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# Why 4 Coords for a Quad?

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Well what i´ve been askin me for while now is, why do I have to give 4 Points to definate a Quad or Rect. 2 Points would be enough, you know now what I mean or? f.E upper left Point and the lower right. Take care Doc

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The reason is is that not all quadrilaterals are rectangles. If you want to make a rhombus, parallelogram, or trapezoid, two corners are insufficient to establish the dimensions of the quad. Using squares and rectangles, you''re right -- two is enough. But to be able to handle ALL quads, we must use all four, so we establish 4 points to every quad.

~ Dragonus

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if u working in 2d then AND ONLY then 2pionts are enough, but if u are working in 3d then u need 3points..because the squad could be rotated around the line wich is between point A and point B, so u need a third point to define the plane on wich the quad is

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