Blending is a function used to combine two pixels together in various ratios. Blending is the basic operation of image compositing and is frequently used to create transparency effects.
In blending functions, one pixel is designated as the source and the other is designated as the destination. Blending uses a source blending factor to determine what proportion of the source pixel's color to draw over the destination pixel. The destination pixel also has a blending factor that determines what percentage of its own color will be contributed to the final blended pixel.
The blending equation is:
- Final Pixel Value = (Source Blend Factor * Source Pixel Color) + (Destination Blend Factor * Destination Pixel Color)
In TouchDesigner, blending is a common parameter for most MATs.