%mathent; ]> 2010-2014 Khronos Group. glDrawArraysIndirect 3G glDrawArraysIndirect render primitives from array data, taking parameters from memory C Specification void glDrawArraysIndirect GLenum mode const void *indirect 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. indirect Specifies the address of a structure containing the draw parameters. Description glDrawArraysIndirect specifies multiple geometric primitives with very few subroutine calls. glDrawArraysIndirect behaves similarly to glDrawArraysInstanced, execept that the parameters to glDrawArraysInstanced are stored in memory at the address given by indirect. The parameters addressed by indirect are packed into a structure that takes the form (in C): typedef struct { uint count; uint primCount; uint first; uint reserved; } DrawArraysIndirectCommand; const DrawArraysIndirectCommand *cmd = (const DrawArraysIndirectCommand *)indirect; glDrawArraysInstanced(mode, cmd->first, cmd->count, cmd->primCount); If a buffer is bound to the GL_DRAW_INDIRECT_BUFFER binding at the time of a call to glDrawArraysIndirect, indirect is interpreted as an offset, in basic machine units, into that buffer and the parameter data is read from the buffer rather than from client memory. In contrast to glDrawArraysInstanced, the first member of the parameter structure is unsigned, and out-of-range indices do not generate an error. Vertex attributes that are modified by glDrawArraysIndirect have an unspecified value after glDrawArraysIndirect returns. Attributes that aren't modified remain well defined. Notes The reserved member of the DrawArraysIndirectCommand structure should be set to zero. Behavior is undefined if it is non-zero. Errors GL_INVALID_ENUM is generated if mode is not an accepted value. GL_INVALID_OPERATION is generated if a non-zero buffer object name is bound to an enabled array or to the GL_DRAW_INDIRECT_BUFFER binding and the buffer object's data store is currently mapped. API Version Support glDrawArraysIndirect See Also glDrawArrays, glDrawArraysInstanced, glDrawElements, glDrawRangeElements, Copyright 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/.