Destruction question about piece generation

[JoeJ]

I'll not implement it so soon, but i need to think about the generated pieces now when i make a preprocessing tool to create the data structure for GI lighting.
Basically i have a huge lightmap, and every face in the world needs its uv space with no overlaps. So nothing special, just a single texture atlas and a single lightmap.

The question is, either precalculate all pieces and their uv's at level loading (you seem to do so in structured fracture demo),
Or generate (and optionally delete) all geometry during runtime (you seem to do so in simple fracture demo), requiring complex uv mangement.

Julio, do you think runtime generation is fast enough to be practical at all?
If you have dynamic generation in mind, can you give some approx number of how much pieces can be generated per step without a noticable slowdown?

The other minor question is how do you create your uv's?
Do you take the scale from the original object? Or is it some fixed relation to world size?
It seems all texels have the same size which is nice and saves me some work.

[Julio Jerez]

Julio, do you think runtime generation is fast enough to be practical at all?
If you have dynamic generation in mind, can you give some approx number of how much pieces can be generated per step without a noticable slowdown?

The tool that build the fracture is fairly fast, but that Fat for tool usage not for realtime generation. Bascially the tool has to build and voronoid map in three D, and it is dealing with lots of data, memory allocation, and heavy extended precision arithmetic.
The algorithm is lean time\, but I will no count on using in real time. I will using by making prefabricated objects.

The other minor question is how do you create your uv's?
Do you take the scale from the original object? Or is it some fixed relation to world size?

The UV is simple, you pass an texture projection matrix and the UV are planar projection on an infinity plane, you can set the scale, in the texture matrix and that seem to do a relatively good job.

BTW I fixed the crash bug in the structured destruction demo, you can try it now.

[JoeJ]

That's good news, makes life easier for me