[BUG?] VGA - color brightness

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TheMechanist
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[BUG?] VGA - color brightness

Post by TheMechanist » Sat 14 Apr, 2018 8:27 am

Hi,

seems, that DOSBox and PCem (linux) render the colors differently .. colors look too bright in PCem for the 18bit RGB values ?! It doesn't matter, if software or openGL rendering ..

Image

Greetz

TheMechanist

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SarahWalker
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Re: [BUG?] VGA - color brightness

Post by SarahWalker » Sun 15 Apr, 2018 9:25 pm

What are you running in these screenshots?

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omarsis81
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Re: [BUG?] VGA - color brightness

Post by omarsis81 » Mon 16 Apr, 2018 1:16 am

PCem looks too bright... does it happen on every game?

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leilei
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Re: [BUG?] VGA - color brightness

Post by leilei » Mon 16 Apr, 2018 1:18 am

Is DOSbox in machine=vgaonly?

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TheMechanist
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Re: [BUG?] VGA - color brightness

Post by TheMechanist » Mon 16 Apr, 2018 4:37 am

SarahWalker wrote:
Sun 15 Apr, 2018 9:25 pm
What are you running in these screenshots?
My own project .. using nothing special, just changing colors in mode 13h the usal way with palette registers .. added the RGB value in the left screen to show the difference, its the color of the field where this color is used.

@leilei: its set to svga_et4000 .. changed it now to vgaonly and - same brightness ! wtf ? are there really differences between the chipsets and card ? (at least in PCem it doesn't matter) ..

A RGB value like 1,6,5 should be really dark .. hm ..

btw. the internal font roms are different - the 8x8 vga font's first line is clear in dosbox (the letters points start the second line), in PCem they start with the first line .. I guess it correct in PCem when using the real vga roms !?

Greetz

TheMechanist

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TheMechanist
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Re: [BUG?] VGA - color brightness

Post by TheMechanist » Mon 16 Apr, 2018 10:16 am

hm .. interesting, seems that the green channel has technically a higher brightness level

http://www.vogons.org/viewtopic.php?p=351518#p351518

obviously with vgaonly dosbox tries to be as compatible as possible, so PCem does it correctly ..

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