Manpages OpenGL - glDrawElementsBaseVertex

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Name

glDrawElementsBaseVertex — render primitives from array data with a per-element offset

C Specification

`void glDrawElementsBaseVertex(`	GLenum	`mode`,
	GLsizei	`count`,
	GLenum	`type`,
	GLvoid *	`indices`,
	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, 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 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

glDrawElementsBaseVertex behaves identically to glDrawElements 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

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

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 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.