glDrawElements(3G) OpenGL Reference glDrawElements(3G)
NAME
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
GLPOINTS, GLLINESTRIP, GLLINELOOP, GLLINES,
GLTRIANGLESTRIP, GLTRIANGLEFAN, GLTRIANGLES, GLQUADSTRIP,
GLQUADS, and GLPOLYGON are accepted.
count Specifies the number of elements to be rendered.
type Specifies the type of the values in indices. Must be one of
GLUNSIGNEDBYTE, GLUNSIGNEDSHORT, or GLUNSIGNEDINT.
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 vertexes, 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 GLVERTEXARRAY 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 GLCOLORARRAY is
enabled, the value of the current color is undefined after glDrawElements
executes. Attributes that aren't modified remain well defined.
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
Page 1
glDrawElements(3G) OpenGL Reference glDrawElements(3G)
display lists when the lists are created, not when the lists are
executed.
ERRORS
GLINVALIDENUM is generated if mode is not an accepted value.
GLINVALIDVALUE is generated if count is negative.
GLINVALIDOPERATION is generated if glDrawElements is executed between
the execution of glBegin and the corresponding glEnd.
SEE ALSO
glArrayElement, glColorPointer, glDrawArrays, glEdgeFlagPointer,
glGetPointerv, glIndexPointer, glInterleavedArrays, glNormalPointer,
glTexCoordPointer, glVertexPointer
Page 2