render primitives from array data
Signature
Parameters
| Variables | Description |
|---|---|
| mode |
Specifies what kind of primitives to render.
Symbolic constants
GL_POINTS
,
GL_LINE_STRIP
,
GL_LINE_LOOP
,
GL_LINES
,
GL_LINE_STRIP_ADJACENCY
,
GL_LINES_ADJACENCY
,
GL_TRIANGLE_STRIP
,
GL_TRIANGLE_FAN
,
GL_TRIANGLES
,
GL_TRIANGLE_STRIP_ADJACENCY
,
GL_TRIANGLES_ADJACENCY
and
GL_PATCHES
are accepted.
|
| count |
Specifies the number of elements to be rendered.
|
| type |
Specifies the type of the values in
indices
. Must be one of
GL_UNSIGNED_BYTE
,
GL_UNSIGNED_SHORT
, or
GL_UNSIGNED_INT
.
|
| indices |
Specifies a pointer to the location where the indices are stored.
|
Description
glDrawElements
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 vertices, normals, and so on, and use them to
construct a sequence of primitives with a single
call to
glDrawElements
.
When
glDrawElements
is called, it uses
count
sequential elements from an
enabled array, starting at
indices
to construct a sequence of
geometric primitives.
mode
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.
Vertex attributes that are modified by
glDrawElements
have an
unspecified value after
glDrawElements
returns. Attributes that aren't
modified maintain their previous values.
Notes
GL_LINE_STRIP_ADJACENCY
,
GL_LINES_ADJACENCY
,
GL_TRIANGLE_STRIP_ADJACENCY
and
GL_TRIANGLES_ADJACENCY
are available only if the GL version is 3.2 or greater.
Errors
GL_INVALID_ENUM
is generated if
mode
is not an accepted value.
GL_INVALID_VALUE
is generated if
count
is negative.
GL_INVALID_OPERATION
is generated if a geometry shader is active and
mode
is incompatible with the input primitive type of the geometry shader in the currently installed program object.
GL_INVALID_OPERATION
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.
Copyright
Copyright
1991-2006
Silicon Graphics, Inc. This document is licensed under the SGI
Free Software B License. For details, see
http://oss.sgi.com/projects/FreeB/
.
Sample Code References
The following code samples have been found which appear to reference the functions described here. Take care that the code may be old, broken or not even use PyOpenGL.
glDrawElements