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reubenhawkins
07-01-2002, 06:56 PM
Iím experimenting with Vertex Shaders on a RADEON 8500. When I define my own shader to simply do what HW T&L does with no lighting, I get about 150 FPS when T&L gets over 1000. However, I modified ATIís Vertex Shader demo to print the FPS and it consistently gets over 800 FPS even when doing lighting and the code is almost the exact same as mine. What am I missing? Is there some non-default library or something else that I donít know about??? I appreciate your inputsÖ

NitroGL
07-01-2002, 07:11 PM
What's the code for the shader?

All I have in my shader is (ok, not all, but you get the idea http://www.opengl.org/discussion_boards/ubb/smile.gif):



glShaderOp2EXT(GL_OP_MULTIPLY_MATRIX_EXT, EyeVertex, ModelView, Vertex);
glShaderOp2EXT(GL_OP_MULTIPLY_MATRIX_EXT, GL_OUTPUT_VERTEX_EXT, Projection, EyeVertex);

glShaderOp1EXT(GL_OP_MOV_EXT, GL_OUTPUT_COLOR0_EXT, Color);

and I get about 500FPS on a quad made up of 1152 triangles (drawn using glDrawElements).

[This message has been edited by NitroGL (edited 07-01-2002).]

knackered
07-01-2002, 10:52 PM
Urg! The sooner ATI come up with a Cg compiler profile for their stuff, the better.... http://www.opengl.org/discussion_boards/ubb/wink.gif

reubenhawkins
07-02-2002, 04:38 AM
well hmmmmmm... I don't know what the deal is but I created a new project from scratch and it seems to run fine at ~850 fps... Try rendering a teapot with a vertex shader if you don't mind and tell me you FPS and specs. Thanks.