Google Cardboard

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TkSilver
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Re: Google Cardboard

Post by TkSilver » Fri Oct 23, 2015 12:48 pm

ericbazinga wrote:Does anyone know how PPSSPP's 3D works? I searched the web but couldn't find anything.
Well the google cardbord version takes the immafe that would be placed on the screen and splits it in 2. Each immage is slightly distorted to counter the distortion stereoscopic 3d causes. The new dual immages are then displayed at a custom position on the screen dictated by the focal point of lenses used in making the google cardboard (and set in the settings). The rest is just the funny way the eyes react if seperated from eachother and shown basically the same thing our brain combines the immages creating a 3d effect.

Differences in ppsspp and DraStic that makes this harder.
1. The DS already has 2 distinct physical screens already each controlled by a different renderer (not sure if that means also different physical chips though). The psp only displays one screen (unless you count metal gear acid's Acid eye feature, which is a google cardboard before google. Though they were still not the first to do this.) So instead of having to render 2 screens doing the same thing you have to render 4 screens with 1 pair showing one thing and one showing annother.

2. ppsspp is built using opengl. Google cardboard development tools (both of them) require opengl. DraStic for what ever reason that Exo has uses the cpu to do all the heavy lifting. Somthe code would have to be massively changed to a different rendering engine to even work with cardboard. With no guarenty it would be as fast or as compatible with as many phones as DraStic is today. (Do you realize how amazing it is that DraStic runs as well as it does on so many devices even including dual core phones)
Jay Haru wrote: this has already been discussed and the answer to that is that its not that simple as you think. doing things 3d would double EVERYTHING as it has to emulate the game twice.


At the very least (unless you go with eric's oculus rift level idea) it would not require the game to emulated any more times then it already is. What it woukd require is everything emulated to be fed to the gpu (... lag) then coppied (both screens ..... more lag) then poperly distorted to counter lense distortions and resized (... even more lag) then displayed. Or an entirely new opengl based ds emulator would need to be made.... well at least there are some of those ds4droid .... ect.


One last thing to think about. While some games can be played without the touch screen part of the ds at all. How are you going to touch the screen if it is attached to your face for the games that require it?

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ericbazinga
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Re: Google Cardboard

Post by ericbazinga » Fri Oct 23, 2015 4:38 pm

TkSilver wrote:
ericbazinga wrote:Does anyone know how PPSSPP's 3D works? I searched the web but couldn't find anything.
Well the google cardbord version takes the immafe that would be placed on the screen and splits it in 2. Each immage is slightly distorted to counter the distortion stereoscopic 3d causes. The new dual immages are then displayed at a custom position on the screen dictated by the focal point of lenses used in making the google cardboard (and set in the settings). The rest is just the funny way the eyes react if seperated from eachother and shown basically the same thing our brain combines the immages creating a 3d effect.

Differences in ppsspp and DraStic that makes this harder.
1. The DS already has 2 distinct physical screens already each controlled by a different renderer (not sure if that means also different physical chips though). The psp only displays one screen (unless you count metal gear acid's Acid eye feature, which is a google cardboard before google. Though they were still not the first to do this.) So instead of having to render 2 screens doing the same thing you have to render 4 screens with 1 pair showing one thing and one showing annother.
Maybe a setting where it just renders one screen in 3D and the other 2D (top or bottom screen, depends on which is showing the action).
TkSilver wrote:2. ppsspp is built using opengl. Google cardboard development tools (both of them) require opengl. DraStic for what ever reason that Exo has uses the cpu to do all the heavy lifting. Somthe code would have to be massively changed to a different rendering engine to even work with cardboard. With no guarenty it would be as fast or as compatible with as many phones as DraStic is today. (Do you realize how amazing it is that DraStic runs as well as it does on so many devices even including dual core phones)
Yeah the 3D screen would have to be rendered using OpenGL, but the 2D screen and everything else could be run the conventional way.
TkSilver wrote:
Jay Haru wrote: this has already been discussed and the answer to that is that its not that simple as you think. doing things 3d would double EVERYTHING as it has to emulate the game twice.


At the very least (unless you go with eric's oculus rift level idea) it would not require the game to emulated any more times then it already is. What it woukd require is everything emulated to be fed to the gpu (... lag) then coppied (both screens ..... more lag) then poperly distorted to counter lense distortions and resized (... even more lag) then displayed. Or an entirely new opengl based ds emulator would need to be made.... well at least there are some of those ds4droid .... ect.
Well, it takes a decently-beefed phone to run Google Cardboard in general, so it shouldn't me much of an issue.
TkSilver wrote:One last thing to think about. While some games can be played without the touch screen part of the ds at all. How are you going to touch the screen if it is attached to your face for the games that require it?
Perhaps a touchpad or a PS4 controller? I dunno.
There's a setting that allows you to use the C-Stick on your controller as touchscreen input, so that should somewhat work. Yeah some games that require the touchscreen for control (LEGO Harry Potter comes to mind for some reason) will be incompatible with the feature, but I think it's worth a go. After all, it's the closest thing to a 3DS emulator we'll be getting for a good long while.
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You can also find me on Reddit (u/Ericbazinga) and Discord (in the DraStic Discord server). You'll find me in those places almost daily and here almost never.

TkSilver
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Re: Google Cardboard

Post by TkSilver » Fri Oct 23, 2015 9:31 pm

ericbazinga wrote:Maybe a setting where it just renders one screen in 3D and the other 2D (top or bottom screen, depends on which is showing the action).

Yeah the 3D screen would have to be rendered using OpenGL, but the 2D screen and everything else could be run the conventional way.
If you are wanting to use google cardboard then it is all or nothing as far as stereoscopic 3d or not. You can't render half the screen in stereo and not the other half. It just physically does not work like that. Cardboard and other devices or 3d attempts using the same effect require physical seperation of what each eye views. That means there can not be any area that is shared with eadh eye and therefor only drawn once.

Even if you could do that I will leave exo to explain why trying to use software (ie cpu rendering) for one screen and hardware (ie gpu rendering, opengl) for a different screen would cause issues and would be better to just do the whole thing gpu if it had to be done.
ericbazinga wrote: Well, it takes a decently-beefed phone to run Google Cardboard in general, so it shouldn't me much of an issue.
If your talking about google cardboard's way of creating 3d it actually is fairly efficient since it is not really true 3d. (don't get me started on why VR is not really VR at all and at best finally 3d) Cardboard at it's heart is just an optical illusion and one that makes our brains do all the real heavy graphical lifting, using a software error all humans have. So yes it is not that hard to do and hence why it can run on phone hardware levels.

Now if you are talking about oculus rift/ the trick dolphin was using now you are getting in to a. System that requires a radeon 290x or nvidia gtx780 with a high end core i5 level of processing power (ie estimated system costs or around 1k to be oculus ready). Those are kinda min specs if you want to run emulation on top of that with all the pretty bells (AA and upscaling) and whistles (texture filtering and 60 fps or more stable so you don't get sick) then it takes a beefier system. Something closer to gtx980s in sli and a core i7. But in either case no phone is anywhere close to either type of setup and only a few laptops made this year with desktop class graphics could do it.

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ericbazinga
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Re: Google Cardboard

Post by ericbazinga » Fri Oct 23, 2015 11:06 pm

TkSilver wrote:
ericbazinga wrote: Well, it takes a decently-beefed phone to run Google Cardboard in general, so it shouldn't me much of an issue.
If your talking about google cardboard's way of creating 3d it actually is fairly efficient since it is not really true 3d. (don't get me started on why VR is not really VR at all and at best finally 3d) Cardboard at it's heart is just an optical illusion and one that makes our brains do all the real heavy graphical lifting, using a software error all humans have. So yes it is not that hard to do and hence why it can run on phone hardware levels.

Now if you are talking about oculus rift/ the trick dolphin was using now you are getting in to a. System that requires a radeon 290x or nvidia gtx780 with a high end core i5 level of processing power (ie estimated system costs or around 1k to be oculus ready). Those are kinda min specs if you want to run emulation on top of that with all the pretty bells (AA and upscaling) and whistles (texture filtering and 60 fps or more stable so you don't get sick) then it takes a beefier system. Something closer to gtx980s in sli and a core i7. But in either case no phone is anywhere close to either type of setup and only a few laptops made this year with desktop class graphics could do it.
So if Google Cardboard is somewhat lightweight processing (due to the 3D eye illusion doing most of the work, like you said), then that should leave plenty of power for the emulator (well, it depends on what phone you have, but most are decently powerful). Really, I think the only way to find out if this works is to do a test. I'd love to test for you, but my phone is (unfortunately) too small for Google Cardboard. :-(
One last thought: if we can't get Google Cardboard to work, how about Samsung Gear VR? Samsung phones always pack a good punch, so it sounds promising.
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You can also find me on Reddit (u/Ericbazinga) and Discord (in the DraStic Discord server). You'll find me in those places almost daily and here almost never.

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