OpenGL.GL.SGIS.multisample

OpenGL extension SGIS.multisample

This module customises the behaviour of the OpenGL.raw.GL.SGIS.multisample to provide a more Python-friendly API

Overview (from the spec)

This extension provides a mechanism to antialias all GL primitives: points, lines, polygons, bitmaps, and images. The technique is to sample all primitives multiple times at each pixel. The color sample values are resolved to a single, displayable color each time a pixel is updated, so the antialiasing appears to be automatic at the application level. Because each sample includes depth and stencil information, the depth and stencil functions perform equivalently to the single-sample mode.

An additional buffer, called the multisample buffer, is added to the framebuffer. Pixel sample values, including color, depth, and stencil values, are stored in this buffer. When the framebuffer includes a multisample buffer, it does not also include separate depth or stencil buffers, even if the multisample buffer does not store depth or stencil values. Color buffers (left/right, front/ back, and aux) do coexist with the multisample buffer, however.

Multisample antialiasing is most valuable for rendering polygons, because it requires no sorting for hidden surface elimination, and it correctly handles adjacent polygons, object silhouettes, and even intersecting polygons. If only points or lines are being rendered, the "smooth" antialiasing mechanism provided by the base GL may result in a higher quality image. This extension is designed to allow multisample and smooth antialiasing techniques to be alternated during the rendering of a single scene.

The official definition of this extension is available here: http://www.opengl.org/registry/specs/SGIS/multisample.txt