Name

glMultiDrawArrays — render multiple sets of primitives from array data

C Specification

void glMultiDrawArrays(GLenum mode,
 GLint * first,
 GLsizei * count,
 GLsizei primcount);
 

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.

first

Points to an array of starting indices in the enabled arrays.

count

Points to an array of the number of indices to be rendered.

primcount

Specifies the size of the first and count

Description

glMultiDrawArrays specifies multiple sets of geometric primitives with very few subroutine calls. Instead of calling a GL procedure to pass each individual vertex, normal, texture coordinate, edge flag, or color, you can prespecify separate arrays of vertices, normals, and colors and use them to construct a sequence of primitives with a single call to glMultiDrawArrays.

glMultiDrawArrays behaves identically to glDrawArrays except that primcount separate ranges of elements are specified instead.

When glMultiDrawArrays is called, it uses count sequential elements from each enabled array to construct a sequence of geometric primitives, beginning with element first. mode specifies what kind of primitives are constructed, and how the array elements construct those primitives. If GL_VERTEX_ARRAY is not enabled, no geometric primitives are generated.

Vertex attributes that are modified by glMultiDrawArrays have an unspecified value after glMultiDrawArrays returns. For example, if GL_COLOR_ARRAY is enabled, the value of the current color is undefined after glMultiDrawArrays executes. Attributes that aren't modified remain well defined.

Notes

glMultiDrawArrays is available only if the GL version is 1.4 or greater.

glMultiDrawArrays is included in display lists. If glMultiDrawArrays 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 primcount is negative.

GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to an enabled array and the buffer object's data store is currently mapped.

GL_INVALID_OPERATION is generated if glMultiDrawArrays is executed between the execution of glBegin and the corresponding glEnd.

See Also

glArrayElement, glColorPointer, glDrawElements, glDrawRangeElements, glEdgeFlagPointer, glFogCoordPointer, glGetPointerv, glIndexPointer, glInterleavedArrays, glNormalPointer, glSecondaryColorPointer, glTexCoordPointer, glVertexPointer

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.