glDrawElements: render primitives from array data.
C Specification |
const GLvoid *indices)
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.
- Specifies what kind of primitives to render. Symbolic constants
GL_QUADS, and GL_POLYGON are accepted.
- Specifies the number of elements to be rendered.
- Specifies the type of the values in indices. Must be one
of GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT, or
- Specifies a pointer to the location where the indices are stored.
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 remain well defined.
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.
- GL_INVALID_ENUM is generated if mode is
not an accepted value.
- GL_INVALID_VALUE is generated if count is
- GL_INVALID_OPERATION is generated if glDrawElements is executed between
the execution of glBegin and the