GLDRAWELEMENTSINSTAN(3G)        [FIXME: manual]       GLDRAWELEMENTSINSTAN(3G)

NAME
       glDrawElementsInstanced - draw multiple instances of a set of elements

C SPECIFICATION
       void glDrawElementsInstanced(GLenum mode, GLsizei count, GLenum type,
                                    const void * indices,
                                    GLsizei instancecount);

PARAMETERS
       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
           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.

       instancecount
           Specifies the number of instances of the specified range of indices
           to be rendered.

DESCRIPTION
       glDrawElementsInstanced behaves identically to glDrawElements() except
       that instancecount instances of the set of elements are executed and
       the value of the internal counter instanceID advances for each
       iteration.  instanceID is an internal 32-bit integer counter that may
       be read by a vertex shader as gl_InstanceID.

       glDrawElementsInstanced has the same effect as:

               if (mode, count, or type is invalid )
                   generate appropriate error
               else {
                   for (int i = 0; i < instancecount ; i++) {
                       instanceID = i;
                       glDrawElements(mode, count, type, indices);
                   }
                   instanceID = 0;
               }


NOTES
       glDrawElementsInstanced is available only if the GL version is 3.1 or
       greater.

       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 one of GL_POINTS,
       GL_LINE_STRIP, GL_LINE_LOOP, GL_LINES, GL_TRIANGLE_STRIP,
       GL_TRIANGLE_FAN, or GL_TRIANGLES.

       GL_INVALID_VALUE is generated if count or instancecount 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 and the buffer object's data store is
       currently mapped.

VERSION SUPPORT

       +------------------------+-----------------------------------------------------------------------+
       |                        |                            OpenGL Version                             |
       +------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |Function / Feature Name | 2.0 | 2.1 | 3.0 | 3.1 | 3.2 | 3.3 | 4.0 | 4.1 | 4.2 | 4.3 | 4.4 | 4.5 |
       +------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
       |glDrawElementsInstanced |  -  |  -  |  -  | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> | <?> |
       +------------------------+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

SEE ALSO
       glDrawElements(), glDrawArraysInstanced()

COPYRIGHT
       Copyright (C) 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.  https://opencontent.org/openpub/.

COPYRIGHT
       Copyright (C) 2010-2014 Khronos Group

[FIXME: source]                   10/20/2024          GLDRAWELEMENTSINSTAN(3G)