NEW IN R21
Here you can input the color structure to be modified into the node. This will be cached in a freely definable resolution for quicker editing.
A larger resolution requires correspondingly longer render times but also contains more details. If you prefer blurred colors then a lower resolution will help because details will automatically be reduced when the colors are saved. However, a pre-calculation and the caching of the color structure excludes combining color structures that are calculated using 3D samplling such as the Fresnel effect or Ambien Occlusion. Only 2D structures can be used.
This setting offers common methods for calculating textures. The selection of one of these options automatically defines the underlying matrix parameters 1-9 accordingly. These values can be modified manually for custom settings. The following Preset options are available:
This matrix controls the intensity with which the colors of the surrounding texels will be included in the current sample color. The values are feely definable - large or small - and can, for example, be used to create a much more pronounced Box Blur or Edge Detection effect. If you want the original color and brightness values to be included, the matrix can be normalized (enable Normalize Kernal). This will adjust the values of the matrix so they again equal 1 as a whole.
The matrix consists of 9 numeric values that define the degree to which the neighboring texel affects the current sample color. The current sample is always located at the center, at position 5 in the matrix. If all values are set to 1, all neighboring texels will be included equally when a sample is calculated. The result is a slight blur of the input color structure (see Box Blur above). Negative values in the matrix will reduce the degree to which the respective texel will affect the resulting sample color. This can, for example, be seen when using the Emboss option in which the texels at the top left have a greater effect and those at the bottom right of the sample have a correspondingly reduced effect. The values of the matrix should be balanced in order to maintain the overall brightness of the sample. Large positive values should be balanced with equally negative values elsewhere in the matrix. Enabling the Normalize Kernel option will do this automatically.