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Trapezoids and textures
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Trapezoids and textures

Is there any way to get around this rendering artifact in GL?
When I draw a quad that is a trapezoid and place a texture on it the
texture gets minified in strange ways.
Apparently the GL pipeline is breaking up the trapezoid into triangles
and then reapplying the texture.
This looks really bad. Is this there a way around this?
here is what it looks like....
http://viz.tamu.edu/students/mistrot/GL/trapezoid_artifact.jpg

Here is how I am drawing the Quad
when topright or topleft are less <-1 and >1 respectively you get the
artifact....
parallelograms don't seem to have this problem.

glBindTexture(GL_TEXTURE_2D, texName[0]);
glBegin(GL_QUADS);
glTexCoord2f(0.0, 0.0); glVertex3f(-1.0, -1.0, 0.0);
glTexCoord2f(0.0, 1.0); glVertex3f(topleft, 01.0, 0.0);
glTexCoord2f(1.0, 1.0); glVertex3f(topright, 01.0, 0.0);
glTexCoord2f(1.0, 0.0); glVertex3f(1.0, -1.0, 0.0);
glEnd();
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