GLAPI/glDrawArrays

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glDrawArrays
Core in version 4.4
Core since version 1.1

glDrawArrays: render primitives from array data

Function Definition

 void glDrawArrays(GLenum mode​, GLint first​, GLsizei count​);
mode
Specifies what kind of primitives to render. Symbolic constants GL_POINTS​, GL_LINE_STRIP​, GL_LINE_LOOP​, GL_LINES​, GL_LINE_STRIP_ADJACENCY​, GL_LINES_ADJACENCY​, GL_TRIANGLE_STRIP​, GL_TRIANGLE_FAN​, GL_TRIANGLES​, GL_TRIANGLE_STRIP_ADJACENCY​, GL_TRIANGLES_ADJACENCY​ and GL_PATCHES​ are accepted.
first
Specifies the starting index in the enabled arrays.
count
Specifies the number of indices to be rendered.

Description

glDrawArrays specifies multiple 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 glDrawArrays.

When glDrawArrays 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.

Vertex attributes that are modified by glDrawArrays have an unspecified value after glDrawArrays returns. Attributes that aren't modified remain well defined.

Notes

GL_LINE_STRIP_ADJACENCY​, GL_LINES_ADJACENCY​, GL_TRIANGLE_STRIP_ADJACENCY​ and GL_TRIANGLES_ADJACENCY​ are available only if the GL version is 3.2 or greater.

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 and the buffer object's data store is currently mapped.

GL_INVALID_OPERATION​ is generated if a geometry shader is active and mode​ is incompatible with the input primitive type of the geometry shader in the currently installed program object.

See Also

glBindVertexArray, glDrawArraysIndirect, glDrawArraysInstanced, glDrawArraysInstancedBaseInstance, glMultiDrawArrays, glMultiDrawArraysIndirect

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/.