Procedural animated texture generation/Water

Still water

Adapted from https://github.com/UnknownShadow200/ClassiCube/wiki/MInecraft-Classic-lava-animation-algorithm#water

Every frame, for each position in the still water texture array, the respective values for soup_heat, pot_heat and flame_heat are calculated as detailed below:

• Calculates a local_soup_heat equal to the sum of the 3x1 soup_heat neighborhood around the current element.
• Calculates the new soup_heat as the sum of the local_soup_heat divided by 3.3F plus the pot_heat times 0.8F
• Calculates the new pot_heat as the current pot_heat plus the flame_heat times 0.05. pot_heat is clamped to a minimum of 0.
• Calculates the new flame_heat as the current flame_heat minus 0.1F.
  • However, there is a 0.05 in 1 random chance that flame_heat is set to 0.5.

Once the above arrays have been updated, for each pixel in the water texture, the color and alpha values are calculated based on soup_heat:

• Calculates a color_heat as the soup_heat clamped between 0 and 1 inclusive.
• Then it calculates the color components of the pixel as follows:
  • float red = 32 + color_heat^2 * 32
  • float green = 50 + color_heat^2 * 64
  • float blue = 255
  • float alpha = 146 + color_heat^2 * 50

The red, green and blue values are then converted to bytes and assigned to the texture accordingly.

Flowing water

In addition, the flowing water texture also uses a spatial translation to give the appearance of movement. This transformation moves the flowing water texture downwards by one pixel after a fixed amount of time,​ wrapping the bottom layer of the texture back to the top.