glDrawElements — render primitives from array data
void glDrawElements( | GLenum mode, |
GLsizei count, | |
GLenum type, | |
const void * indices) ; |
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
, and
GL_TRIANGLES
are accepted.
count
Specifies the number of elements to be rendered.
type
Specifies the type of the values in indices
. Must be
GL_UNSIGNED_BYTE
or GL_UNSIGNED_SHORT
.
indices
Specifies a pointer to the location where the indices are stored.
glDrawElements
specifies multiple geometric primitives
with very few subroutine calls. Instead of calling a GL function
to pass each vertex attribute, you can use
glVertexAttribPointer
to prespecify separate arrays of vertex attributes 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.
To enable and disable a generic vertex attribute array, call glEnableVertexAttribArray and glDisableVertexAttribArray.
If the current program object, as set by glUseProgram, is invalid, rendering results are undefined. However, no error is generated for this case.
GL_INVALID_ENUM
is generated if mode
is not an accepted value.
GL_INVALID_ENUM
is generated if type
is not
GL_UNSIGNED_BYTE
or GL_UNSIGNED_SHORT
.
GL_INVALID_VALUE
is generated if count
is negative.
GL_INVALID_FRAMEBUFFER_OPERATION
is generated if
the currently bound framebuffer is not framebuffer complete (i.e. the
return value from glCheckFramebufferStatus
is not GL_FRAMEBUFFER_COMPLETE
).
glCheckFramebufferStatus, glDisableVertexAttribArray, glDrawArrays, glEnableVertexAttribArray, glUseProgram, glVertexAttribPointer
Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see https://khronos.org/registry/OpenGL-Refpages/LICENSES/LicenseRef-FreeB.txt.