GL_OES_stencil_wrap#
Supported Hardware#
Series5, Series5XT, Series6, Series6XE, Series6XT
Valid APIs#
OpenGL ES 1.x
Description#
Core OpenGL ES 1.0 stencil buffers require that when a value is incremented to the maximum value or decreased to the minimum, further operations will clamp that value. However, a number of algorithms use this buffer as a counter, calculating the difference between the total number of increments and the total number of decrements. This extension adds two new stencil operations: INCR_WRAP and DECR_WRAP. These allow the value to wrap round when the value changes and give more flexibility to the stencil buffer.
Note#
This extension is part of the OpenGL ES 1.x Extension Pack Specification and is core functionality in OpenGL ES 2.0 and 3.0.
Registry Link#
http://www.khronos.org/registry/gles/extensions/OES/OES_stencil_wrap.txt
Example#
// Change the stencil operations to decrease and wrap when failing the depth or stencil test,
// and increase and wrap when succeeding
glStencilOp(GL_DECR_WRAP, GL_DECR_WRAP, GL_INCR_WRAP);