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GLDRAWELEMENTS(3G)                                                                        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 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 glDrawElements is executed between the execution of glBegin and
       the corresponding glEnd.

SEE ALSO
       glArrayElement(3G), glColorPointer(3G), glDrawArrays(3G), glDrawRangeElements(3G), glEdgeFlagPointer(3G),  glGetPointerv(3G),
       glIndexPointer(3G), glInterleavedArrays(3G), glNormalPointer(3G), glTexCoordPointer(3G), glVertexPointer(3G)





                                                                                          GLDRAWELEMENTS(3G)