upstream-man-pages/man4/glGetInternalFormativ.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
   3               "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
   4 <refentry id="glGetInternalFormativ">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>2011</year>
   9                 <holder>Khronos Group.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glGetInternalFormativ</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glGetInternalFormativ</refname>
  17         <refpurpose>retrieve information about implementation-dependent support for internal formats</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glGetInternalFormativ</function></funcdef>
  23                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  24                 <paramdef>GLenum <parameter>internalformat</parameter></paramdef>
  25                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  26                 <paramdef>GLsizei <parameter>bufSize</parameter></paramdef>
  27                 <paramdef>GLint *<parameter>params</parameter></paramdef>
  28             </funcprototype>
  29             <funcprototype>
  30                 <funcdef>void <function>glGetInternalFormati64v</function></funcdef>
  31                 <paramdef>GLenum <parameter>target</parameter></paramdef>
  32                 <paramdef>GLenum <parameter>internalformat</parameter></paramdef>
  33                 <paramdef>GLenum <parameter>pname</parameter></paramdef>
  34                 <paramdef>GLsizei <parameter>bufSize</parameter></paramdef>
  35                 <paramdef>GLint64 *<parameter>params</parameter></paramdef>
  36             </funcprototype>
  37         </funcsynopsis>
  38     </refsynopsisdiv>
  39     <!-- eqn: ignoring delim $$ -->
  40     <refsect1 id="parameters"><title>Parameters</title>
  41         <variablelist>
  42         <varlistentry>
  43             <term><parameter>target</parameter></term>
  44             <listitem>
  45                 <para>
  46                     Indicates the usage of the internal format. <parameter>target</parameter> must be <constant>GL_TEXTURE_1D</constant>, <constant>GL_TEXTURE_1D_ARRAY</constant>,
  47                     <constant>GL_TEXTURE_2D</constant>, <constant>GL_TEXTURE_2D_ARRAY</constant>, <constant>GL_TEXTURE_3D</constant>,
  48                     <constant>GL_TEXTURE_CUBE_MAP</constant>, <constant>GL_TEXTURE_CUBE_MAP_ARRAY</constant>, <constant>GL_TEXTURE_RECTANGLE</constant>,
  49                     <constant>GL_TEXTURE_BUFFER</constant>,
  50                     <constant>GL_RENDERBUFFER</constant>, <constant>GL_TEXTURE_2D_MULTISAMPLE</constant> or <constant>GL_TEXTURE_2D_MULTISAMPLE_ARRAY</constant>.
  51                 </para>
  52             </listitem>
  53         </varlistentry>
  54         <varlistentry>
  55             <term><parameter>internalformat</parameter></term>
  56             <listitem>
  57                 <para>
  58                     Specifies the internal format about which to retrieve information.
  59                 </para>
  60             </listitem>
  61         </varlistentry>
  62         <varlistentry>
  63             <term><parameter>pname</parameter></term>
  64             <listitem>
  65                 <para>
  66                     Specifies the type of information to query.
  67                 </para>
  68             </listitem>
  69         </varlistentry>
  70         <varlistentry>
  71             <term><parameter>bufSize</parameter></term>
  72             <listitem>
  73                 <para>
  74                     Specifies the maximum number of basic machine units that may be written to <parameter>params</parameter> by the function.
  75                 </para>
  76             </listitem>
  77         </varlistentry>
  78         <varlistentry>
  79             <term><parameter>params</parameter></term>
  80             <listitem>
  81                 <para>
  82                     Specifies the address of a variable into which to write the retrieved information.
  83                 </para>
  84             </listitem>
  85         </varlistentry>
  86         </variablelist>
  87     </refsect1>
  88     <refsect1 id="description"><title>Description</title>
  89         <para>
  90             <function>glGetInternalFormativ</function> and <function>glGetInternalFormati64v</function> retrieve information about implementation-dependent support for
  91             internal formats. <parameter>target</parameter> indicates the target with which the internal format will
  92             be used and must be one of <constant>GL_RENDERBUFFER</constant>, <constant>GL_TEXTURE_2D_MULTISAMPLE</constant>,
  93             or <constant>GL_TEXTURE_2D_MULTISAMPLE_ARRAY</constant>, corresponding to usage as a renderbuffer, two-dimensional
  94             multisample texture or two-dimensional multisample array texture, respectively.
  95         </para>
  96         <para>
  97             <parameter>internalformat</parameter> specifies the internal format about which to retrieve information and
  98             must be a color-renderable, depth-renderable or stencil-renderable format.
  99         </para>
 100         <para>
 101             The information retrieved will be written to memory addressed by the pointer specified in <parameter>params</parameter>. No
 102             more than <parameter>bufSize</parameter> basic machine units will be written to this memory.
 103         </para>
 104         <para>
 105             If <parameter>pname</parameter> is <constant>GL_NUM_SAMPLE_COUNTS</constant>, the number of sample counts that would be
 106             returned by querying <constant>GL_SAMPLES</constant> will be returned in <parameter>params</parameter>.
 107         </para>
 108         <para>
 109             If <parameter>pname</parameter> is <constant>GL_SAMPLES</constant>, the sample counts supported for <parameter>internalformat</parameter>
 110             and <parameter>target</parameter> are written into <parameter>params</parameter> in descending numeric order. Only positive values are returned.
 111             Querying <constant>GL_SAMPLES</constant> with <parameter>bufSize</parameter> of one will return just the maximum supported number of
 112             samples for this format. The maximum value in <constant>GL_SAMPLES</constant> is guaranteed to be at least the lowest of the following:
 113             <itemizedlist>
 114                 <listitem>The value of <constant>GL_MAX_INTEGER_SAMPLES</constant> if <parameter>internalformat</parameter> is a signed or unsigned integer format.</listitem>
 115                 <listitem>The value of <constant>GL_MAX_DEPTH_TEXTURE_SAMPLES</constant> if <parameter>internalformat</parameter> is a depth- or stencil-renderable format and
 116                 <parameter>target</parameter> is <constant>GL_TEXTURE_2D_MULTISAMPLE</constant>, <constant>GL_TEXTURE_2D_MULTISAMPLE_ARRAY</constant>.</listitem>
 117                 <listitem>The value of <constant>GL_MAX_COLOR_TEXTURE_SAMPLES</constant> if <parameter>internalformat</parameter> is a color-renderable format and
 118                 <parameter>target</parameter> is <constant>GL_TEXTURE_2D_MULTISAMPLE</constant> or <constant>GL_TEXTURE_2D_MULTISAMPLE_ARRAY</constant>.</listitem>
 119                 <listitem>The value of <constant>GL_MAX_SAMPLES</constant>.</listitem>
 120             </itemizedlist>
 121         </para>
 122         <para>
 123             If <parameter>pname</parameter> is <constant>GL_INTERNALFORMAT_SUPPORTED</constant>, <parameter>params</parameter> is set to <constant>GL_TRUE</constant> if <parameter>internalFormat</parameter>
 124             is a supported internal format for <parameter>target</parameter> and to <constant>GL_FALSE</constant> otherwise.
 125         </para>
 126         <para>
 127             If <parameter>pname</parameter> is <constant>GL_INTERNALFORMAT_PREFERRED</constant>, <parameter>params</parameter> is set to <constant>GL_TRUE</constant> if <parameter>internalFormat</parameter>
 128             is an format for <parameter>target</parameter> that is preferred by the implementation and to <constant>GL_FALSE</constant> otherwise.
 129         </para>
 130         <para>
 131             If <parameter>pname</parameter> is <constant>GL_INTERNALFORMAT_RED_SIZE</constant>, <constant>GL_INTERNALFORMAT_GREEN_SIZE</constant>,
 132             <constant>GL_INTERNALFORMAT_BLUE_SIZE</constant>, <constant>GL_INTERNALFORMAT_ALPHA_SIZE</constant>, <constant>GL_INTERNALFORMAT_DEPTH_SIZE</constant>,
 133             <constant>GL_INTERNALFORMAT_STENCIL_SIZE</constant>, or <constant>GL_INTERNALFORMAT_SHARED_SIZE</constant> then
 134             <parameter>params</parameter> is set to the actual resolutions that would be used for storing image array components
 135             for the resource for the red, green, blue, alpha, depth, stencil and shared channels respectively. If <parameter>internalFormat</parameter>
 136             is a compressed internal format, then <parameter>params</parameter> is set to the component resolution of an uncompressed internal format that produces
 137             an image of roughly the same quality as the compressed algorithm. If the internal format is unsupported, or if a particular component is
 138             not present in the format, 0 is written to <parameter>params</parameter>.
 139         </para>
 140         <para>
 141             If <parameter>pname</parameter> is <constant>GL_INTERNALFORMAT_RED_TYPE</constant>, <constant>GL_INTERNALFORMAT_GREEN_TYPE</constant>,
 142             <constant>GL_INTERNALFORMAT_BLUE_TYPE</constant>, <constant>GL_INTERNALFORMAT_ALPHA_TYPE</constant>, <constant>GL_INTERNALFORMAT_DEPTH_TYPE</constant>,
 143             or <constant>GL_INTERNALFORMAT_STENCIL_TYPE</constant> then <parameter>params</parameter> is set to a token identifying the data type used
 144             to store the respective component. If the <parameter>internalFormat</parameter> represents a compressed internal format then
 145             the types returned specify how components are interpreted after decompression.
 146         </para>
 147         <para>
 148             If <parameter>pname</parameter> is <constant>GL_MAX_WIDTH</constant>, <constant>GL_MAX_HEIGHT</constant>, <constant>GL_MAX_DEPTH</constant>,
 149             or <constant>GL_MAX_LAYERS</constant> then <parameter>pname</parameter> is filled with the maximum width, height, depth or layer count
 150             for textures with internal format <parameter>internalFormat</parameter>, respectively. If <parameter>pname</parameter> is <constant>GL_MAX_COMBINED_DIMENSIONS</constant>
 151             then <parameter>pname</parameter> is filled with the maximum combined dimensions of a texture of the specified internal format.
 152         </para>
 153         <para>
 154             If <parameter>pname</parameter> is <constant>GL_COLOR_COMPONENTS</constant> then <parameter>params</parameter> is set to the value <constant>GL_TRUE</constant>
 155             if the internal format contains any color component (i.e., red, green, blue or alpha) and to <constant>GL_FALSE</constant> otherwise. If
 156             <parameter>pname</parameter> is <constant>GL_DEPTH_COMPONENTS</constant> or <constant>GL_STENCIL_COMPONENTS</constant> then <parameter>params</parameter>
 157             is set to <constant>GL_TRUE</constant> if the internal format contains a depth or stencil component, respectively, and to <constant>GL_FALSE</constant>
 158             otherwise.
 159         </para>
 160         <para>
 161             If <parameter>pname</parameter> is <constant>GL_COLOR_RENDERABLE</constant>, <constant>GL_DEPTH_RENDERABLE</constant> or <constant>GL_STENCIL_RENDERABLE</constant>
 162             then <parameter>params</parameter> is set to <constant>GL_TRUE</constant> if the specified internal format is color, depth or stencil renderable, respectively,
 163             and to <constant>GL_FALSE</constant> otherwise.
 164         </para>
 165         <para>
 166             If <parameter>pname</parameter> is <constant>GL_FRAMEBUFFER_RENDERABLE</constant> or <constant>GL_FRAMEBUFFER_RENDERABLE_LAYERED</constant>
 167             then <parameter>params</parameter> is set to one of <constant>GL_FULL_SUPPORT</constant>,
 168             <constant>GL_CAVEAT_SUPPORT</constant> or <constant>GL_NONE</constant> to indicate that framebuffer attachments (layered attachments in the
 169             case of <constant>GL_FRAMEBUFFER_RENDERABLE_LAYERED</constant>) with that internal format are either
 170             renderable with no restrictions, renderable with some restrictions or not renderable at all.
 171         </para>
 172         <para>
 173             If <parameter>pname</parameter> is <constant>GL_FRAMEBUFFER_BLEND</constant>, <parameter>params</parameter> is set to <constant>GL_TRUE</constant>
 174             to indicate that the internal format is supported for blending operations when attached to a framebuffer, and to <constant>GL_FALSE</constant> otherwise.
 175         </para>
 176         <para>
 177             If <parameter>pname</parameter> is <constant>GL_READ_PIXELS</constant> then <parameter>params</parameter> is set to <constant>GL_FULL_SUPPORT</constant>,
 178             <constant>GL_CAVEAT_SUPPORT</constant> or <constant>GL_NONE</constant> to that either full support, limited support or no support at all is supplied
 179             for reading pixels from framebuffer attachments in the specified internal format.
 180         </para>
 181         <para>
 182             If <parameter>pname</parameter> is <constant>GL_READ_PIXELS_FORMAT</constant> or <constant>GL_READ_PIXELS_TYPE</constant> then <parameter>params</parameter>
 183             is filled with the format or type, respectively, most recommended to obtain the highest image quality and performance. For
 184             <constant>GL_READ_PIXELS_FORMAT</constant>, the value returned in <parameter>params</parameter> is a token that is accepted for
 185             the <parameter>format</parameter> argument to <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry>. For
 186             <constant>GL_READ_PIXELS_TYPE</constant>, the value returned in <parameter>params</parameter> is a token that is accepted for
 187             the <parameter>type</parameter> argument to <citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry>.
 188         </para>
 189         <para>
 190             If <parameter>pname</parameter> is <constant>GL_TEXTURE_IMAGE_FORMAT</constant> or <constant>GL_TEXTURE_IMAGE_TYPE</constant> then
 191             <parameter>params</parameter> is filled with the implementation-recommended format or type to be used in calls to
 192             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry> and other similar functions. For <constant>GL_TEXTURE_IMAGE_FORMAT</constant>,
 193             <parameter>params</parameter> is filled with a token suitable for use as the <parameter>format</parameter> argument to
 194             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>. For <constant>GL_TEXTURE_IMAGE_TYPE</constant>,
 195             <parameter>params</parameter> is filled with a token suitable for use as the <parameter>type</parameter> argument to
 196             <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>.
 197         </para>
 198         <para>
 199             If <parameter>pname</parameter> is <constant>GL_GET_TEXTURE_IMAGE_FORMAT</constant> or <constant>GL_GET_TEXTURE_IMAGE_TYPE</constant> then
 200             <parameter>params</parameter> is filled with the implementation-recommended format or type to be used in calls to
 201             <citerefentry><refentrytitle>glGetTexImage2D</refentrytitle></citerefentry> and other similar functions. For <constant>GL_GET_TEXTURE_IMAGE_FORMAT</constant>,
 202             <parameter>params</parameter> is filled with a token suitable for use as the <parameter>format</parameter> argument to
 203             <citerefentry><refentrytitle>glGetTexImage2D</refentrytitle></citerefentry>. For <constant>GL_GET_TEXTURE_IMAGE_TYPE</constant>,
 204             <parameter>params</parameter> is filled with a token suitable for use as the <parameter>type</parameter> argument to
 205             <citerefentry><refentrytitle>glGetTexImage2D</refentrytitle></citerefentry>.
 206         </para>
 207         <para>
 208             If <parameter>pname</parameter> is <constant>GL_MIPMAP</constant> then <parameter>pname</parameter> is set to <constant>GL_TRUE</constant>
 209             to indicate that the specified internal format supports mipmaps and to <constant>GL_FALSE</constant> otherwise.
 210         </para>
 211         <para>
 212             If <parameter>pname</parameter> is <constant>GL_GENERATE_MIPMAP</constant> or <constant>GL_AUTO_GENERATE_MIPMAP</constant> then <parameter>params</parameter>
 213             is indicates the level of support for manual or automatic mipmap generation for the specified internal format, respectively. Returned values
 214             may be one of <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant> and <constant>GL_NONE</constant> to indicate
 215             either full support, limited support or no support at all.
 216         </para>
 217         <para>
 218             If <parameter>pname</parameter> is <constant>GL_COLOR_ENCODING</constant> then the color encoding for the resource is returned in
 219             <parameter>params</parameter>. Possible values for color buffers are <constant>GL_LINEAR</constant> or <constant>GL_SRGB</constant>,
 220             for linear or sRGB-encoded color components, respectively. For non-color
 221             formats (such as depth or stencil), or for unsupported resources,
 222             the value <constant>GL_NONE</constant> is returned.
 223         </para>
 224         <para>
 225             If <parameter>pname</parameter> is <constant>GL_SRGB_READ</constant>, or <constant>GL_SRGB_WRITE</constant> then <parameter>params</parameter>
 226             indicates the level of support for reading and writing to sRGB encoded images, respectively. For <constant>GL_SRGB_READ</constant>,
 227             support for converting from sRGB colorspace on read operations is returned in <parameter>params</parameter> and for <constant>GL_SRGB_WRITE</constant>,
 228             support for converting to sRGB colorspace on write operations to the resource is returned in <parameter>params</parameter>. <parameter>params</parameter> may be
 229             set to <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant>, or <constant>GL_NONE</constant> to indicate
 230             full support, limited support or no support at all, respecitively.
 231         </para>
 232         <para>
 233              If <parameter>pname</parameter> is <constant>GL_FILTER</constant> the <parameter>params</parameter> is set to either <constant>GL_TRUE</constant>
 234              or <constant>GL_FALSE</constant> to indicate support or lack thereof for filter modes other than <constant>GL_NEAREST</constant> or <constant>GL_NEAREST_MIPMAP</constant>
 235              for the specified internal format.
 236          </para>
 237          <para>
 238             If <parameter>pname</parameter> is <constant>GL_VERTEX_TEXTURE</constant>, <constant>GL_TESS_CONTROL_TEXTURE</constant>, <constant>GL_TESS_EVALUATION_TEXTURE</constant>,
 239             <constant>GL_GEOMETRY_TEXTURE</constant>, <constant>GL_FRAGMENT_TEXTURE</constant>, or <constant>GL_COMPUTE_TEXTURE</constant>, then the value
 240             written to <parameter>params</parameter> indicates support for use of the resource as a source of texturing in the vertex, tessellation control,
 241             tessellation evaluation, geometry, fragment and compute shader stages, respectively. <parameter>params</parameter> may be set to
 242             <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant> or <constant>GL_NONE</constant> to indicate full support,
 243             limited support or no support at all, respectively.
 244         </para>
 245         <para>
 246             If <parameter>pname</parameter> is <constant>GL_TEXTURE_SHADOW</constant>, <constant>GL_TEXTURE_GATHER</constant> or <constant>GL_TEXTURE_GATHER_SHADOW</constant> then the value written to
 247             <parameter>params</parameter> indicates the level of support for using the resource with a shadow sampler, in gather operations or as a shadow sampler in gather operations, respectively. Returned values
 248             may be <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant> or <constant>GL_NONE</constant> to indicate full support,
 249             limited support or no support at all, respectively.
 250         </para>
 251         <para>
 252             If <parameter>pname</parameter> is <constant>GL_SHADER_IMAGE_LOAD</constant>, <constant>GL_SHADER_IMAGE_STORE</constant> or <constant>GL_SHADER_IMAGE_ATOMIC</constant>
 253             then the value returned in <parameter>params</parameter> indicates the level of support for image loads, stores and atomics for resources of the specified internal
 254             format. Returned values
 255             may be <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant> or <constant>GL_NONE</constant> to indicate full support,
 256             limited support or no support at all, respectively.
 257         </para>
 258         <para>
 259             If <parameter>pname</parameter> is <constant>GL_IMAGE_TEXEL_SIZE</constant> then the size of a texel when the resource when used as
 260             an image texture is returned in <parameter>params</parameter>. If the resource is not supported for image
 261             textures zero is returned.
 262         </para>
 263         <para>
 264             If <parameter>pname</parameter> is <constant>GL_IMAGE_COMPATIBILITY_CLASS</constant> then the compatibility class of the resource when
 265             used as an image texture is returned in <parameter>params</parameter>. The possible values
 266             returned are <constant>GL_IMAGE_CLASS_4_X_32</constant>, <constant>GL_IMAGE_CLASS_2_X_32</constant>, <constant>GL_IMAGE_CLASS_1_X_32</constant>,
 267             <constant>GL_IMAGE_CLASS_4_X_16</constant>, <constant>GL_IMAGE_CLASS_2_X_16</constant>, <constant>GL_IMAGE_CLASS_1_X_16</constant>,
 268             <constant>GL_IMAGE_CLASS_4_X_8</constant>, <constant>GL_IMAGE_CLASS_2_X_8</constant>, <constant>GL_IMAGE_CLASS_1_X_8</constant>,
 269             <constant>GL_IMAGE_CLASS_11_11_10</constant>, and <constant>GL_IMAGE_CLASS_10_10_10_2</constant>, which correspond to
 270             the 4x32, 2x32, 1x32, 4x16, 2x16, 1x16, 4x8, 2x8, 1x8, the class
 271             (a) 11/11/10 packed floating-point format, and the class (b)
 272             10/10/10/2 packed formats, respectively.
 273             If the resource is not supported for image textures, <constant>GL_NONE</constant> is returned.
 274         </para>
 275         <para>
 276             If <parameter>pname</parameter> is <constant>GL_IMAGE_PIXEL_FORMAT</constant> or <constant>GL_IMAGE_PIXEL_TYPE</constant> then
 277             the pixel format or type of the resource when used as an image texture is returned in <parameter>params</parameter>, respectively.
 278             In either case, the resource is not supported for image textures <constant>GL_NONE</constant> is returned.
 279         </para>
 280         <para>
 281             If <parameter>pname</parameter> is <constant>GL_IMAGE_FORMAT_COMPATIBILITY_TYPE</constant>, the matching criteria use for the
 282             resource when used as an image textures is returned in <parameter>params</parameter>. Possible values returned in <parameter>params</parameter> are
 283             <constant>GL_IMAGE_FORMAT_COMPATIBILITY_BY_SIZE</constant> or <constant>GL_IMAGE_FORMAT_COMPATIBILITY_BY_CLASS</constant>.
 284             If the resource is not supported for image textures, <constant>GL_NONE</constant> is returned.
 285         </para>
 286         <para>
 287             If <parameter>pname</parameter> is <constant>GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST</constant> or <constant>GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST</constant>,
 288             support for using the resource both as a source for texture sampling while it is bound as a buffer for depth or stencil test, respectively, is written to <parameter>params</parameter>.
 289             Possible values returned are <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant>, or <constant>GL_NONE</constant> to indicate
 290             full support, limited support or no support at all. If the resource or operation is not supported, <constant>GL_NONE</constant> is returned.
 291         </para>
 292         <para>
 293             If <parameter>pname</parameter> is <constant>GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE</constant> or <constant>GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE</constant>,
 294             support for using the resource both as a source for texture sampling while performing depth or stencil writes to the resources, respectively, is written to <parameter>params</parameter>.
 295             Possible values returned are <constant>GL_FULL_SUPPORT</constant>, <constant>GL_CAVEAT_SUPPORT</constant>, or <constant>GL_NONE</constant> to indicate
 296             full support, limited support or no support at all. If the resource or operation is not supported, <constant>GL_NONE</constant> is returned.
 297         </para>
 298         <para>
 299             If <parameter>pname</parameter> is <constant>GL_TEXTURE_COMPRESSED</constant> then <constant>GL_TRUE</constant> is returned in <parameter>params</parameter>
 300             if <parameter>internalformat</parameter> is a compressed internal format. <constant>GL_FALSE</constant> is returned in <parameter>params</parameter>
 301             otherwise.
 302         </para>
 303         <para>
 304             If <parameter>pname</parameter> is <constant>GL_TEXTURE_COMPRESSED_BLOCK_WIDTH</constant>, <constant>GL_TEXTURE_COMPRESSED_BLOCK_HEIGHT</constant> or
 305             <constant>GL_TEXTURE_COMPRESSED_BLOCK_SIZE</constant> then the width, height or total size, respectively of a block (in basic machine units) is returned in
 306             <parameter>params</parameter>. If the internal format is not compressed, or the resource is not supported, 0 is returned.
 307         </para>
 308         <para>
 309             If <parameter>pname</parameter> is <constant>GL_CLEAR_BUFFER</constant>, the level of support for using the resource with <citerefentry><refentrytitle>glClearBufferData</refentrytitle></citerefentry>
 310             and <citerefentry><refentrytitle>glClearBufferSubData</refentrytitle></citerefentry> is returned in <parameter>params</parameter>. Possible values returned are <constant>GL_FULL_SUPPORT</constant>,
 311             <constant>GL_CAVEAT_SUPPORT</constant>, or <constant>GL_NONE</constant> to indicate
 312             full support, limited support or no support at all, respectively. If the resource or operation is not supported, <constant>GL_NONE</constant> is returned.
 313         </para>
 314         <para>
 315             If <parameter>pname</parameter> is <constant>GL_TEXTURE_VIEW</constant>, the level of support for using the resource with the <citerefentry><refentrytitle>glTextureView</refentrytitle></citerefentry>
 316             command is returned in <parameter>params</parameter>. Possible values returned are <constant>GL_FULL_SUPPORT</constant>,
 317             <constant>GL_CAVEAT_SUPPORT</constant>, or <constant>GL_NONE</constant> to indicate
 318             full support, limited support or no support at all, respectively. If the resource or operation is not supported, <constant>GL_NONE</constant> is returned.
 319         </para>
 320         <para>
 321             If <parameter>pname</parameter> is <constant>GL_VIEW_COMPATIBILITY_CLASS</constant> then the compatibility class of the resource when
 322             used as a texture view is returned in <parameter>params</parameter>. The possible values
 323             returned are <constant>GL_VIEW_CLASS_128_BITS</constant>, <constant>GL_VIEW_CLASS_96_BITS</constant>,
 324             <constant>GL_VIEW_CLASS_64_BITS</constant>, <constant>GL_VIEW_CLASS_48_BITS</constant>, <constant>GL_VIEW_CLASS_32_BITS</constant>,
 325             <constant>GL_VIEW_CLASS_24_BITS</constant>, <constant>GL_VIEW_CLASS_16_BITS</constant>, <constant>GL_VIEW_CLASS_8_BITS</constant>,
 326             <constant>GL_VIEW_CLASS_S3TC_DXT1_RGB</constant>, <constant>GL_VIEW_CLASS_S3TC_DXT1_RGBA</constant>,
 327             <constant>GL_VIEW_CLASS_S3TC_DXT3_RGBA</constant>, <constant>GL_VIEW_CLASS_S3TC_DXT5_RGBA</constant>,
 328             <constant>GL_VIEW_CLASS_RGTC1_RED</constant>, <constant>GL_VIEW_CLASS_RGTC2_RG</constant>, <constant>GL_VIEW_CLASS_BPTC_UNORM</constant>, and
 329             <constant>GL_VIEW_CLASS_BPTC_FLOAT</constant>.
 330         </para>
 331     </refsect1>
 332     <refsect1 id="notes"><title>Notes</title>
 333         <para>
 334             <function>glGetInternalFormativ</function> is available only if the
 335             GL version is 4.2 or higher.
 336         </para>
 337         <para>
 338             The tokens
 339             <constant>GL_INTERNALFORMAT_SUPPORTED</constant>,
 340             <constant>GL_INTERNALFORMAT_PREFERRED</constant>,
 341             <constant>GL_INTERNALFORMAT_RED_SIZE</constant>,
 342             <constant>GL_INTERNALFORMAT_GREEN_SIZE</constant>,
 343             <constant>GL_INTERNALFORMAT_BLUE_SIZE</constant>,
 344             <constant>GL_INTERNALFORMAT_ALPHA_SIZE</constant>,
 345             <constant>GL_INTERNALFORMAT_DEPTH_SIZE</constant>,
 346             <constant>GL_INTERNALFORMAT_STENCIL_SIZE</constant>,
 347             <constant>GL_INTERNALFORMAT_SHARED_SIZE</constant>,
 348             <constant>GL_INTERNALFORMAT_RED_TYPE</constant>,
 349             <constant>GL_INTERNALFORMAT_GREEN_TYPE</constant>,
 350             <constant>GL_INTERNALFORMAT_BLUE_TYPE</constant>,
 351             <constant>GL_INTERNALFORMAT_ALPHA_TYPE</constant>,
 352             <constant>GL_INTERNALFORMAT_DEPTH_TYPE</constant>,
 353             <constant>GL_INTERNALFORMAT_STENCIL_TYPE</constant>,
 354             <constant>GL_MAX_WIDTH</constant>,
 355             <constant>GL_MAX_HEIGHT</constant>,
 356             <constant>GL_MAX_DEPTH</constant>,
 357             <constant>GL_MAX_LAYERS</constant>,
 358             <constant>GL_MAX_COMBINED_DIMENSIONS</constant>,
 359             <constant>GL_COLOR_COMPONENTS</constant>,
 360             <constant>GL_DEPTH_COMPONENTS</constant>,
 361             <constant>GL_STENCIL_COMPONENTS</constant>,
 362             <constant>GL_COLOR_RENDERABLE</constant>,
 363             <constant>GL_DEPTH_RENDERABLE</constant>,
 364             <constant>GL_STENCIL_RENDERABLE</constant>,
 365             <constant>GL_FRAMEBUFFER_RENDERABLE</constant>,
 366             <constant>GL_FRAMEBUFFER_RENDERABLE_LAYERED</constant>,
 367             <constant>GL_FRAMEBUFFER_BLEND</constant>,
 368             <constant>GL_READ_PIXELS</constant>,
 369             <constant>GL_READ_PIXELS_FORMAT</constant>,
 370             <constant>GL_READ_PIXELS_TYPE</constant>,
 371             <constant>GL_TEXTURE_IMAGE_FORMAT</constant>,
 372             <constant>GL_TEXTURE_IMAGE_TYPE</constant>,
 373             <constant>GL_GET_TEXTURE_IMAGE_FORMAT</constant>,
 374             <constant>GL_GET_TEXTURE_IMAGE_TYPE</constant>,
 375             <constant>GL_MIPMAP</constant>,
 376             <constant>GL_GENERATE_MIPMAP</constant>,
 377             <constant>GL_AUTO_GENERATE_MIPMAP</constant>,
 378             <constant>GL_COLOR_ENCODING</constant>,
 379             <constant>GL_SRGB_READ</constant>,
 380             <constant>GL_SRGB_WRITE</constant>,
 381             <constant>GL_SRGB_DECODE_ARB</constant>,
 382             <constant>GL_FILTER</constant>,
 383             <constant>GL_VERTEX_TEXTURE</constant>,
 384             <constant>GL_TESS_CONTROL_TEXTURE</constant>,
 385             <constant>GL_TESS_EVALUATION_TEXTURE</constant>,
 386             <constant>GL_GEOMETRY_TEXTURE</constant>,
 387             <constant>GL_FRAGMENT_TEXTURE</constant>,
 388             <constant>GL_COMPUTE_TEXTURE</constant>,
 389             <constant>GL_TEXTURE_SHADOW</constant>,
 390             <constant>GL_TEXTURE_GATHER</constant>,
 391             <constant>GL_TEXTURE_GATHER_SHADOW</constant>,
 392             <constant>GL_SHADER_IMAGE_LOAD</constant>,
 393             <constant>GL_SHADER_IMAGE_STORE</constant>,
 394             <constant>GL_SHADER_IMAGE_ATOMIC</constant>,
 395             <constant>GL_IMAGE_TEXEL_SIZE</constant>,
 396             <constant>GL_IMAGE_COMPATIBILITY_CLASS</constant>,
 397             <constant>GL_IMAGE_PIXEL_FORMAT</constant>,
 398             <constant>GL_IMAGE_PIXEL_TYPE</constant>,
 399             <constant>GL_IMAGE_FORMAT_COMPATIBILITY_TYPE</constant>,
 400             <constant>GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_TEST</constant>,
 401             <constant>GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_TEST</constant>,
 402             <constant>GL_SIMULTANEOUS_TEXTURE_AND_DEPTH_WRITE</constant>,
 403             <constant>GL_SIMULTANEOUS_TEXTURE_AND_STENCIL_WRITE</constant>,
 404             <constant>GL_TEXTURE_COMPRESSED</constant>,
 405             <constant>GL_TEXTURE_COMPRESSED_BLOCK_WIDTH</constant>,
 406             <constant>GL_TEXTURE_COMPRESSED_BLOCK_HEIGHT</constant>,
 407             <constant>GL_TEXTURE_COMPRESSED_BLOCK_SIZE</constant>,
 408             <constant>GL_CLEAR_BUFFER</constant>,
 409             <constant>GL_TEXTURE_VIEW</constant>, and
 410             <constant>GL_VIEW_COMPATIBILITY_CLASS</constant> are supported only if the GL
 411             version is 4.3 or higher.
 412         </para>
 413         </refsect1>
 414     <refsect1 id="errors"><title>Errors</title>
 415         <para>
 416             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>bufSize</parameter> is negative.
 417         </para>
 418         <para>
 419             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>pname</parameter> is not <constant>GL_SAMPLES</constant> or <constant>GL_NUM_SAMPLE_COUNTS</constant>.
 420         </para>
 421         <para>
 422             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>internalformat</parameter> is not color-, depth-, or stencil-renderable.
 423         </para>
 424         <para>
 425             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>target</parameter> is not one of <constant>GL_TEXTURE_2D_MULTISAMPLE</constant>,
 426             <constant>GL_TEXTURE_2D_MULTISAMPLE_ARRAY</constant> or <constant>GL_RENDERBUFFER</constant>.
 427         </para>
 428     </refsect1>
 429     <refsect1 id="seealso"><title>See Also</title>
 430         <para>
 431             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry>
 432         </para>
 433     </refsect1>
 434     <refsect1 id="Copyright"><title>Copyright</title>
 435         <para>
 436             Copyright <trademark class="copyright"></trademark> 2011-2012 Khronos Group.
 437             This material may be distributed subject to the terms and conditions set forth in
 438             the Open Publication License, v 1.0, 8 June 1999.
 439             <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
 440         </para>
 441     </refsect1>
 442 </refentry>