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fallout
10-17-2004, 12:31 PM
lets say I have a function called drawcube()
that draws a cube about the origin.
Then I translate, rotate, etc that cube. Something like:

glPushMatrix();
glRotatef(32,0,1,0);
glTranslatef(10,-20,1);
drawcube()
glPopMatrix();

Is there a way I can get the coordinates of the cube?
Its easy to keep track of coordinates with translations, but I'm mostly confused on the getting the coordinates after rotations.

Thanks

-NiCo-
10-17-2004, 02:34 PM
You can retrieve the modelviewmatrix right before your call to drawcube.

GLfloat mm[16];
glGetFLoatv(GL_MODELVIEW_MATRIX,&mm[0]);

and use that matrix to transform the original coordinates.

Note that in OpenGL matrices are stored in column major order.

Greetz,

Nico