2010
Khronos Group
glDrawElementsInstancedBaseVertex
3G
glDrawElementsInstancedBaseVertex
render multiple instances of a set of primitives from array data with a per-element offset
C Specification
void glDrawElementsInstancedBaseVertex
GLenum mode
GLsizei count
GLenum type
GLvoid *indices
GLsizei primcount
GLint basevertex
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_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.
primcount
Specifies the number of instances of the indexed geometry that should be drawn.
basevertex
Specifies a constant that should be added to each element of indices
when chosing elements from the enabled vertex arrays.
Description
glDrawElementsInstancedBaseVertex behaves identically to
glDrawElementsInstanced except that the ith 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
glDrawElementsInstancedBaseVertex is only supported 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 or primcount 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.
See Also
glDrawElements,
glDrawRangeElements,
glDrawRangeElementsBaseVertex,
glDrawElementsInstanced,
glDrawElementsInstancedBaseVertex
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/.