GLDRAWARRAYSINDIRECT(3G)

    .SH "NAME" glDrawArraysIndirect - render primitives from array data, taking parameters from memory
    .SH "C SPECIFICATION"

            .HP u void glDrawArraysIndirect(GLenum mode, const void *indirect);

    .SH "PARAMETERS"

        .PP 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.

            .RE
            .PP indirect

                        Specifies the address of a structure containing the draw parameters.

                .RE

            .SH "DESCRIPTION"
                .PP glDrawArraysIndirect specifies multiple geometric primitives with very few subroutine calls. glDrawArraysIndirect behaves similarly to glDrawArraysInstanced(), except that the parameters to glDrawArraysInstanced() are stored in memory at the address given by indirect.
                .PP 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);

                .PP 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.
                .PP In contrast to glDrawArraysInstanced(), the first member of the parameter structure is unsigned, and out-of-range indices do not generate an error.
                .PP Vertex attributes that are modified by glDrawArraysIndirect have an unspecified value after glDrawArraysIndirect returns. Attributes that aren't modified remain well defined.

            .SH "NOTES"
                .PP The reserved member of the DrawArraysIndirectCommand structure should be set to zero. Behavior is undefined if it is non-zero.
                .PP GL_LINE_STRIP_ADJACENCY, GL_LINES_ADJACENCY, GL_TRIANGLE_STRIP_ADJACENCY, GL_TRIANGLES_ADJACENCY and GL_PATCHES are available only if the GL ES version is 3.2 or greater.

            .SH "ERRORS"
                .PP GL_INVALID_ENUM is generated if mode is not an accepted value.
                .PP 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.
                .PP 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.

            .SH "API VERSION SUPPORT"

                .TS allbox tab(:); l l l l l. T{ glDrawArraysIndirect T}:T{ T}:T{ T}:T{ T}:T{ T}

            .SH "SEE ALSO"
                .PP glDrawArrays(), glDrawArraysInstanced(), glDrawElements(), glDrawRangeElements(),

            .SH "COPYRIGHT"
                .PP Copyright © 2010-2015 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/.

COPYRIGHT
Copyright © 2010-2015 Khronos Group.