hs-layout'>(</span> <a name="line-73"></a> <span class='hs-conid'>Color4</span><span class='hs-layout'>(</span><span class='hs-conid'>Color4</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span> <span class='hs-conid'>Index1</span><span class='hs-layout'>(</span><span class='hs-conid'>Index1</span><span class='hs-layout'>)</span> <span class='hs-layout'>)</span> <a name="line-74"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Graphics</span><span class='hs-varop'>.</span><span class='hs-conid'>Rendering</span><span class='hs-varop'>.</span><span class='hs-conid'>OpenGL</span><span class='hs-varop'>.</span><span class='hs-conid'>GLU</span><span class='hs-varop'>.</span><span class='hs-conid'>ErrorsInternal</span> <span class='hs-layout'>(</span> <span class='hs-varid'>recordInvalidValue</span> <span class='hs-layout'>)</span> <a name="line-75"></a> <a name="line-76"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-77"></a> <a name="line-78"></a><span class='hs-cpp'>#include "HsOpenGLExt.h"</span> <a name="line-79"></a> <a name="line-80"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-81"></a> <a name="line-82"></a><span class='hs-comment'>-- | The implementation and context dependent number of auxiliary buffers.</span> <a name="line-83"></a> <a name="line-84"></a><a name="auxBuffers"></a><span class='hs-definition'>auxBuffers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>GLsizei</span> <a name="line-85"></a><span class='hs-definition'>auxBuffers</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAuxBuffers</span> <a name="line-86"></a> <a name="line-87"></a><span class='hs-comment'>-- | 'True' if front and back buffers exist.</span> <a name="line-88"></a> <a name="line-89"></a><a name="doubleBuffer"></a><span class='hs-definition'>doubleBuffer</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>Bool</span> <a name="line-90"></a><span class='hs-definition'>doubleBuffer</span> <span class='hs-keyglyph'>=</span> <a name="line-91"></a> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getBoolean1</span> <span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-conid'>GetDoublebuffer</span> <a name="line-92"></a> <a name="line-93"></a><span class='hs-comment'>-- | 'True' if left and right buffers exist.</span> <a name="line-94"></a> <a name="line-95"></a><a name="stereoBuffer"></a><span class='hs-definition'>stereoBuffer</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>Bool</span> <a name="line-96"></a><span class='hs-definition'>stereoBuffer</span> <span class='hs-keyglyph'>=</span> <a name="line-97"></a> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getBoolean1</span> <span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-conid'>GetStereo</span> <a name="line-98"></a> <a name="line-99"></a><a name="rgbaBits"></a><span class='hs-definition'>rgbaBits</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>GLsizei</span><span class='hs-layout'>)</span> <a name="line-100"></a><span class='hs-definition'>rgbaBits</span> <span class='hs-keyglyph'>=</span> <a name="line-101"></a> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <a name="line-102"></a> <span class='hs-varid'>liftM4</span> <span class='hs-conid'>Color4</span> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetRedBits</span><span class='hs-layout'>)</span> <a name="line-103"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetGreenBits</span><span class='hs-layout'>)</span> <a name="line-104"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetBlueBits</span><span class='hs-layout'>)</span> <a name="line-105"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAlphaBits</span><span class='hs-layout'>)</span> <a name="line-106"></a> <a name="line-107"></a><a name="stencilBits"></a><span class='hs-definition'>stencilBits</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>GLsizei</span> <a name="line-108"></a><span class='hs-definition'>stencilBits</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetStencilBits</span> <a name="line-109"></a> <a name="line-110"></a><a name="depthBits"></a><span class='hs-definition'>depthBits</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>GLsizei</span> <a name="line-111"></a><span class='hs-definition'>depthBits</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetDepthBits</span> <a name="line-112"></a> <a name="line-113"></a><a name="accumBits"></a><span class='hs-definition'>accumBits</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>GLsizei</span><span class='hs-layout'>)</span> <a name="line-114"></a><span class='hs-definition'>accumBits</span> <span class='hs-keyglyph'>=</span> <a name="line-115"></a> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <a name="line-116"></a> <span class='hs-varid'>liftM4</span> <span class='hs-conid'>Color4</span> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAccumRedBits</span><span class='hs-layout'>)</span> <a name="line-117"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAccumGreenBits</span><span class='hs-layout'>)</span> <a name="line-118"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAccumBlueBits</span><span class='hs-layout'>)</span> <a name="line-119"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetAccumAlphaBits</span><span class='hs-layout'>)</span> <a name="line-120"></a> <a name="line-121"></a><a name="rgbaSignedComponents"></a><span class='hs-definition'>rgbaSignedComponents</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <a name="line-122"></a><span class='hs-definition'>rgbaSignedComponents</span> <span class='hs-keyglyph'>=</span> <a name="line-123"></a> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <a name="line-124"></a> <span class='hs-varid'>getInteger4</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Color4</span> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <a name="line-125"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-varid'>g</span><span class='hs-layout'>)</span> <a name="line-126"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <a name="line-127"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalGLboolean</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <a name="line-128"></a> <span class='hs-conid'>GetRGBASignedComponents</span> <a name="line-129"></a> <a name="line-130"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-131"></a> <a name="line-132"></a><span class='hs-comment'>-- | When colors are written to the framebuffer, they are written into the color</span> <a name="line-133"></a><span class='hs-comment'>-- buffers specified by 'drawBuffer'.</span> <a name="line-134"></a><span class='hs-comment'>-- </span> <a name="line-135"></a><span class='hs-comment'>-- If more than one color buffer is selected for drawing, then blending or</span> <a name="line-136"></a><span class='hs-comment'>-- logical operations are computed and applied independently for each color</span> <a name="line-137"></a><span class='hs-comment'>-- buffer and can produce different results in each buffer.</span> <a name="line-138"></a><span class='hs-comment'>--</span> <a name="line-139"></a><span class='hs-comment'>-- Monoscopic contexts include only left buffers, and stereoscopic contexts</span> <a name="line-140"></a><span class='hs-comment'>-- include both left and right buffers. Likewise, single-buffered contexts</span> <a name="line-141"></a><span class='hs-comment'>-- include only front buffers, and double-buffered contexts include both front</span> <a name="line-142"></a><span class='hs-comment'>-- and back buffers. The context is selected at GL initialization.</span> <a name="line-143"></a><span class='hs-comment'>--</span> <a name="line-144"></a><span class='hs-comment'>-- The initial value is 'FrontBuffers' for single-buffered contexts, and</span> <a name="line-145"></a><span class='hs-comment'>-- 'BackBuffers' for double-buffered contexts.</span> <a name="line-146"></a> <a name="line-147"></a><a name="drawBuffer"></a><span class='hs-definition'>drawBuffer</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>BufferMode</span> <a name="line-148"></a><span class='hs-definition'>drawBuffer</span> <span class='hs-keyglyph'>=</span> <a name="line-149"></a> <span class='hs-varid'>makeStateVar</span> <a name="line-150"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getEnum1</span> <span class='hs-varid'>unmarshalBufferMode</span> <span class='hs-conid'>GetDrawBuffer</span><span class='hs-layout'>)</span> <a name="line-151"></a> <span class='hs-layout'>(</span><span class='hs-varid'>maybe</span> <span class='hs-varid'>recordInvalidValue</span> <span class='hs-varid'>glDrawBuffer</span> <span class='hs-varop'>.</span> <span class='hs-varid'>marshalBufferMode</span><span class='hs-layout'>)</span> <a name="line-152"></a> <a name="line-153"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glDrawBuffer"</span> <span class='hs-varid'>glDrawBuffer</span> <span class='hs-keyglyph'>::</span> <a name="line-154"></a> <span class='hs-conid'>GLenum</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-155"></a> <a name="line-156"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-157"></a> <a name="line-158"></a><span class='hs-comment'>-- | 'drawBuffers' defines the draw buffers to which all fragment colors are</span> <a name="line-159"></a><span class='hs-comment'>-- written. The draw buffers being defined correspond in order to the respective</span> <a name="line-160"></a><span class='hs-comment'>-- fragment colors. The draw buffer for fragment colors beyond those specified</span> <a name="line-161"></a><span class='hs-comment'>-- is set to 'NoBuffers'.</span> <a name="line-162"></a><span class='hs-comment'>--</span> <a name="line-163"></a><span class='hs-comment'>-- Except for 'NoBuffers', a buffer may not appear more then once in the given</span> <a name="line-164"></a><span class='hs-comment'>-- list. Specifying a buffer more then once will result in an</span> <a name="line-165"></a><span class='hs-comment'>-- 'Graphics.Rendering.OpenGL.GLU.Errors.InvalidOperation'.</span> <a name="line-166"></a><span class='hs-comment'>--</span> <a name="line-167"></a><span class='hs-comment'>-- If fixed-function fragment shading is being performed, 'drawBuffers'</span> <a name="line-168"></a><span class='hs-comment'>-- specifies a set of draw buffers into which the fragment color is written.</span> <a name="line-169"></a><span class='hs-comment'>--</span> <a name="line-170"></a><span class='hs-comment'>-- If a fragment shader writes to @gl_FragColor@, 'drawBuffers' specifies a set</span> <a name="line-171"></a><span class='hs-comment'>-- of draw buffers into which the single fragment color defined by</span> <a name="line-172"></a><span class='hs-comment'>-- @gl_FragColor@ is written. If a fragment shader writes to @gl_FragData@,</span> <a name="line-173"></a><span class='hs-comment'>-- 'drawBuffers' specifies a set of draw buffers into which each of the multiple</span> <a name="line-174"></a><span class='hs-comment'>-- fragment colors defined by @gl_FragData@ are separately written. If a</span> <a name="line-175"></a><span class='hs-comment'>-- fragment shader writes to neither @gl_FragColor@ nor @gl_FragData@, the</span> <a name="line-176"></a><span class='hs-comment'>-- values of the fragment colors following shader execution are undefined, and</span> <a name="line-177"></a><span class='hs-comment'>-- may differ for each fragment color.</span> <a name="line-178"></a> <a name="line-179"></a><a name="drawBuffers"></a><span class='hs-definition'>drawBuffers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>BufferMode</span><span class='hs-keyglyph'>]</span> <a name="line-180"></a><span class='hs-definition'>drawBuffers</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-varid'>getDrawBuffers</span> <span class='hs-varid'>setDrawBuffers</span> <a name="line-181"></a> <a name="line-182"></a><a name="getDrawBuffers"></a><span class='hs-definition'>getDrawBuffers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>BufferMode</span><span class='hs-keyglyph'>]</span> <a name="line-183"></a><span class='hs-definition'>getDrawBuffers</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <a name="line-184"></a> <span class='hs-varid'>n</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>get</span> <span class='hs-varid'>maxDrawBuffers</span> <a name="line-185"></a> <span class='hs-varid'>mapM</span> <span class='hs-layout'>(</span><span class='hs-varid'>getEnum1</span> <span class='hs-varid'>unmarshalBufferMode</span> <span class='hs-varop'>.</span> <span class='hs-conid'>GetDrawBufferN</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>[</span> <span class='hs-num'>0</span> <span class='hs-keyglyph'>..</span> <span class='hs-varid'>n</span> <span class='hs-keyglyph'>]</span> <a name="line-186"></a> <a name="line-187"></a><a name="setDrawBuffers"></a><span class='hs-definition'>setDrawBuffers</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>BufferMode</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-188"></a><span class='hs-definition'>setDrawBuffers</span> <span class='hs-varid'>modes</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span> <a name="line-189"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>ms</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>map</span> <span class='hs-varid'>marshalBufferMode</span> <span class='hs-varid'>modes</span> <a name="line-190"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>all</span> <span class='hs-varid'>isJust</span> <span class='hs-varid'>ms</span> <a name="line-191"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>withArray</span> <span class='hs-layout'>(</span><span class='hs-varid'>map</span> <span class='hs-varid'>fromJust</span> <span class='hs-varid'>ms</span><span class='hs-layout'>)</span> <span class='hs-varop'>$</span> <a name="line-192"></a> <span class='hs-varid'>glDrawBuffers</span> <span class='hs-layout'>(</span><span class='hs-varid'>genericLength</span> <span class='hs-varid'>ms</span><span class='hs-layout'>)</span> <a name="line-193"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>recordInvalidValue</span> <a name="line-194"></a> <a name="line-195"></a><span class='hs-conid'>EXTENSION_ENTRY</span><span class='hs-layout'>(</span><span class='hs-str'>"GL_ARB_draw_buffers or OpenGL 2.0"</span><span class='hs-layout'>,</span><span class='hs-varid'>glDrawBuffers</span><span class='hs-layout'>,</span><span class='hs-conid'>GLsizei</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Ptr</span> <span class='hs-conid'>GLenum</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span><span class='hs-layout'>)</span> <a name="line-196"></a> <a name="line-197"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-198"></a> <a name="line-199"></a><span class='hs-comment'>-- | Contains the maximum number of buffers that can activated via 'drawBuffers'</span> <a name="line-200"></a><span class='hs-comment'>-- or which can be simultaneously written into from within a fragment shader</span> <a name="line-201"></a><span class='hs-comment'>-- using the special output variable array @gl_FragData@. This constant</span> <a name="line-202"></a><span class='hs-comment'>-- effectively defines the size of the @gl_FragData@ array. The minimum legal</span> <a name="line-203"></a><span class='hs-comment'>-- value is 1.</span> <a name="line-204"></a> <a name="line-205"></a><a name="maxDrawBuffers"></a><span class='hs-definition'>maxDrawBuffers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GettableStateVar</span> <span class='hs-conid'>GLsizei</span> <a name="line-206"></a><span class='hs-definition'>maxDrawBuffers</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeGettableStateVar</span> <span class='hs-varop'>$</span> <span class='hs-varid'>getSizei1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetMaxDrawBuffers</span> <a name="line-207"></a> <a name="line-208"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-209"></a> <a name="line-210"></a><span class='hs-comment'>-- | Controls the writing of individual bits in the color index buffers. The</span> <a name="line-211"></a><span class='hs-comment'>-- least significant /n/ bits of its value, where /n/ is the number of bits in a</span> <a name="line-212"></a><span class='hs-comment'>-- color index buffer, specify a mask. Where a 1 appears in the mask, it is</span> <a name="line-213"></a><span class='hs-comment'>-- possible to write to the corresponding bit in the color index buffer (or</span> <a name="line-214"></a><span class='hs-comment'>-- buffers). Where a 0 appears, the corresponding bit is write-protected.</span> <a name="line-215"></a><span class='hs-comment'>--</span> <a name="line-216"></a><span class='hs-comment'>-- This mask is used only in color index mode, and it affects only the buffers</span> <a name="line-217"></a><span class='hs-comment'>-- currently selected for writing (see 'drawBuffer'). Initially, all bits are</span> <a name="line-218"></a><span class='hs-comment'>-- enabled for writing.</span> <a name="line-219"></a> <a name="line-220"></a><a name="indexMask"></a><span class='hs-definition'>indexMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>GLuint</span> <a name="line-221"></a><span class='hs-definition'>indexMask</span> <span class='hs-keyglyph'>=</span> <a name="line-222"></a> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getInteger1</span> <span class='hs-varid'>fromIntegral</span> <span class='hs-conid'>GetIndexWritemask</span><span class='hs-layout'>)</span> <span class='hs-varid'>glIndexMask</span> <a name="line-223"></a> <a name="line-224"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glIndexMask"</span> <span class='hs-varid'>glIndexMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLuint</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-225"></a> <a name="line-226"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-227"></a> <a name="line-228"></a><span class='hs-comment'>-- | Controls whether the individual color components in the framebuffer can or</span> <a name="line-229"></a><span class='hs-comment'>-- cannot be written. If the red flag is 'Disabled', for example, no change is</span> <a name="line-230"></a><span class='hs-comment'>-- made to the red component of any pixel in any of the color buffers,</span> <a name="line-231"></a><span class='hs-comment'>-- regardless of the drawing operation attempted. Initially, all color</span> <a name="line-232"></a><span class='hs-comment'>-- components can be written.</span> <a name="line-233"></a><span class='hs-comment'>--</span> <a name="line-234"></a><span class='hs-comment'>-- Changes to individual bits of components cannot be controlled. Rather,</span> <a name="line-235"></a><span class='hs-comment'>-- changes are either enabled or disabled for entire color components.</span> <a name="line-236"></a><span class='hs-comment'>-- Furthermore, this mask is used only in RGBA mode.</span> <a name="line-237"></a> <a name="line-238"></a><a name="colorMask"></a><span class='hs-definition'>colorMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>Capability</span><span class='hs-layout'>)</span> <a name="line-239"></a><span class='hs-definition'>colorMask</span> <span class='hs-keyglyph'>=</span> <a name="line-240"></a> <span class='hs-varid'>makeStateVar</span> <a name="line-241"></a> <span class='hs-layout'>(</span><span class='hs-varid'>getBoolean4</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Color4</span> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalCapability</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <a name="line-242"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalCapability</span> <span class='hs-varid'>g</span><span class='hs-layout'>)</span> <a name="line-243"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalCapability</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <a name="line-244"></a> <span class='hs-layout'>(</span><span class='hs-varid'>unmarshalCapability</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <a name="line-245"></a> <span class='hs-conid'>GetColorWritemask</span><span class='hs-layout'>)</span> <a name="line-246"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>glColorMask</span> <span class='hs-layout'>(</span><span class='hs-varid'>marshalCapability</span> <span class='hs-varid'>r</span><span class='hs-layout'>)</span> <a name="line-247"></a> <span class='hs-layout'>(</span><span class='hs-varid'>marshalCapability</span> <span class='hs-varid'>g</span><span class='hs-layout'>)</span> <a name="line-248"></a> <span class='hs-layout'>(</span><span class='hs-varid'>marshalCapability</span> <span class='hs-varid'>b</span><span class='hs-layout'>)</span> <a name="line-249"></a> <span class='hs-layout'>(</span><span class='hs-varid'>marshalCapability</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <a name="line-250"></a> <a name="line-251"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glColorMask"</span> <span class='hs-varid'>glColorMask</span> <span class='hs-keyglyph'>::</span> <a name="line-252"></a> <span class='hs-conid'>GLboolean</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLboolean</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLboolean</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLboolean</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-253"></a> <a name="line-254"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-255"></a> <a name="line-256"></a><span class='hs-comment'>-- | Controls whether the depth buffer is enabled for writing. The initial state</span> <a name="line-257"></a><span class='hs-comment'>-- is 'Enabled'.</span> <a name="line-258"></a> <a name="line-259"></a><a name="depthMask"></a><span class='hs-definition'>depthMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>Capability</span> <a name="line-260"></a><span class='hs-definition'>depthMask</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getBoolean1</span> <span class='hs-varid'>unmarshalCapability</span> <span class='hs-conid'>GetDepthWritemask</span><span class='hs-layout'>)</span> <a name="line-261"></a> <span class='hs-layout'>(</span><span class='hs-varid'>glDepthMask</span> <span class='hs-varop'>.</span> <span class='hs-varid'>marshalCapability</span><span class='hs-layout'>)</span> <a name="line-262"></a> <a name="line-263"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glDepthMask"</span> <span class='hs-varid'>glDepthMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLboolean</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-264"></a> <a name="line-265"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-266"></a> <a name="line-267"></a><span class='hs-comment'>-- | Controls the writing of individual bits in the stencil planes. The least</span> <a name="line-268"></a><span class='hs-comment'>-- significant /n/ bits of its value, where /n/ is the number of bits in the</span> <a name="line-269"></a><span class='hs-comment'>-- stencil buffer, specify a mask. Where a 1 appears in the mask, it is</span> <a name="line-270"></a><span class='hs-comment'>-- possible to write to the corresponding bit in the stencil buffer. Where a 0</span> <a name="line-271"></a><span class='hs-comment'>-- appears, the corresponding bit is write-protected.</span> <a name="line-272"></a><span class='hs-comment'>-- Initially, all bits are enabled for writing.</span> <a name="line-273"></a> <a name="line-274"></a><a name="stencilMask"></a><span class='hs-definition'>stencilMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>GLuint</span> <a name="line-275"></a><span class='hs-definition'>stencilMask</span> <span class='hs-keyglyph'>=</span> <a name="line-276"></a> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getInteger1</span> <span class='hs-varid'>fromIntegral</span> <span class='hs-conid'>GetStencilWritemask</span><span class='hs-layout'>)</span> <span class='hs-varid'>glStencilMask</span> <a name="line-277"></a> <a name="line-278"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glStencilMask"</span> <span class='hs-varid'>glStencilMask</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLuint</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-279"></a> <a name="line-280"></a><a name="stencilMaskSeparate"></a><span class='hs-definition'>stencilMaskSeparate</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Face</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>SettableStateVar</span> <span class='hs-conid'>GLuint</span> <a name="line-281"></a><span class='hs-definition'>stencilMaskSeparate</span> <span class='hs-varid'>face</span> <span class='hs-keyglyph'>=</span> <a name="line-282"></a> <span class='hs-varid'>makeSettableStateVar</span> <span class='hs-varop'>$</span> <a name="line-283"></a> <span class='hs-varid'>glStencilMaskSeparate</span> <span class='hs-layout'>(</span><span class='hs-varid'>marshalFace</span> <span class='hs-varid'>face</span><span class='hs-layout'>)</span> <a name="line-284"></a> <a name="line-285"></a><span class='hs-conid'>EXTENSION_ENTRY</span><span class='hs-layout'>(</span><span class='hs-str'>"OpenGL 2.0"</span><span class='hs-layout'>,</span><span class='hs-varid'>glStencilMaskSeparate</span><span class='hs-layout'>,</span><span class='hs-conid'>GLenum</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLuint</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span><span class='hs-layout'>)</span> <a name="line-286"></a> <a name="line-287"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-288"></a> <a name="line-289"></a><span class='hs-comment'>-- | The buffers which can be cleared with 'clear'.</span> <a name="line-290"></a> <a name="line-291"></a><a name="ClearBuffer"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>ClearBuffer</span> <span class='hs-keyglyph'>=</span> <a name="line-292"></a> <span class='hs-conid'>ColorBuffer</span> <span class='hs-comment'>-- ^ The buffers currently enabled for color writing.</span> <a name="line-293"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>AccumBuffer</span> <span class='hs-comment'>-- ^ The accumulation buffer.</span> <a name="line-294"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>StencilBuffer</span> <span class='hs-comment'>-- ^ The stencil buffer.</span> <a name="line-295"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>DepthBuffer</span> <span class='hs-comment'>-- ^ The depth buffer.</span> <a name="line-296"></a> <span class='hs-keyword'>deriving</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Eq</span><span class='hs-layout'>,</span> <span class='hs-conid'>Ord</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-layout'>)</span> <a name="line-297"></a> <a name="line-298"></a><a name="marshalClearBuffer"></a><span class='hs-definition'>marshalClearBuffer</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>ClearBuffer</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLbitfield</span> <a name="line-299"></a><span class='hs-definition'>marshalClearBuffer</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>of</span> <a name="line-300"></a> <span class='hs-conid'>ColorBuffer</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x4000</span> <a name="line-301"></a> <span class='hs-conid'>AccumBuffer</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x200</span> <a name="line-302"></a> <span class='hs-conid'>StencilBuffer</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x400</span> <a name="line-303"></a> <span class='hs-conid'>DepthBuffer</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x100</span> <a name="line-304"></a> <a name="line-305"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-306"></a> <a name="line-307"></a><span class='hs-comment'>-- | Set the bitplane area of the window to values previously selected by</span> <a name="line-308"></a><span class='hs-comment'>-- 'clearColor', 'clearIndex', 'clearDepth', 'clearStencil', and 'clearAccum'.</span> <a name="line-309"></a><span class='hs-comment'>-- Multiple color buffers can be cleared simultaneously by selecting more than</span> <a name="line-310"></a><span class='hs-comment'>-- one buffer at a time using 'drawBuffer'.</span> <a name="line-311"></a><span class='hs-comment'>--</span> <a name="line-312"></a><span class='hs-comment'>-- The pixel ownership test, the scissor test, dithering, and the buffer</span> <a name="line-313"></a><span class='hs-comment'>-- writemasks affect the operation of 'clear'. The scissor box bounds the</span> <a name="line-314"></a><span class='hs-comment'>-- cleared region. Alpha function, blend function, logical operation,</span> <a name="line-315"></a><span class='hs-comment'>-- stenciling, texure mapping, and depth-buffering are ignored by 'clear'.</span> <a name="line-316"></a><span class='hs-comment'>--</span> <a name="line-317"></a><span class='hs-comment'>-- 'clear' takes a list of buffers, indicating which buffers are to be cleared.</span> <a name="line-318"></a><span class='hs-comment'>-- If a buffer is not present, then a 'clear' directed at that buffer has no</span> <a name="line-319"></a><span class='hs-comment'>-- effect.</span> <a name="line-320"></a><span class='hs-comment'>--</span> <a name="line-321"></a><span class='hs-comment'>-- The value to which each buffer is cleared depends on the setting of the clear</span> <a name="line-322"></a><span class='hs-comment'>-- value for that buffer.</span> <a name="line-323"></a> <a name="line-324"></a><a name="clear"></a><span class='hs-definition'>clear</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>ClearBuffer</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-325"></a><span class='hs-definition'>clear</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>glClear</span> <span class='hs-varop'>.</span> <span class='hs-varid'>sum</span> <span class='hs-varop'>.</span> <span class='hs-varid'>map</span> <span class='hs-varid'>marshalClearBuffer</span> <a name="line-326"></a> <a name="line-327"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClear"</span> <span class='hs-varid'>glClear</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLbitfield</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-328"></a> <a name="line-329"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-330"></a> <a name="line-331"></a><span class='hs-comment'>-- | Controls the red, green, blue, and alpha values used by 'clear' to clear</span> <a name="line-332"></a><span class='hs-comment'>-- the color buffers. Values written into 'clearColor' are clamped to the range</span> <a name="line-333"></a><span class='hs-comment'>-- [0, 1]. Initially, all values are 0.</span> <a name="line-334"></a> <a name="line-335"></a><a name="clearColor"></a><span class='hs-definition'>clearColor</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>GLclampf</span><span class='hs-layout'>)</span> <a name="line-336"></a><span class='hs-definition'>clearColor</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getFloat4</span> <span class='hs-conid'>Color4</span> <span class='hs-conid'>GetColorClearValue</span><span class='hs-layout'>)</span> <a name="line-337"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>glClearColor</span> <span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-338"></a> <a name="line-339"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClearColor"</span> <span class='hs-varid'>glClearColor</span> <span class='hs-keyglyph'>::</span> <a name="line-340"></a> <span class='hs-conid'>GLclampf</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLclampf</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLclampf</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLclampf</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-341"></a> <a name="line-342"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-343"></a> <a name="line-344"></a><span class='hs-comment'>-- | Controls the index /c/ used by 'clear' to clear the color index buffers.</span> <a name="line-345"></a><span class='hs-comment'>-- /c/ is not clamped. Rather, /c/ is converted to a fixed-point value with</span> <a name="line-346"></a><span class='hs-comment'>-- unspecified precision to the right of the binary point. The integer part of</span> <a name="line-347"></a><span class='hs-comment'>-- this value is then masked with 2^/m/-1, where /m/ is the number of bits in a</span> <a name="line-348"></a><span class='hs-comment'>-- color index stored in the framebuffer. Initially, the value is 0.</span> <a name="line-349"></a> <a name="line-350"></a><a name="clearIndex"></a><span class='hs-definition'>clearIndex</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Index1</span> <span class='hs-conid'>GLfloat</span><span class='hs-layout'>)</span> <a name="line-351"></a><span class='hs-definition'>clearIndex</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getFloat1</span> <span class='hs-conid'>Index1</span> <span class='hs-conid'>GetIndexClearValue</span><span class='hs-layout'>)</span> <a name="line-352"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-conid'>Index1</span> <span class='hs-varid'>i</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>glClearIndex</span> <span class='hs-varid'>i</span><span class='hs-layout'>)</span> <a name="line-353"></a> <a name="line-354"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClearIndex"</span> <span class='hs-varid'>glClearIndex</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-355"></a> <a name="line-356"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-357"></a> <a name="line-358"></a><span class='hs-comment'>-- | Controls the depth value used by 'clear' to clear the depth buffer. Values</span> <a name="line-359"></a><span class='hs-comment'>-- written into 'clearDepth' are clamped to the range [0, 1]. The initial value</span> <a name="line-360"></a><span class='hs-comment'>-- is 1.</span> <a name="line-361"></a> <a name="line-362"></a><a name="clearDepth"></a><span class='hs-definition'>clearDepth</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>GLclampd</span> <a name="line-363"></a><span class='hs-definition'>clearDepth</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getDouble1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetDepthClearValue</span><span class='hs-layout'>)</span> <span class='hs-varid'>glClearDepth</span> <a name="line-364"></a> <a name="line-365"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClearDepth"</span> <span class='hs-varid'>glClearDepth</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLclampd</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-366"></a> <a name="line-367"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-368"></a> <a name="line-369"></a><span class='hs-comment'>-- | Controls the value /s/ used by 'clear' to clear the stencil buffer. /s/ is</span> <a name="line-370"></a><span class='hs-comment'>-- masked with 2^/m/-1, where /m/ is the number of bits in the stencil buffer.</span> <a name="line-371"></a><span class='hs-comment'>-- Initially, the value is 0.</span> <a name="line-372"></a> <a name="line-373"></a><a name="clearStencil"></a><span class='hs-definition'>clearStencil</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-conid'>GLint</span> <a name="line-374"></a><span class='hs-definition'>clearStencil</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getInteger1</span> <span class='hs-varid'>id</span> <span class='hs-conid'>GetStencilClearValue</span><span class='hs-layout'>)</span> <span class='hs-varid'>glClearStencil</span> <a name="line-375"></a> <a name="line-376"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClearStencil"</span> <span class='hs-varid'>glClearStencil</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLint</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-377"></a> <a name="line-378"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-379"></a> <a name="line-380"></a><span class='hs-comment'>-- | Controls the red, green, blue, and alpha values used by 'clear' to clear</span> <a name="line-381"></a><span class='hs-comment'>-- the accumulation buffer. Values written into 'clearAccum' are clamped to the</span> <a name="line-382"></a><span class='hs-comment'>-- range [-1, 1]. The initial values are all 0.</span> <a name="line-383"></a> <a name="line-384"></a><a name="clearAccum"></a><span class='hs-definition'>clearAccum</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>StateVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-conid'>GLfloat</span><span class='hs-layout'>)</span> <a name="line-385"></a><span class='hs-definition'>clearAccum</span> <span class='hs-keyglyph'>=</span> <a name="line-386"></a> <span class='hs-varid'>makeStateVar</span> <span class='hs-layout'>(</span><span class='hs-varid'>getFloat4</span> <span class='hs-conid'>Color4</span> <span class='hs-conid'>GetAccumClearValue</span><span class='hs-layout'>)</span> <a name="line-387"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-layout'>(</span><span class='hs-conid'>Color4</span> <span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>glClearAccum</span> <span class='hs-varid'>r</span> <span class='hs-varid'>g</span> <span class='hs-varid'>b</span> <span class='hs-varid'>a</span><span class='hs-layout'>)</span> <a name="line-388"></a> <a name="line-389"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glClearAccum"</span> <span class='hs-varid'>glClearAccum</span> <span class='hs-keyglyph'>::</span> <a name="line-390"></a> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-391"></a> <a name="line-392"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-393"></a> <a name="line-394"></a><span class='hs-comment'>-- | An operation on the accumulation buffer.</span> <a name="line-395"></a> <a name="line-396"></a><a name="AccumOp"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>AccumOp</span> <span class='hs-keyglyph'>=</span> <a name="line-397"></a> <span class='hs-conid'>Accum</span> <a name="line-398"></a> <span class='hs-comment'>-- ^ Obtains /R/, /G/, /B/, and /A/ values from the buffer currently</span> <a name="line-399"></a> <span class='hs-comment'>-- selected for reading (see</span> <a name="line-400"></a> <span class='hs-comment'>-- 'Graphics.Rendering.OpenGL.GL.ReadCopyPixels.readBuffer'). Each</span> <a name="line-401"></a> <span class='hs-comment'>-- component value is divided by 2^/n/-1, where /n/ is the number of bits</span> <a name="line-402"></a> <span class='hs-comment'>-- allocated to each color component in the currently selected buffer. The</span> <a name="line-403"></a> <span class='hs-comment'>-- result is a floating-point value in the range [0, 1], which is</span> <a name="line-404"></a> <span class='hs-comment'>-- multiplied by the value given to 'accum' and added to the corresponding</span> <a name="line-405"></a> <span class='hs-comment'>-- pixel component in the accumulation buffer, thereby updating the</span> <a name="line-406"></a> <span class='hs-comment'>-- accumulation buffer.</span> <a name="line-407"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Load</span> <a name="line-408"></a> <span class='hs-comment'>-- ^ Similar to 'Accum', except that the current value in the accumulation</span> <a name="line-409"></a> <span class='hs-comment'>-- buffer is not used in the calculation of the new value. That is, the</span> <a name="line-410"></a> <span class='hs-comment'>-- /R/, /G/, /B/, and /A/ values from the currently selected buffer are</span> <a name="line-411"></a> <span class='hs-comment'>-- divided by 2^/n/-1, multiplied by the value given to 'accum', and then</span> <a name="line-412"></a> <span class='hs-comment'>-- stored in the corresponding accumulation buffer cell, overwriting the</span> <a name="line-413"></a> <span class='hs-comment'>-- current value.</span> <a name="line-414"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Return</span> <a name="line-415"></a> <span class='hs-comment'>-- ^ Transfers accumulation buffer values to the color buffer or buffers</span> <a name="line-416"></a> <span class='hs-comment'>-- currently selected for writing. Each /R/, /G/, /B/, and /A/ component</span> <a name="line-417"></a> <span class='hs-comment'>-- is multiplied by the value given to 'accum', then multiplied by 2^/n/-1,</span> <a name="line-418"></a> <span class='hs-comment'>-- clamped to the range [0, 2^/n/-1], and stored in the corresponding</span> <a name="line-419"></a> <span class='hs-comment'>-- display buffer cell. The only fragment operations that are applied to</span> <a name="line-420"></a> <span class='hs-comment'>-- this transfer are pixel ownership, scissor, dithering, and color</span> <a name="line-421"></a> <span class='hs-comment'>-- writemasks.</span> <a name="line-422"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Mult</span> <a name="line-423"></a> <span class='hs-comment'>-- ^ Multiplies each /R/, /G/, /B/, and /A/ in the accumulation buffer by</span> <a name="line-424"></a> <span class='hs-comment'>-- the value given to 'accum' and returns the scaled component to its</span> <a name="line-425"></a> <span class='hs-comment'>-- corresponding accumulation buffer location.</span> <a name="line-426"></a> <span class='hs-keyglyph'>|</span> <span class='hs-conid'>Add</span> <a name="line-427"></a> <span class='hs-comment'>-- ^ Adds the value given to 'accum' to each /R/, /G/, /B/, and /A/ in the</span> <a name="line-428"></a> <span class='hs-comment'>-- accumulation buffer.</span> <a name="line-429"></a> <span class='hs-keyword'>deriving</span> <span class='hs-layout'>(</span> <span class='hs-conid'>Eq</span><span class='hs-layout'>,</span> <span class='hs-conid'>Ord</span><span class='hs-layout'>,</span> <span class='hs-conid'>Show</span> <span class='hs-layout'>)</span> <a name="line-430"></a> <a name="line-431"></a><a name="marshalAccumOp"></a><span class='hs-definition'>marshalAccumOp</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>AccumOp</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLenum</span> <a name="line-432"></a><span class='hs-definition'>marshalAccumOp</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>of</span> <a name="line-433"></a> <span class='hs-conid'>Accum</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x100</span> <a name="line-434"></a> <span class='hs-conid'>Load</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x101</span> <a name="line-435"></a> <span class='hs-conid'>Return</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x102</span> <a name="line-436"></a> <span class='hs-conid'>Mult</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x103</span> <a name="line-437"></a> <span class='hs-conid'>Add</span> <span class='hs-keyglyph'>-></span> <span class='hs-num'>0x104</span> <a name="line-438"></a> <a name="line-439"></a><span class='hs-comment'>--------------------------------------------------------------------------------</span> <a name="line-440"></a> <a name="line-441"></a><span class='hs-comment'>-- | The accumulation buffer is an extended-range color buffer. Images are not</span> <a name="line-442"></a><span class='hs-comment'>-- rendered into it. Rather, images rendered into one of the color buffers are</span> <a name="line-443"></a><span class='hs-comment'>-- added to the contents of the accumulation buffer after rendering. Effects</span> <a name="line-444"></a><span class='hs-comment'>-- such as antialiasing (of points, lines, and polygons), motion blur, and</span> <a name="line-445"></a><span class='hs-comment'>-- depth of field can be created by accumulating images generated with different</span> <a name="line-446"></a><span class='hs-comment'>-- transformation matrices.</span> <a name="line-447"></a><span class='hs-comment'>--</span> <a name="line-448"></a><span class='hs-comment'>-- Each pixel in the accumulation buffer consists of red, green, blue, and alpha</span> <a name="line-449"></a><span class='hs-comment'>-- values. The number of bits per component in the accumulation buffer depends</span> <a name="line-450"></a><span class='hs-comment'>-- on the implementation (see 'accumBits'). Regardless of the number of bits per</span> <a name="line-451"></a><span class='hs-comment'>-- component, the range of values stored by each component is [-1, 1]. The</span> <a name="line-452"></a><span class='hs-comment'>-- accumulation buffer pixels are mapped one-to-one with frame buffer pixels.</span> <a name="line-453"></a><span class='hs-comment'>--</span> <a name="line-454"></a><span class='hs-comment'>-- 'accum' operates on the accumulation buffer. The first argument selects an</span> <a name="line-455"></a><span class='hs-comment'>-- accumulation buffer operation. The second argument, is a floating-point value</span> <a name="line-456"></a><span class='hs-comment'>-- to be used in that operation, see 'AccumOp'.</span> <a name="line-457"></a><span class='hs-comment'>--</span> <a name="line-458"></a><span class='hs-comment'>-- All accumulation buffer operations are limited to the area of the current</span> <a name="line-459"></a><span class='hs-comment'>-- scissor box and applied identically to the red, green, blue, and alpha</span> <a name="line-460"></a><span class='hs-comment'>-- components of each pixel. If an 'accum' operation results in a value outside</span> <a name="line-461"></a><span class='hs-comment'>-- the range [-1, 1], the contents of an accumulation buffer pixel component</span> <a name="line-462"></a><span class='hs-comment'>-- are undefined.</span> <a name="line-463"></a><span class='hs-comment'>--</span> <a name="line-464"></a><span class='hs-comment'>-- To clear the accumulation buffer, use 'clearAccum' to specify the clear</span> <a name="line-465"></a><span class='hs-comment'>-- value, then call 'clear' with the accumulation buffer enabled.</span> <a name="line-466"></a> <a name="line-467"></a><a name="accum"></a><span class='hs-definition'>accum</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>AccumOp</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> <a name="line-468"></a><span class='hs-definition'>accum</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>glAccum</span> <span class='hs-varop'>.</span> <span class='hs-varid'>marshalAccumOp</span> <a name="line-469"></a> <a name="line-470"></a><span class='hs-keyword'>foreign</span> <span class='hs-keyword'>import</span> <span class='hs-conid'>CALLCONV</span> <span class='hs-keyword'>unsafe</span> <span class='hs-str'>"glAccum"</span> <span class='hs-varid'>glAccum</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>GLenum</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>GLfloat</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span> </pre></body> </html>
