glDrawElements - OpenGL ES 3.1 Reference Pages

## 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` and `GL_TRIANGLES` 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 byte offset (cast to a pointer type) into the buffer bound to `GL_ELEMENT_ARRAY_BUFFER` to start reading indices from. If no buffer is bound, specifies a pointer to the location where the indices are stored.

## Description

`glDrawElements` specifies multiple geometric primitives with very few subroutine calls. It is possible to prespecify separate arrays of attributes 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.

To enable and disable a generic vertex attribute array, call glEnableVertexAttribArray and glDisableVertexAttribArray.

If an array corresponding to a generic attribute required by a vertex shader is not enabled, then the corresponding element is taken from the current generic attribute state.

## 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 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_FRAMEBUFFER_OPERATION` is generated if the currently bound framebuffer is not framebuffer complete (i.e. the return value from glCheckFramebufferStatus is not `GL_FRAMEBUFFER_COMPLETE`).

`GL_INVALID_OPERATION` is generated if transform feedback is active and not paused.

## API Version Support

| OpenGL ES API Version
--- | ---
Function Name | 2.0 | 3.0 | 3.1
glDrawElements | ✔ | ✔ | ✔

## See Also

glCheckFramebufferStatus, glDisableVertexAttribArray, glDrawArrays, glDrawArraysInstanced, glDrawElementsInstanced, glDrawRangeElements, glEnableVertexAttribArray

## Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2014 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.