-
Notifications
You must be signed in to change notification settings - Fork 94
/
glDrawRangeElements.xhtml
140 lines (136 loc) · 12.2 KB
/
glDrawRangeElements.xhtml
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
<div class="refentry" lang="en" xml:lang="en"><a id="glDrawRangeElements"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glDrawRangeElements — render primitives from array data</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table><tr><td><code class="funcdef">void <b class="fsfunc">glDrawRangeElements</b>(</code></td><td>GLenum </td><td><var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLuint </td><td><var class="pdparam">start</var>, </td></tr><tr><td> </td><td>GLuint </td><td><var class="pdparam">end</var>, </td></tr><tr><td> </td><td>GLsizei </td><td><var class="pdparam">count</var>, </td></tr><tr><td> </td><td>GLenum </td><td><var class="pdparam">type</var>, </td></tr><tr><td> </td><td>const GLvoid * </td><td><var class="pdparam">indices</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>mode</code></em></span></dt><dd><p>
Specifies what kind of primitives to render.
Symbolic constants
<code class="constant">GL_POINTS</code>,
<code class="constant">GL_LINE_STRIP</code>,
<code class="constant">GL_LINE_LOOP</code>,
<code class="constant">GL_LINES</code>,
<code class="constant">GL_TRIANGLE_STRIP</code>,
<code class="constant">GL_TRIANGLE_FAN</code>,
<code class="constant">GL_TRIANGLES</code>,
<code class="constant">GL_QUAD_STRIP</code>,
<code class="constant">GL_QUADS</code>,
and <code class="constant">GL_POLYGON</code> are accepted.
</p></dd><dt><span class="term"><em class="parameter"><code>start</code></em></span></dt><dd><p>
Specifies the minimum array index contained in <em class="parameter"><code>indices</code></em>.
</p></dd><dt><span class="term"><em class="parameter"><code>end</code></em></span></dt><dd><p>
Specifies the maximum array index contained in <em class="parameter"><code>indices</code></em>.
</p></dd><dt><span class="term"><em class="parameter"><code>count</code></em></span></dt><dd><p>
Specifies the number of elements to be rendered.
</p></dd><dt><span class="term"><em class="parameter"><code>type</code></em></span></dt><dd><p>
Specifies the type of the values in <em class="parameter"><code>indices</code></em>. Must be one of
<code class="constant">GL_UNSIGNED_BYTE</code>, <code class="constant">GL_UNSIGNED_SHORT</code>, or
<code class="constant">GL_UNSIGNED_INT</code>.
</p></dd><dt><span class="term"><em class="parameter"><code>indices</code></em></span></dt><dd><p>
Specifies a pointer to the location where the indices are stored.
</p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
<code class="function">glDrawRangeElements</code> is a restricted form of <a class="citerefentry" href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>. <em class="parameter"><code>mode</code></em>, <em class="parameter"><code>start</code></em>, <em class="parameter"><code>end</code></em>,
and <em class="parameter"><code>count</code></em> match the corresponding arguments to <a class="citerefentry" href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>, with
the additional constraint that all values in the arrays <em class="parameter"><code>count</code></em> must lie
between <em class="parameter"><code>start</code></em> and <em class="parameter"><code>end</code></em>, inclusive.
</p><p>
Implementations denote recommended maximum amounts of vertex and
index data,
which may be queried by calling <a class="citerefentry" href="glGet"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument
<code class="constant">GL_MAX_ELEMENTS_VERTICES</code> and <code class="constant">GL_MAX_ELEMENTS_INDICES</code>.
If
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">end</mi>
<mo>-</mo>
<mi mathvariant="italic">start</mi>
<mo>+</mo>
<mn>1</mn>
</mrow>
</math>
is greater than the value of
<code class="constant">GL_MAX_ELEMENTS_VERTICES</code>, or if <em class="parameter"><code>count</code></em> is greater than the value of
<code class="constant">GL_MAX_ELEMENTS_INDICES</code>, then the call may operate at reduced
performance. There is no requirement that all vertices in the range
<math overflow="scroll">
<mfenced open="[" close="]">
<mi mathvariant="italic">start</mi>
<mi mathvariant="italic">end</mi>
</mfenced>
</math>
be referenced. However, the implementation may
partially process unused vertices, reducing performance from what could
be achieved with an optimal index set.
</p><p>
When <code class="function">glDrawRangeElements</code> is called, it uses <em class="parameter"><code>count</code></em> sequential elements from an
enabled array, starting at <em class="parameter"><code>start</code></em> to construct a sequence of
geometric primitives. <em class="parameter"><code>mode</code></em> specifies what kind of primitives are
constructed, and how the array elements construct these primitives. If
more than one array is enabled, each is used. If
<code class="constant">GL_VERTEX_ARRAY</code> is not enabled, no geometric primitives are
constructed.
</p><p>
Vertex attributes that are modified by <code class="function">glDrawRangeElements</code> have an
unspecified value after <code class="function">glDrawRangeElements</code> returns. For example, if
<code class="constant">GL_COLOR_ARRAY</code> is enabled, the value of the current color is
undefined after <code class="function">glDrawRangeElements</code> executes. Attributes that aren't
modified maintain their previous values.
</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
<code class="function">glDrawRangeElements</code> is available only if the GL version is 1.2 or greater.
</p><p>
<code class="function">glDrawRangeElements</code> is included in display lists. If <code class="function">glDrawRangeElements</code> is entered into a
display list,
the necessary array data (determined by the array pointers and
enables) is also
entered into the display list. Because the array pointers and
enables are client-side state, their values affect display lists
when the lists are created, not when the lists are executed.
</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
It is an error for indices to lie outside the range
<math overflow="scroll">
<mfenced open="[" close="]">
<mi mathvariant="italic">start</mi>
<mi mathvariant="italic">end</mi>
</mfenced>
</math>,
but implementations may not check for this situation. Such indices
cause implementation-dependent behavior.
</p><p>
<code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not an accepted value.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> is generated if <em class="parameter"><code>count</code></em> is negative.
</p><p>
<code class="constant">GL_INVALID_VALUE</code> is generated if
<math overflow="scroll">
<mrow>
<mi mathvariant="italic">end</mi>
<mo><</mo>
<mi mathvariant="italic">start</mi>
</mrow>
</math>.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if a non-zero buffer object name is bound to an
enabled array or the element array and the buffer object's data store is currently mapped.
</p><p>
<code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glDrawRangeElements</code> is executed between
the execution of <a class="citerefentry" href="glBegin"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a> and the corresponding <a class="citerefentry" href="glEnd"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
</p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
<a class="citerefentry" href="glGet"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_ELEMENTS_VERTICES</code>
</p><p>
<a class="citerefentry" href="glGet"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAX_ELEMENTS_INDICES</code>
</p></div>
{$pipelinestall}{$examples}
<div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
<a class="citerefentry" href="glArrayElement"><span class="citerefentry"><span class="refentrytitle">glArrayElement</span></span></a>,
<a class="citerefentry" href="glColorPointer"><span class="citerefentry"><span class="refentrytitle">glColorPointer</span></span></a>,
<a class="citerefentry" href="glDrawArrays"><span class="citerefentry"><span class="refentrytitle">glDrawArrays</span></span></a>,
<a class="citerefentry" href="glDrawElements"><span class="citerefentry"><span class="refentrytitle">glDrawElements</span></span></a>,
<a class="citerefentry" href="glEdgeFlagPointer"><span class="citerefentry"><span class="refentrytitle">glEdgeFlagPointer</span></span></a>,
<a class="citerefentry" href="glGetPointerv"><span class="citerefentry"><span class="refentrytitle">glGetPointerv</span></span></a>,
<a class="citerefentry" href="glIndexPointer"><span class="citerefentry"><span class="refentrytitle">glIndexPointer</span></span></a>,
<a class="citerefentry" href="glInterleavedArrays"><span class="citerefentry"><span class="refentrytitle">glInterleavedArrays</span></span></a>,
<a class="citerefentry" href="glNormalPointer"><span class="citerefentry"><span class="refentrytitle">glNormalPointer</span></span></a>,
<a class="citerefentry" href="glSecondaryColorPointer"><span class="citerefentry"><span class="refentrytitle">glSecondaryColorPointer</span></span></a>,
<a class="citerefentry" href="glTexCoordPointer"><span class="citerefentry"><span class="refentrytitle">glTexCoordPointer</span></span></a>,
<a class="citerefentry" href="glVertexPointer"><span class="citerefentry"><span class="refentrytitle">glVertexPointer</span></span></a>
</p></div><div class="refsect1" lang="en" xml:lang="en"><div id="Copyright"><h2>Copyright</h2><p>
Copyright © 1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
<a class="ulink" href="https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/" target="_top">https://web.archive.org/web/20171022161616/http://oss.sgi.com/projects/FreeB/</a>.
</p></div></div></div>