Color Transform Problem

moopf

OK, I'm having real issues getting setColorTransform to actually transform a colour accurately. I have an image that, if I show in the app displays a particular blue correctly. Thing is, it's a big block of blue and I have a little fill.png that I stretch and colour for things like this to limit the images used.

If I use the image itself I get the nice bright blue, if I use setColorTransform on the white fill png then I don't, I get an insipid blue. The blue in question is: #69b9ec (R: 105 G: 185 B:236). It's not the only colour I'm having problems with in this way though, but it is really obvious. This is testing in the Gideros player on a mac, although the same issues happen on a device as well.

So, is there something strange about the way setColorTransform works that causes these issues? I can't quite understand why I can't setColorTransform to get exactly the same colour as I would if I embedded the full png. Any suggestions?

ar2rsawseen

theoretically, if the image is white (255, 255, 255), then to set RGB values as 105, 185, 236 you would have to set

setColorTransform(105/255, 185/255, 236/255)

or values: (0.41, 0.725, 0.925)

Doesn't it work as expected?

moopf

No it doesn't. I've tried it down to lots of decimal places as well:

setColorTransform(0.411764703,0.725490191,0.92549019,1)

It's not working as I'd expect at all.

atilim

On windows, it has worked exactly I've expected:

local bitmap = Bitmap.new(Texture.new("white.png")) bitmap:setColorTransform(0x69/255, 0xb9/255, 0xec/255) stage:addChild(bitmap)

I'm attaching my white.png.

@moopf can you attach your image while I'm testing on Mac?

edit: also is there a good color picker for Mac?

petec

When I put your #69b9ec setting into my graphics program it gave a failrly light blue like the one attached. Is that what you are seeing?

atilim

I've used DigitalColor Meter.app on Mac and I'm getting #69b9ec on both Gideros Player and @petec's image.

moopf

OK, I've been checking some more. This is a limitation of RGB colourspaces I think now I look at it again. What's happening is that the RGBs are identical but, actually, the colours are slightly different when you look at them in CMYK. I've found a way around it which ends up as the RGB I need to use being #00bcea (0,188,234) to get the blue I actually want. Now to convert the other ones.

atilim

Makes sense. Gideros ignores the PNG's attached color profile. If you have ImageMagick installed, you can strip the color profile by using:

mogrify -strip image.png

http://www.imagemagick.org/script/command-line-options.php#strip

MauMau

So Bitmap also supports :setColorTransform()? According to the docs, it doesn't :-O

ar2rsawseen

@MauMau Sprite supports setColorTransform()
Bitmap inherits from Sprite, so everything Sprite supports, Bitmap also supports

And if you look here, you can also see all inherited methods:
http://docs.giderosmobile.com/reference/gideros/Bitmap#Bitmap