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Related nodes. Attributes.
Luminance is a utility node that takes in a color,
and outputs a luminance value.
Luminance simply means the apparent brightness of a color,
as seen by the human eye. The human eye is not equally sensitive
across the whole spectrum; greens appear brighter than reds, and
reds brighter than blue. For this reason, luminance is calculated
by this equation:
Luminance = 0.3 * red + 0.59 * green + 0.11 * blue
You can use the Luminance node to convert a color image or texture
into a monochrome (black-and-white) image. To do this, connect
the texture's Out Color into the Luminance node's Value attribute,
then connect the Luminance node's Out Value attribute to
all three color channels (R, G, and B) of a shader.
In the table below, imporant attributes have their names
listed in bold in the description column.
| Node name | Parents | Classification | MFn type | Compatible function sets |
|---|
| luminance | node | utility/color:drawdb/shader/operation/luminance | kLuminance | kBase
kNamedObject
kDependencyNode
kLuminance |
Related nodes
blendColors, clamp, lightInfo, gammaCorrect, surfaceLuminance, contrast, rgbToHsv, hsvToRgb, samplerInfo, setRange, resolution, renderQuality, renderGlobals, renderGlobalsList, baseShadingSwitch, singleShadingSwitch, doubleShadingSwitch, tripleShadingSwitch
Attributes (6)
outValue, renderPassMode, value, valueB, valueG, valueR
| Long name (short name) | Type | Default | Flags |
|---|
|
outValue
(o)
| float | 0.0 |   |
|
|
renderPassMode
(arp)
| enum | 1 |    |
|
|
value
(v)
| float3 | 0.0, 0.0, 0.0 | |
|
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