1991-2006
Silicon Graphics, Inc.
glDrawRangeElements
3G

# glDrawRangeElements

render primitives from array data

## C Specification

                    void glDrawRangeElements
                    GLenum mode
                    GLuint start
                    GLuint end
                    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.

`start`

  Specifies the minimum array index contained in `indices`.

`end`

  Specifies the maximum array index contained in `indices`.

`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

`glDrawRangeElements` is a restricted form of glDrawElements. `mode`, `start`, `end`, and `count` match the corresponding arguments to glDrawElements, with the additional constraint that all values in the arrays `count` must lie between `start` and `end`, inclusive.

Implementations denote recommended maximum amounts of vertex and index data, which may be queried by calling glGet with argument `GL_MAX_ELEMENTS_VERTICES` and `GL_MAX_ELEMENTS_INDICES`. If end - start + 1 is greater than the value of `GL_MAX_ELEMENTS_VERTICES`, or if `count` is greater than the value of `GL_MAX_ELEMENTS_INDICES`, then the call may operate at reduced performance. There is no requirement that all vertices in the range start end be referenced. However, the implementation may partially process unused vertices, reducing performance from what could be achieved with an optimal index set.

When `glDrawRangeElements` is called, it uses `count` sequential elements from an enabled array, starting at `start` 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 `glDrawRangeElements` have an unspecified value after `glDrawRangeElements` returns. For example, if `GL_COLOR_ARRAY` is enabled, the value of the current color is undefined after `glDrawRangeElements` executes. Attributes that aren't modified maintain their previous values.

## Notes

`glDrawRangeElements` is available only if the GL version is 1.2 or greater.

`glDrawRangeElements` is included in display lists. If `glDrawRangeElements` 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

It is an error for indices to lie outside the range start end , but implementations may not check for this situation. Such indices cause implementation-dependent behavior.

`GL_INVALID_ENUM` is generated if `mode` is not an accepted value.

`GL_INVALID_VALUE` is generated if `count` is negative.

`GL_INVALID_VALUE` is generated if end < start .

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

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

## Associated Gets

glGet with argument `GL_MAX_ELEMENTS_VERTICES`

glGet with argument `GL_MAX_ELEMENTS_INDICES`

## See Also

glArrayElement, glColorPointer, glDrawArrays, glDrawElements, glEdgeFlagPointer, 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/.