Difference between revisions of "GLAPI/glMultiDrawElements"

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: Specifies what kind of primitives to render. Symbolic constants {{enum|GL_POINTS}}, {{enum|GL_LINE_STRIP}}, {{enum|GL_LINE_LOOP}}, {{enum|GL_LINES}}, {{enum|GL_LINE_STRIP_ADJACENCY}}, {{enum|GL_LINES_ADJACENCY}}, {{enum|GL_TRIANGLE_STRIP}}, {{enum|GL_TRIANGLE_FAN}}, {{enum|GL_TRIANGLES}}, {{enum|GL_TRIANGLE_STRIP_ADJACENCY}}, {{enum|GL_TRIANGLES_ADJACENCY}} and {{enum|GL_PATCHES}} are accepted.
 
: Specifies what kind of primitives to render. Symbolic constants {{enum|GL_POINTS}}, {{enum|GL_LINE_STRIP}}, {{enum|GL_LINE_LOOP}}, {{enum|GL_LINES}}, {{enum|GL_LINE_STRIP_ADJACENCY}}, {{enum|GL_LINES_ADJACENCY}}, {{enum|GL_TRIANGLE_STRIP}}, {{enum|GL_TRIANGLE_FAN}}, {{enum|GL_TRIANGLES}}, {{enum|GL_TRIANGLE_STRIP_ADJACENCY}}, {{enum|GL_TRIANGLES_ADJACENCY}} and {{enum|GL_PATCHES}} are accepted.
 
; count
 
; count
: Points to an array of the elements counts.
+
: Points to an array of {{param|drawcount}} values, each value representing the number of indices to draw.
 
; type
 
; type
 
: Specifies the type of the values in {{param|indices}}. Must be one of {{enum|GL_UNSIGNED_BYTE}}, {{enum|GL_UNSIGNED_SHORT}}, or {{enum|GL_UNSIGNED_INT}}.
 
: Specifies the type of the values in {{param|indices}}. Must be one of {{enum|GL_UNSIGNED_BYTE}}, {{enum|GL_UNSIGNED_SHORT}}, or {{enum|GL_UNSIGNED_INT}}.
 
; indices
 
; indices
: Specifies a pointer to the location where the indices are stored.
+
: Points to an array of {{param|drawcount}} values, where each value is a byte offset (cast to a pointer type) into the buffer bound to {{enum|GL_ELEMENT_ARRAY_BUFFER}} to start reading indices from.
 
; drawcount
 
; drawcount
 
: Specifies the size of the {{param|count}} and {{param|indices}} arrays.
 
: Specifies the size of the {{param|count}} and {{param|indices}} arrays.

Latest revision as of 01:23, 31 July 2013

glMultiDrawElements
Core in version 4.5
Core since version 1.4

glMultiDrawElements: render multiple sets of primitives by specifying indices of array data elements

Function Definition

 void glMultiDrawElements(GLenum mode​, const GLsizei * count​, GLenum type​, const GLvoid * const * indices​, GLsizei drawcount​);
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.
count
Points to an array of drawcount​ values, each value representing the number of indices to draw.
type
Specifies the type of the values in indices​. Must be one of GL_UNSIGNED_BYTE, GL_UNSIGNED_SHORT, or GL_UNSIGNED_INT.
indices
Points to an array of drawcount​ values, where each value is a byte offset (cast to a pointer type) into the buffer bound to GL_ELEMENT_ARRAY_BUFFER to start reading indices from.
drawcount
Specifies the size of the count​ and indices​ arrays.

Description

glMultiDrawElements specifies multiple sets of geometric primitives with very few subroutine calls. Instead of calling a GL function to pass each individual vertex, normal, texture coordinate, edge flag, or color, you can prespecify separate arrays of vertices, normals, and so on, and use them to construct a sequence of primitives with a single call to glMultiDrawElements.

glMultiDrawElements is identical in operation to glDrawElements except that drawcount​ separate lists of elements are specified.

Vertex attributes that are modified by glMultiDrawElements have an unspecified value after glMultiDrawElements returns. Attributes that aren't modified maintain their previous values.

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 drawcount​ is negative.

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

glBindVertexArray, glDrawElements, glDrawElementsBaseVertex, glDrawElementsIndirect, glDrawElementsInstanced, glDrawElementsInstancedBaseInstance, glDrawElementsInstancedBaseVertex, glDrawElementsInstancedBaseVertexBaseInstance, glDrawRangeElements, glDrawRangeElementsBaseVertex, glMultiDrawArrays, glMultiDrawElementsBaseVertex, glMultiDrawElementsIndirect

Copyright

Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2010-2013 Khronos Group. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.