GLDRAWELEMENTS(3G)GLDRAWELEMENTS(3G)NAMEglDrawElements - render primitives from array data
C SPECIFICATION
void glDrawElements( GLenum mode,
GLsizei count,
GLenum type,
const GLvoid *indices )
delim $$
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.
DESCRIPTIONglDrawElements 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.
NOTESglDrawElements 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 glDrawElements is executed between
the execution of glBegin and the corresponding glEnd.
SEE ALSOglArrayElement(3G), glColorPointer(3G), glDrawArrays(3G),
glDrawRangeElements(3G), glEdgeFlagPointer(3G), glGetPointerv(3G),
glIndexPointer(3G), glInterleavedArrays(3G), glNormalPointer(3G),
glTexCoordPointer(3G), glVertexPointer(3G)
March 1, 2011
