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atomicjarrod

Convexity

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Hello fellow OFP'ers,

I am just starting to use Oxygen for modelling. I have modelled in other programs for many years but never come across the term Convexity. I first thought it had something to do with non planar but checking faces finds those.

I am now assuming it means how angled the shape is or any angles between planes that are less than 90 degrees because when I Convex Hull it appears as though it tries to smooth out the shape more towards like a sphere? A sphere being completely convex? Is this what it is?

Can someone explain exactly what it means in Oxygen and what the implications are if non convexities exist? All the things I have modelled so far detect non convexities when I check.

Also what is the difference between convex hull and component convex hull?

Thanks,

Atomic Jarrod.

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Yes, someone explain these terms. I wanna know too. Especially what do do with the faces that the function finds.

brsseb

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Hey, found out what the Convex Hull funciton does. Here:

In front view, hit F10 to make a circle with faces. In side view, copy it, paste, lock xaxis and drag the copy backwards. Now select both circles, and choose "Convex Hull" function from list. The result is then a cylinder (so you dont have to manually make all the faces to get one).

This is the only use Ive found of it yet (still dont know what the work convex means anyway, but who cares smile.gif . It basically makes it easier to make 3d objects of 2d objects. Quick way to make a block (without using F7) is to use the function together with two planes.

When people talk about convex in o2 modelling its just saying make sure your structures dont have "leaks" (aka missing faces in structures)) that will look funny ingame and ruin the look of the model.

brsseb

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As far as I know, if a model is "convex" it means that it has no "bumps" or holes in it that would cause a plane between any two vertexes in the model to be cut. So imagine yourself drawing lines from all of the vertexes in the model into all other vertexes. If any of these lines go outside the model's "hull" the model is not convex.

Convex models are needed for proper and fast collision detection.

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