[cairo] alpha blending

[Bill Spitzak]

On 03/25/2015 12:34 PM, Lawrence D'Oliveiro wrote:
> On Wed, 25 Mar 2015 12:18:47 -0700, Bill Spitzak wrote:
>
>> That simulate gamma-corrected compositing (in this case a 50% blend).
>
> Isn’t colour management supposed to solve all that? So that we can do
> all our image processing in a linear colour space.

There could be a switch that says "composite in linear space" and uses 
colour management to convert between the images and linear.

However that is going to be vastly slow and complex, and annoying to 
programs that want to replicate results locally. And the only 
interesting color space is gamma 2.2, so a much faster and simpler 
version of turning only the simulation of this space on/off would be 
much easier, and probably more friendly to software that wants to 
predict the results.