Allow setting a line's fill area's alpha channel #34
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mo8it
approved these changes
Jul 31, 2024
bircni
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Aug 5, 2024
michalsustr
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Nov 26, 2025
Hey! I'm trying to achieve stacked plot lines and came across [Line::fill](https://docs.rs/egui_plot/latest/egui_plot/struct.Line.html#method.fill), which does exactly what I want. The only problem with drawing the fill area is that a user doesn't have control over the alpha channel. As a result, having multiple fill areas within a single plot causes the colors to blend, which is undesired in my case. See the images below: Current:  Desired:  This change adds `Line::fill_alpha`, which allows a user to explicitly set the alpha channel used for drawing the fill area. The default value for `fill_alpha` remains the same as before, causing this PR to not be a breaking change.
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Hey! I'm trying to achieve stacked plot lines and came across Line::fill, which does exactly what I want. The only problem with drawing the fill area is that a user doesn't have control over the alpha channel. As a result, having multiple fill areas within a single plot causes the colors to blend, which is undesired in my case. See the images below:
Current:
Desired:
This change adds
Line::fill_alpha, which allows a user to explicitly set the alpha channel used for drawing the fill area. The default value forfill_alpharemains the same as before, causing this PR to not be a breaking change.