[GEM-dev] [part_color] and alpha

[IOhannes m zmoelnig]

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On 2014-08-19 18:24, Ticket 228 wrote:
> Using Gem 0.93.3 on Windows 7 32bit.
> 
> I noticed that when using a part_color, the 4th value (alpha
> component) is ignored. I looked at the code, and I think it is line
> 56 of part_color.cpp. When rendering, the color is not passed into
> the function.


i was wondering whether you think that making [part_color] respect the
alpha-value (of the 1st color) is a useful feature for Gem (or whether
it might break your patches).

for a short discussion see [228].

to tear it down: [part_color] allows to specify a domain to "blend"
between two colors. unfortunately only RGB values are taken into
account (Alpha is ignored).
more unfortunate, the current API (as used internally) would only
allow to pass a single alpha-value, so the "blending" would not extend
to opacity. instead we could use the alpha-value of the first color
(instead of the currently fixed value of "1")

what do you think?

fgmasdr
IOhannes




[228] https://sourceforge.net/p/pd-gem/bugs/228/
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