Scratch
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#1 2010-08-25 22:56:45
Why does the "Brightness Effect" go wrong
When I want a black screen (like a black background) to go white, I use a repeat block w/ [change brightness effect by [-1] ], but instead of white, the screen turns blue!!! How do I fix this? I'm using Scratch 2.0 with a Mac and this is sort of important. 
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#2 2010-08-25 22:58:52
Re: Why does the "Brightness Effect" go wrong
The problem is that it doesn't ever make it go white - the brightness effect can only make black turn blue (just as it makes red turn pink-ish). The reason is that black is really just (on computer monitors) a very dark shade of blue.
As an alternative, try making a sprite that's black and put it over a white background, and change the ghost effect
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#3 2010-08-27 01:16:30
Re: Why does the "Brightness Effect" go wrong
skyfish5 wrote:
When I want a black screen (like a black background) to go white, I use a repeat block w/ [change brightness effect by [-1] ], but instead of white, the screen turns blue!!! How do I fix this? I'm using Scratch 2.0 with a Mac and this is sort of important.
I don't think it does that online - one of the few instances where a project will work better online than off.
Scratch doesn't have support for an alpha channel, so it uses pure black as code for transparent. The best black you can make in Scratch is a very deep blue.
[offtopic]You have Scratch 2.0!? 
[/offtopic]
Last edited by bigreader (2010-08-27 01:19:00)
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#4 2010-08-27 01:45:31
Re: Why does the "Brightness Effect" go wrong
skyfish5 wrote:
When I want a black screen (like a black background) to go white, I use a repeat block w/ [change brightness effect by [-1] ], but instead of white, the screen turns blue!!! How do I fix this? I'm using Scratch 2.0 with a Mac and this is sort of important.
Scratch 2.0?
Are you sure you're not using the Experimental Viewer?
If not... is it a fake? 
I fall: It's a tragedy. You fall: It's comedy.
Hmph enjoy your fall - I get a lovely spring... without pans of new leaves.
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#5 2010-08-27 03:45:29
- mathematics
- Scratcher
- Registered: 2009-03-01
- Posts: 1000+
Re: Why does the "Brightness Effect" go wrong
skyfish5 wrote:
I'm using Scratch 2.0 with a Mac and this is sort of important.
I didn't see this sentence at first and now I see it...
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#6 2010-08-27 10:05:29
Re: Why does the "Brightness Effect" go wrong
mathematics wrote:
skyfish5 wrote:
I'm using Scratch 2.0 with a Mac and this is sort of important.
I didn't see this sentence at first and now I see it...
I'm sure he just made a simple mistake.
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#7 2010-08-27 16:42:11
- colorfusion
- Scratcher
- Registered: 2009-10-03
- Posts: 500+
Re: Why does the "Brightness Effect" go wrong
coolstuff wrote:
mathematics wrote:
skyfish5 wrote:
I'm using Scratch 2.0 with a Mac and this is sort of important.
I didn't see this sentence at first and now I see it...
I'm sure he just made a simple mistake.
Either that or he is using experimental viewer.
Or is a top secret beta tester.
Anyway, All the others are correct I thinks.
Scratch uses blacks code as transparent, and the black is just a really dark blue.
Last edited by colorfusion (2010-08-27 16:43:29)
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#8 2010-08-27 17:07:02
Re: Why does the "Brightness Effect" go wrong
coolstuff wrote:
The problem is that it doesn't ever make it go white - the brightness effect can only make black turn blue.
...which is actually convenient. If you have a black button, for example, you can create a really nice blue effect.
But anyway, I'd recommend making a black sprite and increasing the ghost effect to make it fade like coolstuff said.
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