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'''OpenGL extension SGIX.vertex_preclip |
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This module customises the behaviour of the |
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OpenGL.raw.GL.SGIX.vertex_preclip to provide a more |
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Python-friendly API |
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Overview (from the spec) |
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Certain graphics subsystems are capable of performing fast |
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2D viewport or, in some cases, 3D volume "scissoring" operations |
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within some coordinate range much faster that the host CPU could |
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re-tesselate clipped primitives. |
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This extension introduces the notion of an extended rasterizable view |
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volume that is an expansion of the clip-space view volume. This volume |
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is the space within which a particular graphics system is much more |
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efficient at rejecting fragments that lie outside the view volume than |
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it is at performing strict view volume clipping. |
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Clip-checking can be turned on or off through the glEnable/glDisable |
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mechanism, and can be further controlled by using glHint. |
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The official definition of this extension is available here: |
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http://www.opengl.org/registry/specs/SGIX/vertex_preclip.txt |
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''' |
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from OpenGL import platform, constant, arrays |
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from OpenGL import extensions, wrapper |
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import ctypes |
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from OpenGL.raw.GL import _types, _glgets |
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from OpenGL.raw.GL.SGIX.vertex_preclip import * |
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from OpenGL.raw.GL.SGIX.vertex_preclip import _EXTENSION_NAME |
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def glInitVertexPreclipSGIX(): |
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'''Return boolean indicating whether this extension is available''' |
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from OpenGL import extensions |
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return extensions.hasGLExtension( _EXTENSION_NAME ) |
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