This blend mode uses the brightness value of the light to limit the brightness of the underlying canvas values.
This is the blend mode used for the SunShade light.
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This chart is useful for understanding how the low pass blend mode works. See how the pixels are clamped on the middle chart, and the lowest values raised to meet the lights value on the right hand chart.
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New in Tungsten
The alpha of the light is now taken into account when using Low Pass blend mode.
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