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[MBS] Gamma fade problems (MBS Xojo Plugin Mailinglist archive)

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Re: [MBS] MIDI Destinations and External Devices   -   Ron Benditt
  [MBS] Gamma fade problems   -   Mike D.
   Re: [MBS] Gamma fade problems   -   Christian Schmitz
   Re: [MBS] Gamma fade problems   -   Mike D.
   Re: [MBS] Gamma fade problems   -   Mike D.
    Re: [MBS] Gamma fade problems   -   Christian Schmitz

[MBS] Gamma fade problems
Date: 15.01.03 09:32 (Wed, 15 Jan 2003 00:32:29 -0800)
From: Mike D.
Using 2.9 release, I'm finding two issues with gamma fades:

(1) (big problem) On some windows machines, a gamma fade to zero
never reaches zero (gets perhaps to 30% brightness).

My code:

myDisplay = GetDisplay(0)
if myDisplay <> nil then
myDisplay.fadeGammaTo(0,RGB(0,0,0),500)
end if

This is on a Dell desktop running Windows XP Home edition with the
monitor set to 1280x1024xmillions on a 16MB ATI Rage 128 Ultra
display.

(2) (minor problem) On some mac systems (older PPC 180s running
System 9.1) the gamma fade is very slow. I can live with this, but
wonder if it's a known issue?

Re: [MBS] Gamma fade problems
Date: 15.01.03 12:14 (Wed, 15 Jan 2003 12:14:01 +0100)
From: Christian Schmitz
> This is on a Dell desktop running Windows XP Home edition with the
> monitor set to 1280x1024xmillions on a 16MB ATI Rage 128 Ultra
> display.

I think I can't do anything because I control directly the Gamma values
and if I set everything to 0 it should be 0!?

> (2) (minor problem) On some mac systems (older PPC 180s running
> System 9.1) the gamma fade is very slow. I can live with this, but
> wonder if it's a known issue?

No. But you can make your own timer and fade with the last parameter set
to 0.

Can you verify this on another Windows machine?

Mfg
Christian

Re: [MBS] Gamma fade problems
Date: 16.01.03 18:49 (Thu, 16 Jan 2003 09:49:59 -0800)
From: Mike D.
> > This is on a Dell desktop running Windows XP Home edition with the
> > monitor set to 1280x1024xmillions on a 16MB ATI Rage 128 Ultra
> > display.
>
>I think I can't do anything because I control directly the Gamma values
>and if I set everything to 0 it should be 0!?
>
>Can you verify this on another Windows machine?
>
>Mfg
>Christian

I have two windows machines: A generic clone running windows 98,
works fine, and the brand new Dell running Win XP which doesn't work.

I'll try some more debugging / testing.

Re: [MBS] Gamma fade problems
Date: 17.01.03 07:31 (Thu, 16 Jan 2003 22:31:35 -0800)
From: Mike D.
>> > This is on a Dell desktop running Windows XP Home edition with the
>> > monitor set to 1280x1024xmillions on a 16MB ATI Rage 128 Ultra
>> > display.
>>
>>I think I can't do anything because I control directly the Gamma values
>>and if I set everything to 0 it should be 0!?
>>
>>Can you verify this on another Windows machine?
>>
>>Mfg
>>Christian
>
>I have two windows machines: A generic clone running windows 98,
>works fine, and the brand new Dell running Win XP which doesn't work.
>
>I'll try some more debugging / testing.

I created a simple test app, and the gamma fade works fine from 1000
to 500, but any numbers below 500 are stuck at a 50% gamma level.

This page : http://rookscape.com/vbgaming/tutT.php points out that
gamma ramps are signed 16 bit integers. Perhaps you are treating the
values as UINT16s?

Re: [MBS] Gamma fade problems
Date: 17.01.03 15:40 (Fri, 17 Jan 2003 15:40:33 +0100)
From: Christian Schmitz
> I created a simple test app, and the gamma fade works fine from 1000
> to 500, but any numbers below 500 are stuck at a 50% gamma level.

Ok. I think I can change something for the next prerelease there.

mfg
Christian