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Author Topic: Bicubic scaling for everything, due to GPU supporting it natively.  (Read 3634 times)

133794m3r (OP)

  • Posts: 72
Bicubic scaling for everything, due to GPU supporting it natively.
« on: September 02, 2013, 10:35:24 pm »
As said above the GPU in this thing apparently has hardware to do bicubic filtering or whatever you wish to officially call it, but since it supports it, you guys should add some sort of wrapper function or something similar to make it easier for emulators to take advantage of it, and also obviously homebrew for tv-out/hdmi output. B/c I see no reason to _not_ use it if you have the ability to use the thing in hardware, I was worried about it due to performance taken away(espcieally for more modern things), but since it's got hardware already there I see no reason to use it.

Btw, i got this information in the datasheet for the jz4770 it's on page 6 of the datasheet. It says it's supported, I hope that means that the secondary procssor has that feature built in, as I know bicubic is very slow to do, but the gcw should be able to handle it just fine. I just thought I'd say there here, b/c it seems like a great thing to use especially for when it's done via hdmi-out.

elwing

  • Posts: 186
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #1 on: September 03, 2013, 07:01:17 am »
while it would be nice to have access to this for the TV-out it would defeat the purpose of the low resolution screen for the rest...

Optimus

  • Posts: 108
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #2 on: September 03, 2013, 09:35:37 am »
It is billinear, even modern gfx card don't support bicubic I think.

But yeah, I am not sure if it's possible yet (they still haven't finished writting the OpenGL ES drivers on the GCW, or?)
Not sure if this scaling would blur the graphics though. I'd prefer 1:1 most of the times. And it's quite fast to scale with software rendering too.

pcercuei

  • Posts: 1708
    • My devblog
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #3 on: September 03, 2013, 03:03:30 pm »
Currently, the video driver (video, not GPU) driver we have makes the LCD appear as a standard 320x240 16/32bpp framebuffer.

The long-term plan is to switch to a DRM driver, like radeon/nouveau drivers, and make the driver accept different resolutions than 320x240, and scale them using the IPU (image processing unit). This has multiple benefits: for instance, a game built for 320x240 could show at 720p via HDMI, and a 640x480 game would be scaled down for the internal LCD screen, with bilinear or bicubic scaling applied (as both are supported by the IPU).

Note that this will be done before analog TV-out, as TV-out requires a 640x480 framebuffer while all of our apps are 320x240.

fosamax

  • Posts: 330
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #4 on: September 03, 2013, 04:29:19 pm »
It's really great to see the software evolve, new capabilities added or enhanced day after day.
I still don't have my zero but it's not that bad since as time passes, as its software is more and more polished.

Thank you all devs !

133794m3r (OP)

  • Posts: 72
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #5 on: September 12, 2013, 12:20:06 pm »
ah ok well that's not surprising really(to me at least) since hdmi-out isn't yet in there, and that's really where such things would be needed.

Atlantis_Risen

  • Posts: 535
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #6 on: September 12, 2013, 01:18:02 pm »
I just want analog tv out for CRT TV's...any retro gamer worth  his salt is playing old school games on a TV they were designed for.

opt2not

  • Posts: 210
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #7 on: September 12, 2013, 07:34:41 pm »
I just want analog tv out for CRT TV's...any retro gamer worth  his salt is playing old school games on a TV they were designed for.
Bless your soul. :)

trisoret

  • Posts: 27
Re: Bicubic scaling for everything, due to GPU supporting it natively.
« Reply #8 on: September 28, 2013, 10:52:24 pm »
I just want analog tv out for CRT TV's...any retro gamer worth  his salt is playing old school games on a TV they were designed for.

I couldn't agree more!