On Mon, Jul 4, 2016 at 2:50 PM, simran <simrangamb...@gmail.com> wrote:
> Interestingly though, when i do a colour swap (without any type casting 
> happening now) - the colour problem is still there.

https://github.com/simran91/monkeysee/blob/master/mimage/mimage.go says:

r, g, b, a := colour.RGBA()
column[y] = color.RGBA{uint8(r), uint8(g), uint8(b), uint8(a)}

Don't do that. As https://blog.golang.org/go-image-package says,
"There are three important subtleties about the return values...
Second, the channels have a 16-bit effective range: 100% red is
represented by RGBA returning an r of 65535, not 255."

Thus, when creating an color.RGBA value, you want the high 8 bits, not
the low 8 bits. That second line should be:

column[y] = color.RGBA{uint8(r>>8), uint8(g>>8), uint8(b>>8), uint8(a>>8)}

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