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<STRONG>NAME</STRONG>
<STRONG>glDrawElements</STRONG> - render primitives from array data
<STRONG>C</STRONG> <STRONG>SPECIFICATION</STRONG>
void <STRONG>glDrawElements</STRONG>( GLenum <EM>mode</EM>,
GLsizei <EM>count</EM>,
GLenum <EM>type</EM>,
const GLvoid *<EM>indices</EM> )
<STRONG>PARAMETERS</STRONG>
<EM>mode</EM> Specifies what kind of primitives to render.
Symbolic constants <STRONG>GL_POINTS</STRONG>, <STRONG>GL_LINE_STRIP</STRONG>,
<STRONG>GL_LINE_LOOP</STRONG>, <STRONG>GL_LINES</STRONG>, <STRONG>GL_TRIANGLE_STRIP</STRONG>,
<STRONG>GL_TRIANGLE_FAN</STRONG>, <STRONG>GL_TRIANGLES</STRONG>, <STRONG>GL_QUAD_STRIP</STRONG>,
<STRONG>GL_QUADS</STRONG>, and <STRONG>GL_POLYGON</STRONG> are accepted.
<EM>count</EM> Specifies the number of elements to be rendered.
<EM>type</EM> Specifies the type of the values in <EM>indices</EM>. Must
be one of <STRONG>GL_UNSIGNED_BYTE</STRONG>, <STRONG>GL_UNSIGNED_SHORT</STRONG>, or
<STRONG>GL_UNSIGNED_INT</STRONG>.
<EM>indices</EM> Specifies a pointer to the location where the
indices are stored.
<STRONG>DESCRIPTION</STRONG>
<STRONG>glDrawElements</STRONG> specifies multiple geometric primitives with
very few subroutine calls. Instead of calling a GL function
to pass each individual vertex, normal, texture coordinate,
edge flag, or color, you can prespecify separate arrays of
vertexes, normals, and so on and use them to construct a
sequence of primitives with a single call to <STRONG>glDrawElements</STRONG>.
When <STRONG>glDrawElements</STRONG> is called, it uses <EM>count</EM> sequential
elements from an enabled array, starting at <EM>indices</EM> to
construct a sequence of geometric primitives. <EM>mode</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 <STRONG>GL_VERTEX_ARRAY</STRONG> is not enabled,
no geometric primitives are constructed.
Vertex attributes that are modified by <STRONG>glDrawElements</STRONG> have
an unspecified value after <STRONG>glDrawElements</STRONG> returns. For
example, if <STRONG>GL_COLOR_ARRAY</STRONG> is enabled, the value of the
current color is undefined after <STRONG>glDrawElements</STRONG> executes.
Attributes that aren't modified remain well defined.
<STRONG>NOTES</STRONG>
<STRONG>glDrawElements</STRONG> is available only if the GL version is 1.1 or
greater.
<STRONG>glDrawElements</STRONG> is included in display lists. If
<STRONG>glDrawElements</STRONG> 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.
<STRONG>ERRORS</STRONG>
<STRONG>GL_INVALID_ENUM</STRONG> is generated if <EM>mode</EM> is not an accepted
value.
<STRONG>GL_INVALID_VALUE</STRONG> is generated if <EM>count</EM> is negative.
<STRONG>GL_INVALID_OPERATION</STRONG> is generated if <STRONG>glDrawElements</STRONG> is
executed between the execution of <STRONG>glBegin</STRONG> and the
corresponding <STRONG>glEnd</STRONG>.
<STRONG>SEE</STRONG> <STRONG>ALSO</STRONG>
<STRONG>glArrayElement</STRONG>, <STRONG>glColorPointer</STRONG>, <STRONG>glDrawArrays</STRONG>,
<STRONG>glEdgeFlagPointer</STRONG>,
<STRONG>glGetPointerv</STRONG>, <STRONG>glIndexPointer</STRONG>, <STRONG>glInterleavedArrays</STRONG>,
<STRONG>glNormalPointer</STRONG>,
<STRONG>glTexCoordPointer</STRONG>, <STRONG>glVertexPointer</STRONG>
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