GLAPI/glDrawTransformFeedback

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glDrawTransformFeedback
Core in version 4.4
Core since version 4.0
Core ARB extension ARB_transform_feedback2

glDrawTransformFeedback: render primitives using a count derived from a transform feedback object

Function Definition

 void glDrawTransformFeedback(GLenum mode​, GLuint id​);
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.
id
Specifies the name of a transform feedback object from which to retrieve a primitive count.

Description

glDrawTransformFeedback draws primitives of a type specified by mode​ using a count retrieved from the transform feedback specified by id​. Calling glDrawTransformFeedback is equivalent to calling glDrawArrays with mode​ as specified, first​ set to zero, and count​ set to the number of vertices captured on vertex stream zero the last time transform feedback was active on the transform feedback object named by id​.

Errors

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

GL_INVALID_VALUE​ is generated if id​ is not the name of a transform feedback object.

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.

GL_INVALID_OPERATION​ is generated if mode​ is GL_PATCHES​ and no tessellation control shader is active.

GL_INVALID_OPERATION​ is generated if glEndTransformFeedback has never been called while the transform feedback object named by id​ was bound.

See Also

glBindVertexArray, glDrawArrays, glDrawTransformFeedbackInstanced, glDrawTransformFeedbackStream, glDrawTransformFeedbackStreamInstanced

Copyright

Copyright © 2010 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.