Number of bones supported by PSP hardware

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gr8dane
Posts: 16
Joined: Thu Aug 18, 2005 11:10 am

Number of bones supported by PSP hardware

Post by gr8dane »

It seems the PSP hardware supports 8 weights per vertex, does anyone know the maximum number of bones supported by the hardware?

In other words, what is the maximum index supported by sceGuBoneMatrix(Index, Matrix);

Thanks in advance...
chp
Posts: 313
Joined: Wed Jun 23, 2004 7:16 am

Post by chp »

It only supports 8 weights, so that means only 8 matrices. It's not indexed like on the PC where you can use a matrix palette.

If you need to use more than 8 bones, you'll have to slice the model up based on locality.
GE Dominator
gr8dane
Posts: 16
Joined: Thu Aug 18, 2005 11:10 am

Post by gr8dane »

Thanks, that was exactly the answer I did not want to hear :-)

I'll just start crying now...
ector
Posts: 195
Joined: Thu May 12, 2005 10:22 pm

Post by ector »

blah, it can't take more than an afternoon to do a reasonably decent model slicer..
http://www.dtek.chalmers.se/~tronic/PSPTexTool.zip Free texture converter for PSP with source. More to come.
gr8dane
Posts: 16
Joined: Thu Aug 18, 2005 11:10 am

Post by gr8dane »

You are correct, a resonably decent model slicer would not take that long.

However for my purposes "resonably decent" is just not good enough, making an optimal one is a little more complicated.
ector
Posts: 195
Joined: Thu May 12, 2005 10:22 pm

Post by ector »

Doing a perfectly optimal model slicer sounds suspiciously like an NP-complete problem :)

You're probably better off with a more pragmatic solution...
http://www.dtek.chalmers.se/~tronic/PSPTexTool.zip Free texture converter for PSP with source. More to come.
Produkt
Posts: 12
Joined: Mon Aug 15, 2005 10:17 pm

Post by Produkt »

thats really weird... so the hardware seriously cannot track more than 8 bones?


a typical model without feat, head, and hand bones is 9 bones!
gr8dane
Posts: 16
Joined: Thu Aug 18, 2005 11:10 am

Post by gr8dane »

Most any skinned model will use more than 8 bones. You will have to split up your mesh into several sub-meshes based on what polygons are influenced by which bones and then render them seperately.

You can get around the 8 bone hardware limit this way but it's a bit of a pain the ass.
gr8dane
Posts: 16
Joined: Thu Aug 18, 2005 11:10 am

Post by gr8dane »

Does anybody happen to know the performance impact of feeding the hardware 8 weights versus 2 weights?
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