| 1 | <?xml version="1.0" encoding="UTF-8"?> |
| 2 | <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd"> |
| 3 | <!-- saved from url=(0013)about:internet --> |
| 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>glGetVertexAttrib - 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="glGetVertexAttrib"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glGetVertexAttrib — Return a generic vertex attribute parameter</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribdv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLdouble * </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribfv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLfloat * </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribiv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</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><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribIiv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</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><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribIuiv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLuint * </td><td><var class="pdparam">params</var><code>)</code>;</td></tr></table><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glGetVertexAttribLdv</b>(</code></td><td>GLuint </td><td><var class="pdparam">index</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">pname</var>, </td></tr><tr><td> </td><td>GLdouble * </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>index</code></em></span></dt><dd><p>Specifies the generic vertex attribute |
| 5 | parameter to be queried.</p></dd><dt><span class="term"><em class="parameter"><code>pname</code></em></span></dt><dd><p>Specifies the symbolic name of the vertex |
| 6 | attribute parameter to be queried. Accepted values are |
| 7 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING</code>, |
| 8 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_ENABLED</code>, |
| 9 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_SIZE</code>, |
| 10 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_STRIDE</code>, |
| 11 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_TYPE</code>, |
| 12 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_NORMALIZED</code>, |
| 13 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_INTEGER</code>, |
| 14 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_DIVISOR</code>, or |
| 15 | <code class="constant">GL_CURRENT_VERTEX_ATTRIB</code>.</p></dd><dt><span class="term"><em class="parameter"><code>params</code></em></span></dt><dd><p>Returns the requested data.</p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p><code class="function">glGetVertexAttrib</code> returns in |
| 16 | <em class="parameter"><code>params</code></em> the value of a generic vertex |
| 17 | attribute parameter. The generic vertex attribute to be queried |
| 18 | is specified by <em class="parameter"><code>index</code></em>, and the parameter |
| 19 | to be queried is specified by <em class="parameter"><code>pname</code></em>.</p><p>The accepted parameter names are as follows:</p><div class="variablelist"><dl><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING</code></span></dt><dd><p> |
| 20 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 21 | single value, the name of the buffer object currently bound to |
| 22 | the binding point corresponding to generic vertex attribute array |
| 23 | <em class="parameter"><code>index</code></em>. If no buffer object is bound, |
| 24 | 0 is returned. The initial value is 0.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_ENABLED</code></span></dt><dd><p> |
| 25 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 26 | single value that is non-zero (true) if the vertex |
| 27 | attribute array for <em class="parameter"><code>index</code></em> is |
| 28 | enabled and 0 (false) if it is disabled. The initial |
| 29 | value is <code class="constant">GL_FALSE</code>.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_SIZE</code></span></dt><dd><p> |
| 30 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 31 | single value, the size of the vertex attribute array |
| 32 | for <em class="parameter"><code>index</code></em>. The size is the |
| 33 | number of values for each element of the vertex |
| 34 | attribute array, and it will be 1, 2, 3, or 4. The |
| 35 | initial value is 4.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_STRIDE</code></span></dt><dd><p> |
| 36 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 37 | single value, the array stride for (number of bytes |
| 38 | between successive elements in) the vertex attribute |
| 39 | array for <em class="parameter"><code>index</code></em>. A value of 0 |
| 40 | indicates that the array elements are stored |
| 41 | sequentially in memory. The initial value is 0.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_TYPE</code></span></dt><dd><p> |
| 42 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 43 | single value, a symbolic constant indicating the |
| 44 | array type for the vertex attribute array for |
| 45 | <em class="parameter"><code>index</code></em>. Possible values are |
| 46 | <code class="constant">GL_BYTE</code>, |
| 47 | <code class="constant">GL_UNSIGNED_BYTE</code>, |
| 48 | <code class="constant">GL_SHORT</code>, |
| 49 | <code class="constant">GL_UNSIGNED_SHORT</code>, |
| 50 | <code class="constant">GL_INT</code>, |
| 51 | <code class="constant">GL_UNSIGNED_INT</code>, |
| 52 | <code class="constant">GL_FLOAT</code>, and |
| 53 | <code class="constant">GL_DOUBLE</code>. The initial value is |
| 54 | <code class="constant">GL_FLOAT</code>.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_NORMALIZED</code></span></dt><dd><p> |
| 55 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 56 | single value that is non-zero (true) if fixed-point |
| 57 | data types for the vertex attribute array indicated |
| 58 | by <em class="parameter"><code>index</code></em> are normalized when |
| 59 | they are converted to floating point, and 0 (false) |
| 60 | otherwise. The initial value is |
| 61 | <code class="constant">GL_FALSE</code>.</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_INTEGER</code></span></dt><dd><p> |
| 62 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 63 | single value that is non-zero (true) if fixed-point |
| 64 | data types for the vertex attribute array indicated |
| 65 | by <em class="parameter"><code>index</code></em> have integer data types, and 0 (false) |
| 66 | otherwise. The initial value is |
| 67 | 0 (<code class="constant">GL_FALSE</code>).</p></dd><dt><span class="term"><code class="constant">GL_VERTEX_ATTRIB_ARRAY_DIVISOR</code></span></dt><dd><p> |
| 68 | </p><p> <em class="parameter"><code>params</code></em> returns a |
| 69 | single value that is the frequency divisor used for instanced |
| 70 | rendering. See <a href="glVertexAttribDivisor.xml"><span class="citerefentry"><span class="refentrytitle">glVertexAttribDivisor</span></span></a>. |
| 71 | The initial value is 0.</p></dd><dt><span class="term"><code class="constant">GL_CURRENT_VERTEX_ATTRIB</code></span></dt><dd><p> |
| 72 | </p><p> <em class="parameter"><code>params</code></em> returns four |
| 73 | values that represent the current value for the |
| 74 | generic vertex attribute specified by index. Generic |
| 75 | vertex attribute 0 is unique in that it has no |
| 76 | current state, so an error will be generated if |
| 77 | <em class="parameter"><code>index</code></em> is 0. The initial value |
| 78 | for all other generic vertex attributes is |
| 79 | (0,0,0,1).</p><p> |
| 80 | <code class="function">glGetVertexAttribdv</code> and <code class="function">glGetVertexAttribfv</code> |
| 81 | return the current attribute values as four single-precision floating-point values; |
| 82 | <code class="function">glGetVertexAttribiv</code> reads them as floating-point values and |
| 83 | converts them to four integer values; <code class="function">glGetVertexAttribIiv</code> and |
| 84 | <code class="function">glGetVertexAttribIuiv</code> read and return them as signed or unsigned |
| 85 | integer values, respectively; <code class="function">glGetVertexAttribLdv</code> reads and returns |
| 86 | them as four double-precision floating-point values. |
| 87 | </p></dd></dl></div><p>All of the parameters except <code class="constant">GL_CURRENT_VERTEX_ATTRIB</code> |
| 88 | represent state stored in the currently bound vertex array object.</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>If an error is generated, no change is made to the |
| 89 | contents of <em class="parameter"><code>params</code></em>.</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p><code class="constant">GL_INVALID_OPERATION</code> is generated if <em class="parameter"><code>pname</code></em> |
| 90 | is not <code class="constant">GL_CURRENT_VERTEX_ATTRIB</code> and there is no |
| 91 | currently bound vertex array object.</p><p><code class="constant">GL_INVALID_VALUE</code> is generated if |
| 92 | <em class="parameter"><code>index</code></em> is greater than or equal to |
| 93 | <code class="constant">GL_MAX_VERTEX_ATTRIBS</code>.</p><p><code class="constant">GL_INVALID_ENUM</code> is generated if |
| 94 | <em class="parameter"><code>pname</code></em> is not an accepted value.</p><p><code class="constant">GL_INVALID_OPERATION</code> is generated if |
| 95 | <em class="parameter"><code>index</code></em> is 0 and |
| 96 | <em class="parameter"><code>pname</code></em> is |
| 97 | <code class="constant">GL_CURRENT_VERTEX_ATTRIB</code>.</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p><a href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> |
| 98 | with argument <code class="constant">GL_MAX_VERTEX_ATTRIBS</code></p><p><a href="glGetVertexAttribPointerv.xml"><span class="citerefentry"><span class="refentrytitle">glGetVertexAttribPointerv</span></span></a> |
| 99 | with arguments <em class="parameter"><code>index</code></em> and |
| 100 | <code class="constant">GL_VERTEX_ATTRIB_ARRAY_POINTER</code></p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p><a href="glBindAttribLocation.xml"><span class="citerefentry"><span class="refentrytitle">glBindAttribLocation</span></span></a>, |
| 101 | <a href="glBindBuffer.xml"><span class="citerefentry"><span class="refentrytitle">glBindBuffer</span></span></a>, |
| 102 | <a href="glDisableVertexAttribArray.xml"><span class="citerefentry"><span class="refentrytitle">glDisableVertexAttribArray</span></span></a>, |
| 103 | <a href="glEnableVertexAttribArray.xml"><span class="citerefentry"><span class="refentrytitle">glEnableVertexAttribArray</span></span></a>, |
| 104 | <a href="glVertexAttrib.xml"><span class="citerefentry"><span class="refentrytitle">glVertexAttrib</span></span></a>, |
| 105 | <a href="glVertexAttribDivisor.xml"><span class="citerefentry"><span class="refentrytitle">glVertexAttribDivisor</span></span></a>, |
| 106 | <a href="glVertexAttribPointer.xml"><span class="citerefentry"><span class="refentrytitle">glVertexAttribPointer</span></span></a></p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p> |
| 107 | Copyright <span class="trademark"></span>© 2003-2005 3Dlabs Inc. Ltd. |
| 108 | Copyright <span class="trademark"></span>© 2010 Khronos Group. |
| 109 | This material may be distributed subject to the terms and conditions set forth in |
| 110 | the Open Publication License, v 1.0, 8 June 1999. |
| 111 | <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>. |
| 112 | </p></div></div></body></html> |