Point Generator Distribution ShaderShader
Here, points can be distributed based on a a texture’s grayscale values.
A name can be freely defined for the Point Generator. This name will also be displayed in the Sources list.
There are basically 2 ways textures can be assigned to an object to be fractured:
- Using an additional Material tag (with any projection type)
- Easier: using a shader loaded here (with UVW projection)
If the first method is used, the material channel of the Material tag’s material in which the texture lies can be defined.
If Channel is not set to Custom Shader, only the Material tag can be placed here, which will be used to define the material with the corresponding shader.
If Channel is set to Custom Shader, any shader can be loaded here, which will be projected onto the object using UV mapping (Sample Mode set to Surface) and used to distribute a definable number of points across the surface (for 3D shaders across volume as well) based on the shader’s grayscale values. Normally you will use a black bitmap with white regions. The number of points defined in the Point Amount setting will be randomly distributed per UV tile across the white regions. If you use different grayscales, the probability of the point positions to be distributed will be split according to the grayscales.
You can select from the following:
Points will be generated within the object’s bounding box and are designed for use with 3D shaders (if a 2D shader is applied, the texture would move along the Z axis (of the Voronoi Fracture object) within the bounding box; white regions define the volume (similar to an Extrude object)).
Points will initially be generated on the object surface (this can, however, be changed using the Sample Depth setting).
Use this setting to define the number of points that should be distributed in total (Sample Mode = Volume) or per UV tils (Sample Mode = Surface).
When the points are distributed, a grid pattern will be created internally on whose intersecting points the points will be randomly distributed. The Sample Precision value defines the grid’s density. Generally speaking, the larger the Point Amount value, the greater the Sample Precision should be in order to dissolve the grid structure.
Use this setting to modify the random point distribution (see also Seed Values).
When set to the default value of 0, the points will lie on the object surface. Larger values define deeper regions along the surface Normals that lie beneath the object surface in which the points will be randomly distributed. If the value is large enough, the points will exit through the object’s opposite side.
If multiple objects to be broken down lie in the Voronoi Fracture object, this option defines if the vertex dispersion should be calculated with the common bounding box (incl. vertex count) of all respective objects (option disabled) or with a bounding box/vertex count per object (option enabled). For the former, the Voronoi fragmentation will be identical for overlapping objects where they overlap. If this option is enabled, the vertices will be colored red to indicate that the calculation is being made per object.
Mapping
Offset U [-∞..+∞]
Offset V [-∞..+∞]
Length U [-∞..+∞%]
Length V [-∞..+∞%]
If Channel is set to Custom Shader, several settings will be displayed that can be used to move (offset) or scale (length) the texture within the UV coordinates. When working with Noise shaders, Space should be set to UV (2D).
Use this setting to define whether or not the texture should be tiled.
Alpha
Use these settings to define how the Voronoi Fracture shader colors should be processed:
- Alpha: If the shader or texture (e.g., a video) has an alpha channel it will be evaluated; if no alpha channel is present, the texture’s gray value will be used.
- Gray: The gray value will be used.
- Red, Green, Blue: Only the respective color component will be accounted for.
Inverts the alpha channel and its effect.