[SOLVED] Doing intersection test between two Shapes

[ashwin.sudhir]

Is there some way of doing an intersection test between two Shapes?

All the intersection tests that I could find were only for Ray-Shape, AABB-Shape and Regular Frustum-Shape

 

I am looking for something like

bool engine.physics.Intersecting(Shape a, Shape b )

 

Even if that's not possible, is there some way to use a a non-regular frustum (an arbitrary plane bounded volume) for intersection testing?

I cannot see how we can specify a non-regular frustum using the (projection, modelview) format.

 

The goal is to implement drag selection and my understanding is that projecting a rectangle from 2D-projected space onto world-space will (potentially) create a non-regular frustum.

 

Is there another approach to implementing drag selection?

 

Thanks,

Ashwin.

[manguste]

Is there some way of doing an intersection test between two Shapes?

Function to check intersections between shapes is added to the wish list; it will be implemented in the near future.

 

 

Even if that's not possible, is there some way to use a a non-regular frustum (an arbitrary plane bounded volume) for intersection testing? I cannot see how we can specify a non-regular frustum using the (projection, modelview) format.

Why, with projection and modelview matrices you can set whatever non-regular frustum you need; it doesn't have to be symmetrical.

[ashwin.sudhir]

Thanks for the answer, manguste. I have tried to find a reference for a method to convert a set of 6 arbitrary planes to a frustum described using the (projection, transformation) format, but without luck. Can you point me to a book/resource that can help me do this?

The closest I've got to this is to maybe transform a regular frustum using shear transformations, but even that did not give me the control I needed. As far as I can see, the math functions in Unigine (like frustum() )can only construct regular frusta.

 

Thanks in advance,

Ashwin.

[manguste]

What you definitely can do is create a frustum that

* is asymmetrical

* has the upper base nonparallel to the lower one

As for constructing if from 6 arbitrary planes, sorry, it's hard to give a straight answer here, whether it is possible or not. It's not the obvious one.