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 09-03-2004, 10:16 AM #1 The_Nerd Member   Registered: Aug 2002 Distribution: Debian Posts: 540 Rep: OpenGL texture matrix rotation Ok, I have the code: Code: ```glMatrixMode(GL_TEXTURE); glLoadIdentity(); glRotate(X, 1,0,0); glRotate(Y, 0,1,0); glMatrixMode(GL_MODELVIEW);``` My problem is that my texture doesn't rotate the way I want it too. This is because texture coords are in the range (0-1), and since glRotatef rotates around 0, then I get my texture rotated off one corner of my polygon. How do I fix this?
 09-03-2004, 10:53 AM #2 The_Nerd Member   Registered: Aug 2002 Distribution: Debian Posts: 540 Original Poster Rep: Never mind. I figured it out. Just have to do a glTranslatef(0.5, 0.5, 0.5); before and a glTranslatef(-0.5, -0.5, -0.5); after.
 09-03-2004, 11:07 AM #3 kev82 Senior Member   Registered: Apr 2003 Location: Lancaster, England Distribution: Debian Etch, OS X 10.4 Posts: 1,263 Rep: I REALLY need to start refreshing before i post hopefully we're talking about 2d textures cos i dont know anything 3d textures. so we have our texture coordinates (a, b, c, d) i assume that your not trying freaky perspectuve effects so d=1 and c is irrelevant. i am quite confused as to what effect your trying to achieve by rotating about the x and y axes, surely if you want to spin the texture you want to rotate it about the Z axis?? anyway, if you want to spin the texture about its center then first we have to move to the the center of the texture, then rotate, then move back, just like we would normally glPushAttrib(GL_TRANSFORM_BIT); glMatrixMode(GL_TEXTURE); glLoadIdentity(); glTranslatef(0.5, 0.5, 0); glRotatef(angle, 0, 0, 1); glTranslatef(-0.5, -0.5, 0); glPopAttrib(); make sure all required coordinates lie in the texture or you might include garbage data Last edited by kev82; 09-03-2004 at 11:08 AM.
 09-03-2004, 02:11 PM #4 The_Nerd Member   Registered: Aug 2002 Distribution: Debian Posts: 540 Original Poster Rep: Thanks. Sorry I made you reply when I didn't need you too. Appreciate it though.

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