Exactly What 2d Acceleration Does The Gp2x Processor Have?

[MWeston]

Hello. The datasheet for the processor seems a bit vague in describing what it can do. I see lots of details on the video hardware accelerator, but I am interested in what the 2D features are. This is what little I have read, but I would love to hear from the experts!

- 2 hardware video overlays (might be useful for sega/nintendo emulators with sprites and background layers?)
- Direct 2D interface (so what sort of goodies does that offer?)


Maybe I just have an old version of the datasheet? It's only 322KB. Is there a more complete datasheet or reference manual available? I did try to do a little searching first in case I was repeating someone else's topic, but I didn't find much so hopefully this is new and interesting. So what features in the 2D core are programs (such as emulators) using?

EDIT - Okay, I found a 3.9MB databook in the GP2X wiki (very useful site!). Still curious as to what people are using in their code...

 

[OMars]

Hello. The datasheet for the processor seems a bit vague in describing what it can do. I see lots of details on the video hardware accelerator, but I am interested in what the 2D features are. This is what little I have read, but I would love to hear from the experts!

- 2 hardware video overlays (might be useful for sega/nintendo emulators with sprites and background layers?)
- Direct 2D interface (so what sort of goodies does that offer?)


Maybe I just have an old version of the datasheet? It's only 322KB. Is there a more complete datasheet or reference manual available? I did try to do a little searching first in case I was repeating someone else's topic, but I didn't find much so hopefully this is new and interesting. So what features in the 2D core are programs (such as emulators) using?

EDIT - Okay, I found a 3.9MB databook in the GP2X wiki (very useful site!). Still curious as to what people are using in their code...

Hey there! So how are things going with your project? I hope you have gotten far!
Didn't mean to hijack your thread or anything...

 

[Squidge]

Not many emulators actually use much in the way of 2d hardware because it works on some systems and not on others.

But those that do normally just use the blitter, which can be thought of as just a fast memory copier. Yes, it has lots of ROPs (Raster Opcodes), but I think most (all?) people just use opcode SRCCOPY which means just copy from source to destination address.

I don't think anyone using the rotation hardware, and the mpeg hardware is still limited to mplayer.

 

[Tobriand]

Well, iirc, it works, but there's some odd initialisation that has to be done on some (mine included) for some programs. Possibly involving sound.

I mean, I can run (without running anything beforehand) anything compiled with the HW accellerated SDL libs... I just couldn't run the versions of Squidgesnes that used the blitter without a bit of jiggery pokery with CloneKeen...

But yes, in any event, listen to Squidge

 

[MWeston]

Still working on it Omar, but it's still a design on paper.

Thanks for that response Squidge. I hear people say how important the 2D hardware is, but I didn't think it was being used much. Maybe the PSX emulator is using that stuff in order to get the frame rate up.