This page provides information about V-Ray Scatter in V-Ray for SketchUp.
Overview
The V-Ray Scatter tool creates instances of objects using the surface of another object to generate points.
UI Paths
||Asset Editor|| > Geometries (right-click) > Scatter
||Asset Editor|| > Create Asset (left-click) > Geometries > Scatter
||V-Ray Objects Toolbar|| > Scatter over Selection
||V-Ray Objects Toolbar|| > Scatter Viewer
||Extensions|| > V-Ray > V-Ray Objects > Scatter over Selection
||Extensions|| > V-Ray > V-Ray Objects > Scatter Viewer
Creating V-Ray Scatter
V-Ray Scatter consists of two types of objects – Host objects and Guest objects that are scattered over the Host object's surface. There are several ways to create Scatter host and Guest objects.
Creating Scatter Host objects:
Select an object in the viewport. Click the Scatter button from the V-Ray Geometry Toolbar.
Select an object in the viewport. Go to the Extensions menu > V-Ray > V-Ray objects > Scatter over Selection.
Select an object in the viewport. Open the Asset Editor > Geometry > Scatter and use the Apply to Selection option.
The V-Ray Scatter button in the V-Ray Geometry Toolbar is inactive until an object is selected in the viewport window. When you select an object in the scene the V-Ray Scatter button becomes active.
A bounding box with a Scatter icon appears around the Host object upon creation.
Creating Scatter Guest objects:
Select an object in the viewport and use the Add Guests button in the Asset Editor. The object appears under the Add Guests button.
- Quick way to introduce a Guest object is to drag and drop a preselected object from the viewport on to the Host object. In this case the Guest object can be removed by using the drag + shift function. Scatter Viewer must be active in order to add a Guest object by dragging a preselected object from the viewport on to the Host object.
The only special objects that can be used as Scatter Guests are Proxy Mesh objects.
SketchUp component used as Scatter guest needs to have the component instance present in the scene in order to scatter it. Deleting the instance will remove the guest despite the component still being present in the SketchUp project. The extra object can be manually hidden (right-click > hide), placed in a separate hidden layer or moved on the Scatter host surface after scattering.
Example of introducing Guest objects to the Host object by drag and drop.
Parameters
Density – Determines the approximate count of instances in a square meter. When a texture is used, the density value can still be used. Black color in the texture discards all instances in the area. Areas colored with white receive maximum density.
Seed – Controls the random seed of the Scatter. Change this integer value to get a different random distribution.
Axis Filter – Filters the faces that will be used for instance positioning.
All Faces – The points/instances are generated uniformly on all object faces.
Facing Up – The points/instances are only placed on object faces oriented upwards in the scene. Note that host component transformations are ignored.
Orientation – Specifies the initial orientation of the instances.
World Up – All instances are positioned upright independent of the base/host surface face normals.
Along Normals – The instances are oriented based on the base surface face normals.
Collision Detection – When enabled, instances with overlapping bounding boxes will be discarded. Eliminating collisions will reduce the initial density count and may alter the predetermined ratio between multiple guests.
Add Guests – Adds the currently selected scene objects to the Guests list. The objects in this list are scattered on the base geometry.
Probability – Determines the relative probability of the guest to appear. For more information see the Probability Example below.
Scatter Viewer must be activated prior to selecting special objects in the scene viewport in order to add them as Guests.
Guest Origin – Determines how the objects are positioned relative to the random Scatter points.
Bounding box bottom center – The bounding box bottom center of the object is matched to the instance point.
Bounding box volume center – The bounding box volume center snaps to the instance point.
Object origin – The original object origin point snaps to the instance point.
Preview Mode – Changes between a Bounding Box or Point Preview for the instances. Note that the point positions are determined by the origin of the guest.
Preview Percentage – Limits the number of previews displayed in the viewport. Use this to optimize the viewport performance.
Probability Example
This is an example of introducing multiple Guest objects with different probability to one Host object.
Rotation
Rotation Min – Minimum angle for the random instance rotation around its up axis.
Rotation Max – Maximum angle for the random instance rotation around its up axis.
Scale
Random Min – Minimum factor for the random instance scaling.
Random Max – Maximum factor for the random instance scaling.
Scale Multiplier – Uniform scale multiplier for the instances. This value is combined with the random scaling.
Notes
- Special objects can be removed from geometry by double clicking on the group/component, selecting the special object's widget and then selecting the Erase option from the context menu (right-click to open the context menu).