Custom Particle Colors
This is a bitmap used for the lava drop particle effect as it cools during its fall. The height should be 1 pixel but the width can be anything. The x-axis represents the particle's age in game ticks (1/20th of a second). Lava drop particles are generally not visible for the first 40 ticks or so because they start out embedded in the block above, so 90 pixels is a good width. If the particle lives longer than the width of the image, the last pixel is used for the remaining time.
Used for the experience orbs. This image can be any size. The color chosen will move in a sinusoidal pattern from (0,0) to the end of the image. The speed of the sine wave is slowed down by a factor of 4 from vanilla to allow texture packs to have slower pulsing xp orbs than the default. If you want to keep the default speed, simply tile your image 4 times vertically.
Used for the particles given off by mycelium blocks. The image can be any size. A random color is chosen from the bitmap for each new particle.
These particles are fixed colors specified in
Base water particle (splashes, bubbles, drops) color. Biome water color multiplier is applied on top of this value. The value should match the color of your base water texture. If your base water texture is grey (so that you do coloring via a biome palette), you should set this to ffffff.
Base portal particle color. A random multiplier between 0.4 and 1.0 is applied to all three RGB values.