GBA Shaders and Resolution

[Nic Lobo]

As it is not possible to run GBA pixel perfect on a 320x240 display, I've tried different settings to get the best possible result.

Original res is 240x160, so I've set:
custom_viewport_height = "800"
custom_viewport_width = "1200"
That is 5x the original resolution

but the Image is not very sharp using the default settings, also the colors are too bright.

Unsing two shaders made it a lot better:
shader0 = "/opt/retropie/configs/all/retroarch/shaders/shaders/sharp-bilinear.glsl"
shader1 = "/home/pi/.config/retroarch/shaders/shaders/gamma2.glsl"


I'm using the mGBA Core.

Is there a better solution?

[Porcinus]

You can try to use "vcgencmd scaling_sharpness" command followed by a value, I use 80.
It does a great job on my side on the TFT but no idea on how it behave on HDMI :S
This is not a permanent solution, if you want to do so, you will need to add it to /etc/local.rc, before the last line followed but "&".
With this solution, you don't need to change the viewport size

For the too bright color, I am not sure of what you mean.
What revison of the motherboard do you have? (last one have ABXY pads on the motherboard itself)
If have not the last one, you need the brightness control ribbon cable to be able to dim the screen backlight. You can try to contact Freeplaytech from there shop website as this product is no more in sell, with some luck, you may be able to get your hands on one
If you have the last revision or the brightness control ribbon cable already install, on EmulationStation, go to Retropie menu >Freeplay Brightness control.

I hope I haven't said too much crap, I am not home and don't have the device on hand right now :S

[Nic Lobo]

thanks @Porcinus for the response.

I'll have a look at "vcgencmd scaling_sharpness"

for the brightness issuse it's only the Gameboy Advance Core that is too bright, so I'm fine with the shade I use now.

Cheers