Trapcode Particular
Layer Maps Group
Color and Alpha group
The Color and Alpha group lets you use a layer to control the particle field with the color and alpha channels. The colors are used for each particle from the RGB channels. The alpha channel defines transparency, making the particles 100% transparent where the alpha channel in the layer is black.
At left, a precomp of a shape layer star with color and alpha information. In the middle is a particle field. At right, the precomp is applied as the Color and Alpha map to the particle field with Functionality at RGBA to RGBA and Map Over set to XY. Notice any color choice you have applied to your particles previously is ignored in favor of the color from the source layer. If you wish to retain your color selection, you will want to select A to A or Lightness to A.
Color and Alpha > Functionality pop-up: Sets how the particles interact with the layer map's color and alpha properties.
- RGB to RGB: Maps the color values to the particle colors.
- RGBA to RGBA: Maps color to the particle color and the alpha channel to the particle opacity across the field.
- A to A: Alpha to Alpha, which maps the alpha channel of the source layer to the opacity of each particle in the field.
- Lightness to A: Lightness to Alpha, which maps the luminosity (the brightness of individual pixels) to the opacity values of the particles. Luminosity is useful for input layers that have transparency information stored as an RGB image.