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point sprites and texture matrices

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if I were to apply a rotational texture matrix to a point sprite, would the graphic the point sprite generates be rotated? and on the subject of pointsprites what exactly do these three valuse do exactly? : D3DRS_POINTSCALE_A, D3DRS_POINTSCALE_B, D3DRS_POINTSCALE_C I have them set at 1.0, 0.9 and 0.8 respectavely and my sprites seem way to small. Bobboau, bringing you products that work... in theory

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I don''t know about the texture matrices... but I would have taken the whole 2 minutes it takes to modify a sample to test it. That way I''d have an accurate answer in 2 minutes instead of waiting a day or two for the people on the forum to either test it for me, or pick an answer at random and present it as fact... but that''s just me.

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yes but maybe you''d be doing something wrong and you wanted to get an answer from someone who knows weather or not you sould be waisting your time trying.

Bobboau, bringing you products that work... in theory

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Ok, good point. I still don''t know, but I have "an educated guess".

Point sprites are created from a single vertex, and are converted into a quad with the UVs set to (0,0) (0,1) (1,0) (1,1), as it says in the SDK page I mentioned above.

The question is whether texture transforms can affect those UVs, and my guess is no.

A vertex shader can transform points used in point sprites, and they output a single point with oPts set to the size of the point. But the vertex shader is also the section of the pipeline that is responsible for texture transformations. Since the output of this part of the pipeline is a single vertex, I can''t see how texture transforms would work.

It''s possible that it works in the fixed pipeline, but that would be a signifcant difference between fixed and programmable behaviour, thus I guess no.

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