1991-2006
Silicon Graphics, Inc.
glDrawElements
3G
glDrawElements
render primitives from array data
C Specification
void glDrawElements
GLenum mode
GLsizei count
GLenum type
const GLvoid * indices
Parameters
mode
Specifies what kind of primitives to render.
Symbolic constants
GL_POINTS,
GL_LINE_STRIP,
GL_LINE_LOOP,
GL_LINES,
GL_TRIANGLE_STRIP,
GL_TRIANGLE_FAN,
GL_TRIANGLES,
GL_QUAD_STRIP,
GL_QUADS,
and GL_POLYGON 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. If
GL_VERTEX_ARRAY is not enabled, no geometric primitives are
constructed.
Vertex attributes that are modified by glDrawElements have an
unspecified value after glDrawElements returns. For example, if
GL_COLOR_ARRAY is enabled, the value of the current color is
undefined after glDrawElements executes. Attributes that aren't
modified maintain their previous values.
Notes
glDrawElements is available only if the GL version is 1.1 or greater.
glDrawElements is included in display lists. If glDrawElements 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.
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 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.
GL_INVALID_OPERATION is generated if glDrawElements is executed between
the execution of glBegin and the corresponding glEnd.
See Also
glArrayElement,
glColorPointer,
glDrawArrays,
glDrawRangeElements,
glEdgeFlagPointer,
glFogCoordPointer,
glGetPointerv,
glIndexPointer,
glInterleavedArrays,
glNormalPointer,
glSecondaryColorPointer,
glTexCoordPointer,
glVertexPointer
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/.