Match Alpha

What It Does

The Match Alpha node calculates the opacity value needed to blend a foreground color with a background color to match a reference color. It reverse-engineers the alpha value that would create the target color.

Inputs

Name	Description	Type	Required
Foreground	The color to apply transparency to	Color	No
Background	The background color for blending	Color	No
Reference	The target color to match	Color	No
Threshold	Maximum allowable color difference (0-1)	Number	No
Precision	Calculation precision for alpha value	Number	No

Outputs

Name	Description	Type
In Range	Whether a valid alpha value was found	Boolean
Color	The foreground color with the calculated alpha	Color
Alpha	The calculated alpha value (0-1)	Number

How to Use It

1. Drag the Match Alpha node into your graph.

2. Connect your foreground color (like #5C5656), background color (like #FFF), and reference color (#CFCDCD).

3. Adjust threshold and precision if needed (defaults are 0.01).

4. The node outputs the calculated alpha value (0.3) and the semi-transparent foreground color (#5C56564D).

5. If "In Range" is false, no suitable alpha value could be found.

Tips

• Lower threshold values require more exact color matching.

• If no suitable alpha is found, try different foreground and background colors.

• This node works best when the reference color is between the foreground and background colors.

See Also

• Flatten Alpha: For the reverse operation - merging a transparent color with a background.
• Contrasting Alpha: For finding alpha values that maintain contrast requirements.

Use Cases

• Color System Analysis: Discover the transparency values used in existing designs.

• Overlay Recreation: Recreate the exact transparency of an existing overlay or glass effect.

• Color Harmonization: Find transparency values that harmonize colors in a composition.