This page provides general information about the Smoke Color sub-section of the Rendering rollout of Phoenix FD.

Overview

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This rollout controls the diffuse color of the volumetric shader. The smoke color is affected by lights and shadows, unlike the color and transparency that can be achieved from the Fire rollout. The diffuse color can be a uniform Constant Color, a mixture of RGB colors advected by the simulation, a function of any loaded cache channel, or it can be sampled from a texture.

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Reset to Defaults  – Resets the settings to their default values.

Color gradient – By default, this parameter will be inactive when using the Based on: Constant Color setting for photorealistic smoke. If Based on is set to a Phoenix FD channel such as Smoke, the gradient controls how the smoke color is driven by this channel's value. The selected channel's data range will be highlighted in light blue – When the Based on option is set to a grid channel, this color gradient remaps grid simulation data to render smoke color. The sim data channel is laid out horizontally along the X axis in the color gradient.

This sim data has different ranges, depending on the solver it came from - Phoenix Smoke usually goes from 0-1; Fuel goes from 0-1; Temperature is in Kelvins, so it goes from 300-2000, or a few thousand; Speed is in Voxels/sec, so it depends on the grid size and resolution, but usually goes from 0 to several hundred. Data from other solvers often differs a lot from Phoenix ranges. The channel data range is highlighted in the gradient with a light-blue range which can change as you scroll the timeline as the temperature in a cache file rises, smoke dissipates, speed changes, etc., so keep in mind that the data range for one frame might not be representative for the entire cache sequence. You can also check the data ranges for the currently loaded cache file under the Simulation rollout of Phoenix.

Constant color | difSimpleColor – If Based on is set to Constant Color, this color is used.

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