TexmapColor 

One of the advanced helper nodes is the TexmapColor Helper. This helper works in conjunction with the MatterWaves operator to get the current surface color of a map. TexmapColor uses the UVW or Position input to determine the color value at that coordinate. When used In conjunction with pyrocluster, it allows you to control the volumetrics color based on the surface color of an object.

Another use of this helper could be to "sort" or specify particles based on the texture color they are emitted from.

Operator Inputs 

ON - (Bool) This input data stream determines whether the operator is considered 'on' or 'off.' You can connect other operators to this input channel such as a Bool Helper to activate/deactivate the whole operator.

Time - (Time) This input data stream is used to define the local time for the operator when the user wants to override the default system time.

UVW - (Vector) This input data stream allows any operator condition to be used to input a UVW coordinate that is to be read.

Surface Position - (Vector) This input data stream can be connected to any channel that supplies a Point3 (X,Y,Z) value.

Operator Outputs 

Color - (Color) This output data stream carries the current color based on the UVW or Surface Position input value.

Alpha - (Scalar) This output data stream supplies the current Alpha value of the point based on the UVW or Surface Position input value

Rollout Menu 

Preview On - Activate this checkbox to see the mini-map preview window.

Map Blur - Increase this spinner's value to blur the selected map. This is useful when you want to reduce noise in the map and to even out the results.

Map Slot - Click the button that says "NONE" by default to bring up a standard Material/Map browser. Select any texture map from the available options as the source image.

Example:




In the sample setup shown above, a MatterWaves emitter creates particles and stores them in a group called Particles. All particles created into this group depend on the further processing from the above shown rules.







The group named Particles has an added DataChannel output data stream #0 (called CH:UVW). From this port the TexmapColor helper gets its UVW channel. MatterWaves on the other hand, creates particles stored in the group named Particles along with the extra DataChannel information holding the UVW coordinates. This UVW "value transfer" is done and prepared in two places of thinkingParticles, in the Particle Group rollout menu (assigning a Data Channel) and in the MatterWaves Write to Channel rollout section. From within the MatterWaves Write to Channel rollout, the UVW Channel and the DataChannel number of the Particle group may be chosen. In this example Channel #0 is used for holding UVW data.

What does TexmapColor do? 

Based on the UVW channel coordinates, TexmapColor calculates the relevant shading color based on the selected texture map and UVW coordinate. This color value may then be used as a trigger to do some modifications to particles or other objects in the scene. In the sample setup shown above, a Threshold condition is used to sort particles based on the surface color of a selected object. A white surface color (threshold 1.0) will assign the particles to the White Teapot particle group, a black surface color (threshold 0.0) will assign the particles to the Black Teapot group. The result of the above mentioned DynamicSet looks like the illustration shown below. Note, the "black" teapots are blue in this image (for better visibility). The black checker fields emit black teapots (here they are blue) and the white checker fields create white teapots. This will even work with an animated map.