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BryceSummers

Why might clipping create more triangles?

aznshodan

it seems like there are two triangles on the top left after clipping instead of one. but I'm not sure how that happened.

Khryl

I thinks it's because when we clip a triangle, the remaining part can be quadrilateral. So we have to use two triangles to represent a quadrilateral, causing more triangles after clipping.

BryceSummers

@Khryl That is a good explanation of the phenomena. At the recitation yesterday Kayvon mentioned that up to around 6 triangles might be formed.

Can anybody search for the most degenerate case in terms of the number of triangles?

PandaX

@Khryl Good explanation! Thanks!

kayvonf

Question: Can someone list a few reasons why it is useful to perform clipping? We talked about this in some detail during "Pizza with Kayvon". (Hint: we talked about both performance reasons and robustness reasons.)

lucida

@BryceSummers I think the case where six triangles are formed is when you have a triangle at the corner of the cube positioned such that only the tips of the three corners stick out of the cube. This creates a hexagon, which must be represented as 6 triangles.