glDrawElementsBaseVertex

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Render primitives from array data with a per-element offset.

C Specification[edit]

void glDrawElementsBaseVertex( GLenum mode, GLsizei count, GLenum type, void * indices, GLint basevertex );


Parameters[edit]

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_LINES_ADJACENCY , GL_LINE_STRIP_ADJACENCY , GL_TRIANGLES_ADJACENCY , GL_TRIANGLE_STRIP_ADJACENCY and GL_PATCHES 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 pointer to the location where the indices are stored.
basevertex - Specifies a constant that should be added to each element of indices when chosing elements from the enabled vertex arrays.


Description[edit]

 glDrawElementsBaseVertex behaves identically to glDrawElements except that theith element transferred by the corresponding draw call will be taken from element indices [i] + basevertex of each enabled array. If the resulting value is larger than the maximum value representable by type , it is as if the calculation were upconverted to 32-bit unsigned integers (with wrapping on overflow conditions). The operation is undefined if the sum would be negative.


Notes[edit]

 glDrawElementsBaseVertex is only supported if the GL version is 3.2 or greater, or if theARB_draw_elements_base_vertexextension is supported.


Errors[edit]

 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 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 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.


Version Support[edit]

 glDrawElementsBaseVertex  3.2+

See Also[edit]

 glDrawElements , glDrawRangeElements , glDrawRangeElementsBaseVertex , glDrawElementsInstanced , glDrawElementsInstancedBaseVertex 


Copyright[edit]

Copyright© 2010-2014 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/.