Blender: Pyro Source Spread Node

Inspired by the 'Pyro Source Spread' node from Houdini, this geometry node can be used in exactly the same way to create the same effects seen in many Houdini tutorials.

This node utilizes simulation nodes to diffuse a temperature attribute and ignite the surface of the given geometry.

Update V2.0: Added a 'Temperature Point' node to replace the 'Source Input' so that the user can plug in multiple source points if they want, simply by using a 'math' node to add multiple Temperature Point nodes together.

Update V2.1: Added a Start Frame option and a Continuous option to the Temperature Point node so that the user can continuously apply the temperature point to the simulation, allowing the user to move the source point as it burns the surface.