upstream-doc/man4/xhtml/glGetFramebufferAttachmentParameter.xml

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   4 <?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glGetFramebufferAttachmentParameteriv - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glGetFramebufferAttachmentParameter"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetFramebufferAttachmentParameteriv — retrieve information about attachments of a bound framebuffer object</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glGetFramebufferAttachmentParameteriv</b>(</code></td><td>GLenum  </td><td><var class="pdparam">target</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">attachment</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLint * </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>target</code></em></span></dt><dd><p>
   5                     Specifies the target of the query operation.
   6                 </p></dd><dt><span class="term"><em class="parameter"><code>attachment</code></em></span></dt><dd><p>
   7                     Specifies the attachment within <em class="parameter"><code>target</code></em>
   8                 </p></dd><dt><span class="term"><em class="parameter"><code>pname</code></em></span></dt><dd><p>
   9                     Specifies the parameter of <em class="parameter"><code>attachment</code></em> to query.
  10                 </p></dd><dt><span class="term"><em class="parameter"><code>params</code></em></span></dt><dd><p>
  11                     Specifies the address of a variable receive the value of <em class="parameter"><code>pname</code></em> for <em class="parameter"><code>attachment</code></em>.
  12                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  13             <code class="function">glGetFramebufferAttachmentParameteriv</code> returns information about attachments of a bound framebuffer
  14             object. <em class="parameter"><code>target</code></em> specifies the framebuffer binding point and must be <code class="constant">GL_DRAW_FRAMEBUFFER</code>,
  15             <code class="constant">GL_READ_FRAMEBUFFER</code> or <code class="constant">GL_FRAMEBUFFER</code>. <code class="constant">GL_FRAMEBUFFER</code> is equivalent
  16             to <code class="constant">GL_DRAW_FRAMEBUFFER</code>.
  17         </p><p>
  18             If the default framebuffer is bound to <em class="parameter"><code>target</code></em> then <em class="parameter"><code>attachment</code></em> must be one of
  19             <code class="constant">GL_FRONT_LEFT</code>, <code class="constant">GL_FRONT_RIGHT</code>, <code class="constant">GL_BACK_LEFT</code>, or
  20             <code class="constant">GL_BACK_RIGHT</code>, identifying a color buffer, <code class="constant">GL_DEPTH</code>, identifying the depth buffer,
  21             or <code class="constant">GL_STENCIL</code>, identifying the stencil buffer.
  22         </p><p>
  23             If a framebuffer object is bound, then <em class="parameter"><code>attachment</code></em> must be one of <code class="constant">GL_COLOR_ATTACHMENT<span class="emphasis"><em>i</em></span></code>,
  24             <code class="constant">GL_DEPTH_ATTACHMENT</code>, <code class="constant">GL_STENCIL_ATTACHMENT</code>, or <code class="constant">GL_DEPTH_STENCIL_ATTACHMENT</code>.
  25             <span class="emphasis"><em>i</em></span> in <code class="constant">GL_COLOR_ATTACHMENT<span class="emphasis"><em>i</em></span></code> must be in the range zero to the value of
  26             <code class="constant">GL_MAX_COLOR_ATTACHMENTS</code> - 1.
  27         </p><p>
  28             If <em class="parameter"><code>attachment</code></em> is <code class="constant">GL_DEPTH_STENCIL_ATTACHMENT</code> and different objects are bound
  29             to the depth and stencil attachment points of <em class="parameter"><code>target</code></em> the query will fail. If the same object
  30             is bound to both attachment points, information about that object will be returned.
  31         </p><p>
  32             Upon successful return from <code class="function">glGetFramebufferAttachmentParameteriv</code>,  if <em class="parameter"><code>pname</code></em> is
  33             <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code>, then <em class="parameter"><code>params</code></em> will contain one of <code class="constant">GL_NONE</code>,
  34             <code class="constant">GL_FRAMEBUFFER_DEFAULT</code>, <code class="constant">GL_TEXTURE</code>, or <code class="constant">GL_RENDERBUFFER</code>, identifying the type of
  35             object which contains the attached image.  Other values accepted for <em class="parameter"><code>pname</code></em> depend on the type of object, as described below.
  36         </p><p>
  37             If the value of <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code> is <code class="constant">GL_NONE</code>, no framebuffer is bound to
  38             <em class="parameter"><code>target</code></em>. In this case querying <em class="parameter"><code>pname</code></em> <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code>
  39             will return zero, and all other queries will generate an error.
  40         </p><p>
  41             If the value of <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code> is not <code class="constant">GL_NONE</code>, these queries apply to all other
  42             framebuffer types:
  43         </p><div class="itemizedlist"><ul type="disc"><li><p>
  44                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE</code>,
  45                     <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE</code>, <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE</code>,
  46                     <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE</code>, <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE</code>,
  47                     or <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE</code>, then <em class="parameter"><code>params</code></em> will contain the number
  48                     of bits in the corresponding red, green, blue, alpha, depth, or stencil component of the specified attachment. Zero is returned
  49                     if the requested component is not present in <em class="parameter"><code>attachment</code></em>.
  50                 </p></li><li><p>
  51                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_COMPONENT_TYPE</code>, <em class="parameter"><code>params</code></em> will
  52                     contain the format of components of the specified attachment, one of <code class="constant">GL_FLOAT</code>, <em class="parameter"><code>GL_INT</code></em>,
  53                     <em class="parameter"><code>GL_UNSIGNED_INT</code></em>, <em class="parameter"><code>GL_SIGNED_NORMALIZED</code></em>, or <em class="parameter"><code>GL_UNSIGNED_NORMALIZED</code></em>
  54                     for floating-point, signed integer, unsigned integer, signed normalized fixed-point, or unsigned normalized fixed-point components
  55                     respectively. Only color buffers may have  integer components.
  56                 </p></li><li><p>
  57                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_COLOR_ENCODING</code>, <em class="parameter"><code>param</code></em> will
  58                     contain the encoding of components of the specified attachment, one of <code class="constant">GL_LINEAR</code> or <code class="constant">GL_SRGB</code>
  59                     for linear or sRGB-encoded components, respectively. Only color buffer components may be sRGB-encoded;  such components
  60                     are treated as described in sections 4.1.7 and 4.1.8.  For the default framebuffer, color encoding is determined by the implementation.
  61                     For framebuffer objects, components are sRGB-encoded if the internal format of a color attachment is one of the color-renderable SRGB
  62                     formats.
  63                 </p></li></ul></div><p>
  64             If the value of <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code> is <code class="constant">GL_RENDERBUFFER</code>, then:
  65         </p><div class="itemizedlist"><ul type="disc"><li><p>
  66                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code>, <em class="parameter"><code>params</code></em> will contain
  67                     the name of the renderbuffer object which contains the attached image.
  68                 </p></li></ul></div><p>
  69             If the value of <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code> is <code class="constant">GL_TEXTURE</code>, then:
  70         </p><div class="itemizedlist"><ul type="disc"><li><p>
  71                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code>, then <em class="parameter"><code>params</code></em> will
  72                     contain the name of the texture object which contains the attached image.
  73                 </p></li><li><p>
  74                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LEVEL</code>, then <em class="parameter"><code>params</code></em>
  75                     will contain the mipmap level of the texture object which contains the attached image.
  76                 </p></li><li><p>
  77                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_CUBE_MAP_FACE</code> and the texture object named
  78                     <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code> is a cube map texture, then <em class="parameter"><code>params</code></em> will contain the cube map
  79                     face of the cubemap texture object which contains the attached image.  Otherwise <em class="parameter"><code>params</code></em> will contain the value
  80                     zero.
  81                 </p></li><li><p>
  82                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_TEXTURE_LAYER</code> and the texture object named
  83                     <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code> is a layer of a three-dimensional texture or a one-or two-dimensional
  84                     array texture, then <em class="parameter"><code>params</code></em> will contain the number of the texture layer which contains the attached image.
  85                     Otherwise <em class="parameter"><code>params</code></em> will contain the value zero.
  86                 </p></li><li><p>
  87                     If <em class="parameter"><code>pname</code></em> is <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_LAYERED</code>, then <em class="parameter"><code>params</code></em> will
  88                     contain <code class="constant">GL_TRUE</code> if an entire level of a three-dimesional texture, cube map texture, or one-or two-dimensional
  89                     array texture is attached. Otherwise, <em class="parameter"><code>params</code></em> will contain <code class="constant">GL_FALSE</code>.
  90                 </p></li></ul></div><p>
  91             Any combinations of framebuffer type and <em class="parameter"><code>pname</code></em> not described above will generate an error.
  92         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
  93             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>target</code></em> is not one of the accepted tokens.
  94         </p><p>
  95             <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>pname</code></em> is not valid for the value of
  96             <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code>.
  97         </p><p>
  98             <code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>attachment</code></em> is not the accepted values
  99             for <em class="parameter"><code>target</code></em>.
 100         </p><p>
 101             <code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>attachment</code></em> is <code class="constant">GL_DEPTH_STENCIL_ATTACHMENT</code>
 102             and different objects are bound to the depth and stencil attachment points of <em class="parameter"><code>target</code></em>.
 103         </p><p>
 104             <code class="constant">GL_INVALID_OPERATION</code> is generated if the value of <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE</code> is
 105             <code class="constant">GL_NONE</code> and <em class="parameter"><code>pname</code></em> is not <code class="constant">GL_FRAMEBUFFER_ATTACHMENT_OBJECT_NAME</code>.
 106         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 107             <a href="glGenFramebuffers.xml"><span class="citerefentry"><span class="refentrytitle">glGenFramebuffers</span></span></a>,
 108             <a href="glBindFramebuffer.xml"><span class="citerefentry"><span class="refentrytitle">glBindFramebuffer</span></span></a>
 109         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 110             Copyright <span class="trademark"></span>© 2010-2013 Khronos Group.
 111             This material may be distributed subject to the terms and conditions set forth in
 112             the Open Publication License, v 1.0, 8 June 1999.
 113             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
 114         </p></div></div></body></html>