34 lines
1.3 KiB
Markdown
34 lines
1.3 KiB
Markdown
# Blackbody Node
|
|
|
|
## Description
|
|
|
|
Samples a **Gradient** that simulates the effect of black body radiation.
|
|
The calculations in this node are based on data gathered by Mitchell Charity.
|
|
This node outputs color in linear RGB space and preforms the conversion using a D65 whitepoint and a CIE 1964 10 degree color space.
|
|
For more information, see [What color is a blackbody?](http://www.vendian.org/mncharity/dir3/blackbody/)
|
|
|
|
## Ports
|
|
|
|
| Name | Direction | Type | Binding | Description |
|
|
|:------------ |:-------------|:-----|:---|:---|
|
|
| Temperature | Input | Float | None | Temperature or temperature map in Kelvin to sample. |
|
|
| Out | Output | Vector 3 | None | Intensity represented by color in Vector 3. |
|
|
|
|
## Generated Code Example
|
|
|
|
The following example code represents one possible outcome of this node.
|
|
|
|
```
|
|
void Unity_Blackbody_float(float Temperature, out float3 Out)
|
|
{
|
|
float3 color = float3(255.0, 255.0, 255.0);
|
|
color.x = 56100000. * pow(Temperature,(-3.0 / 2.0)) + 148.0;
|
|
color.y = 100.04 * log(Temperature) - 623.6;
|
|
if (Temperature > 6500.0) color.y = 35200000.0 * pow(Temperature,(-3.0 / 2.0)) + 184.0;
|
|
color.z = 194.18 * log(Temperature) - 1448.6;
|
|
color = clamp(color, 0.0, 255.0)/255.0;
|
|
if (Temperature < 1000.0) color *= Temperature/1000.0;
|
|
Out = color;
|
|
}
|
|
```
|