My geometry shader has no effect when the input primitive is GL_POINTS. I have to feed the geometry shader with one GL_LINES primitive, repeating the first vertex.
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I have the latest drivers are installed
ATI Mobility Radeon HD5470
Windows 7 x64
Catalyst Version: 10.8
Driver Packaging Version: 8.762.100803a-103697C-ATI
OpenGL Version: 22.214.171.12451