How to address a color transparency/opacity without touching the color itself? V5

Question

For example I have these color variables:

Color1 = #334455FF
Color2 = #33445588

The only difference is the opacity/transparency component. Can we address this component only, without touching the RGB comps.? For example (improvised obvious syntax concept):

Color1 = #334455FF
Color2 = @Color1, opacity=50

I think there was some similar function in V4 … (I just wasn't here in that era.)

Answer 1

transp = input.int(0, minval=0,maxval=100)
colbase = input.color(color.yellow)

var color _col = na 

_col := color.new(colbase, transp)

plot(close,'close',_col,3)

Answer 2

I believe you are looking for the color.t() function.

Retrieves the color's transparency.

//@version=5
indicator("color.t", overlay=true)
plot(color.t(color.new(color.red, 50)))

Edit:

You can use the color.r(), color.g(), color.b() functions to get the r, g, b components of a color. Then use the color.rgb() function to create a new color.

// This source code is subject to the terms of the Mozilla Public License 2.0 at https://mozilla.org/MPL/2.0/
// © vitruvius

//@version=5
indicator("My script")

color1 = color.new(#c9ff73, 0)

color_r = color.r(color1)
color_g = color.g(color1)
color_b = color.b(color1)

color2 = color.rgb(color_r, color_g, color_b, 25)
color3 = color.rgb(color_r, color_g, color_b, 50)
color4 = color.rgb(color_r, color_g, color_b, 75)

plot(0, "1", color1, linewidth=5)
plot(5, "2", color2, linewidth=5)
plot(10, "3", color3, linewidth=5)
plot(15, "4", color4, linewidth=5)