Chaos Scatter

Viewport

Instances

Previz type – Selects how to display scattered instances in the viewport. Affects viewport performance.

None – Instances are not displayed at all.
Dot – Each instance is displayed as a single dot.
Box – Each instance is displayed as a solid box.
Wire box – Each instance is displayed as a wire box.
Full – Each instance is displayed as the full mesh.
Point cloud – Displays each instance as a point cloud.

Adaptive previz – Enables Adaptive Full previz mode, which improves responsiveness in case of frequent viewport redraws and large number of instances. In this mode scatter will draw part of instances as full mesh and the rest as boxes, while the user operates actively the viewport, frame slider or the scatter itself.

Max instances – Maximum number of scattered instances being displayed in the viewport. When this limit gets exceeded, some instances are randomly hidden. If increasing this number would display more instances, the label is colored.

Max polygons – Maximum number of polygons (forming scattered instances) being displayed in the viewport. When this limit is exceeded, the instances preview models will be optimized/simplified. If the polygon limit value is below the total polygon of the fully previewed instances the label is colored in orange. If the polygon limit value is below the lower possible polygon number for the visible instances it is colored in blue.

Points – Percentage of points to display when Point cloud representation is selected in the Previz type selection.

Colors
Original wire colors – Selects whether to use wire colors of original instances objects when displaying their instances as dots, point clouds, or wire boxes in the viewport.

Brush Instances Colors
Following – Selects how to color following painted instances in the viewport: Original, Darker or Custom.
Intensity – Sets the intensity of color darkening for following painted instances in the viewport. The value ranges in [0;1], where 0 means full darkening and 1 means no darkening.
Non-Following – Selects how to color non-following painted instances in the viewport.

Edited Instance Color
User Edited – Selects how to color edited instances in the viewport: Original, Darker or Custom.

Icon size – Sets the display size of the selected Scatter object's gizmo.

Update automatically – When disabled, scattering is not recomputed if any of the distribute-on/instanced objects change. The scattering is always recomputed if any parameters of the Scatter object itself change, regardless of this option. 

Update now – Forces recomputation of the scattering.

Limits

Max instances – Limits the maximum number of scattered instances. Note that there is always another mode-dependent parameter (spacing, density, or count) which determines how many instances to scatter. This parameter is intended as a constant value "safety measure" to prevent crashes/freezes from scattering too many instances, e.g. when setting the density too high.

Random Distribution

This mode scatters instances randomly on all mesh and closed spline distribution objects. It is enabled by default.

Random – Scatters randomly on all mesh and closed spline distribution objects.

UV Channel – Specifies which of the UV channels of the distribution objects to consider. When a Custom map is used, this option is disabled and the UV channel is placed in the Bitmap settings is used instead.

Pattern – Choose from the drop-down list which pattern to use for random scattering:

None – Scatters instances uniformly and randomly only based on density (Per square option)
Custom map – Scatters instances randomly based on a custom texture map placed in the Map slot.
Distorted streaks high – Scatters instances randomly in streaks with high density based on a predefined map.
Distorted streaks low – Scatters instances randomly in streaks with low density based on a predefined map.
Groups high – Scatters instances randomly in groups with high density based on a predefined map.
Groups low – Scatters instances randomly in groups with low density based on a predefined map.
Fractal patches high – Scatters instances randomly with high density based on a predefined fractal map.
Fractal patches low – Scatters instances randomly with low density based on a predefined fractal map.
Straight lines high – Scatters instances randomly in straight lines with high density based on a predefined map.
Straight lines low – Scatters instances randomly in straight lines with low density based on a predefined map.
Stretched patches high – Scatters instances randomly in stretched patches with high density based on a predefined map.
Stretched patches low – Scatters instances randomly in stretched patches with low density based on a predefined map.

Count – Defines an exact number of instances to scatter - either overall, or per area in the case of scattering defined by density (Per square option). The number is always limited by the Max. limit option.

Per square – When enabled, the number of instances to scatter is defined by density (Count per square having the given edge length). The number of instances is always limited by the Max. limit option. The specified value is the edge length of a square defining an area for computing the scatter density. The length is measured in world units.

Position Distribution

This mode specifies the position of the instances based on a pattern.

Position - Use UVW mapping to scatter the instances in regular patterns.

UV Channel – Specifies which of the UV channels of the distribution objects to consider.

Pattern – Choose from the drop-down list which pattern to use for patterned scattering:

Grid – Rectangular grid.
Running grid – Rectangular grid with every other row offset by half of the grid spacing.
Hex grid – Arranges instances into hexagons.

Count – Defines an exact number of instances to scatter - either overall, or per area in the case of scattering defined by density (Per square option). The number is always limited by the Max. limit option.

Per square – When enabled, the number of instances to scatter is defined by density (Count per square having the given edge length). The number of instances is always limited by the Max. limit option. The specified value is the edge length of a square defining an area for computing the scatter density. The length is measured in world units.

Override by planar mapping – When enabled, simple planar UVW mapping is applied to the distribution object and used instead of its existing UVW channel.

Lock V – Locks the V coordinate for Spacing, Jitter, and Offset to the same value as the U coordinate.

Spacing [%] – Scales the pattern in UV space - 100% spacing makes the pattern occupy the whole 0-1 UV space; with 50% spacing the pattern gets repeated 2 times in both U and V, etc.
Jitter [%] – Randomly jitters each instance in the the U or V axis, with 0% being entirely deterministic placement (no jitter) and 100% being entirely random placement.
Offset [%] – Offsets the pattern in the UV space. Each 100% added or subtracted moves the pattern by one entire repetition - which means that e.g. 0% and 100% offsets yield the same result.

Clusters

Clusters – Allows the combination of patches of the same instance, thus achieving a more natural look.

Generate – Activates the Generate clustering mode. In this mode, Clusters are created out of the list of objects. The distribution of the clusters is guided by a procedural noise map. The Frequency set for a particular object in the Objects tab determines the size of its Clusters - smaller Frequency results in smaller sized Clusters.

XY / UV – Chooses between system unit distribution or UV mapping coordinates.

UV channel – Specifies the source UV channel for the mapping coordinates. Available when UV is selected.

Seed – Applies different variations of the pattern based on the Seed number. 

Size – Specifies the average size of the clusters on the X and Y axes. The larger the Size value, the larger the Clusters will be. Available when XY is selected.

Scale [%] – Scales the clustering pattern along the UV coordinates. Available when UV is selected.

Rotation – Rotates the clusters around a center. For the UV mapping, it is 0,0 and for XY mapping it is the geometry center of a target object or the common center for all the target objects in the list.

Offset X / Y – Offset along X axis or Y axis. The offset direction depends on the rotation of the clusters. Available when XY is selected.

Offset U / V – Offset along U axis or V axis. The offset direction depends on the rotation of the clusters. Available when UV is selected.

Roughness [%] – Lower values produce rounded clusters, while higher values produce more jagged edges.

Edge blend [%] – Blurs the edges between different clusters. 

Diversity [%] – Allows a small number of objects from the Clusters to appear inside a given Cluster. Smaller values mean that fewer instances are taken from the other clusters. Bigger values mix instances from other clusters.

Paint with instances – Activates the Paint with instances clustering mode. This mode uses layers. The order of the layers defines which of the objects are going to be visible.

New – Creates a new layer. The first layer (the layer with the lowest number) is a base layer, and is always fully populated across the surface. Then, layers placed on top hide the layers underneath. Each layer has a list of objects that are included in it, they will be scattered in the painted areas of that layer.

Remove – Deletes a layer. Note that deleting the base layer will cause the next remaining layer to become a new base layer, and all painting done in that new base layer will be discarded.

Radius – Defines the size of the brush.

Paint – Allows you to paint the actual place where each layer has an effect. The instances are applied over the chosen area where you paint, and the layers beneath the selected layer are covered.

Erase – Removes the instances over the chosen area and reveals the layers beneath the selected layer.

Edge Trimming – In render, trims elements of instances outside of distribute-on objects boundaries. This affects both base objects and include/exclude splines.

Slope Limitation – Enables instances limitation in the given slope range.

Angle – Defines the range of angles, measured in degrees, between either the "Local" or the "World" up vector and the surface normal, to which scattering is limited. Instances scattered outside of this range get filtered out.

Local / World – Specifies which coordinate space to use when computing the slope limitation. Coordinate space of each individual distribute-on object is used when "Local" is selected, and world coordinate space is used for all distribute-on objects when "World" is selected.

Altitude Limitation – Enables instances limitation in the given altitude range.

Range – Defines the range of altitude units either in the "World" or "Position Independent" mode.

World / Position Independent – Specifies which mode to use when computing the altitude limitation. In "World" mode the altitude of the surface points on each individual distribute-on object is evaluated in world space (after all transforms). In "Position independent" mode the altitude of the surface points on each individual distribute-on object is evaluated relative to the object center, while the object rotation and scale still affect the altitude.

Falloff Curve – Opens a falloff curve editor. This allows specifying the density of the scattered objects depending on their altitude. Lowering the point on the left side of the curve results in lowering the density of the objects closer to the minimum altitude range. Lowering the point on the right side of the curve results in lowering the density of the objects close to the maximum altitude range.

Edit Instances – Switches to Instances sub-object mode, allowing you to override individual instances in the viewport. You can move, rotate, scale, or delete them. It is not effective in a greater scale, but may serve well for final touches in small amounts of instances.

Brush – Toggles on and off the paint mode. In this mode, instances are painted by the user in the radius of the painted positions. 

Erase – Toggles on and off the erase mode. In this mode all the instances in the radius of painted positions are erased (by editing).

Brush Radius – Defines the radius of painted brush.
Painting Rate – A number of instances that should be tried to paint upon a brush actions in the brush area. The value ranges in [1,200].
Follow Scatter Rules – When this option is not checked, you can brush outside of specified areas or ignore rules like Avoid Collision, Slope Limitation, Altitude Limitation, Edge Trimming, or Camera Clipping.
Erased Only Placed Instances – When enabled, erase the instances that were painted with the brush.

Convert to Max geometry – Replicates this scatter using 3ds Max instances. This is usable only for a small number of objects.

Translation

From - To – Specifies the translation range for X, Y, and Z axes, in world units.
Map – Specifies the texture map to use for translation.
Mode – Decides how the Map is interpreted to control the translation. RGB maps can be used to control translation in specific axes. Grayscale maps control translation proportionally in all axes.

Map fixed – Black areas of the map represent the From values. White areas represent the To values. Map areas with shades between black and white represent the values between From and To. No randomization occurs.
Random amount – No randomization occurs in black areas of the map. Full randomization occurs in white areas of the map. From and To values specify the lowest and highest translation allowed for the randomization.

Stepping distance – When nonzero, switches the random translation from a continuous to a discrete one, with steps specified by this parameter value. The From and To are still used as bounds. This effect is used only for the selected axes.

Rotation

From - To – Specifies the rotation range for X, Y, and Z axes, in degrees.
Map – Specifies the texture map to use for rotation.
Mode – Decides how the Map is interpreted to control the rotation. RGB maps can be used to control rotation in specific axes. Grayscale maps control rotation proportionally in all axes.

Map fixed – Black areas of the map represent the From values. White areas represent the To values. Map areas with shades between black and white represent the values between From and To. No randomization occurs.
Random amount – No randomization occurs in black areas of the map. Full randomization occurs in white areas of the map. From and To values specify the lowest and highest translation allowed for the randomization.

Stepping angle – When non-zero, switches the random rotation from a continuous to a discrete one, with steps specified by this parameter value. The From and To are still used as bounds. This effect is used only for the selected axes.
Normal vs. Z – Controls the alignment of instances to the surface normals. It blends the surface normal (value of 0) with +Z when the value is above 0, or with -Z when the value is below 0.
Preserve model rotation – When enabled, instances preserve the original rotation of their models (instanced objects). Otherwise, the original rotation is ignored.

Look At – When enabled, instances in a range get turned towards a specified direction.

Target object – Pick an object according to which the direction is calculated. When a geometry object is picked, each instance gets oriented towards the center of the object's bounding box. When a camera object is picked, each instance gets oriented towards the camera. 
Look axis – Selects which of the object's axes gets turned towards the direction.
Reverse – When enabled, the reverse of the selected axis gets turned towards the direction.
Horizontal – When enabled, the selected look-at axis gets turned only within the plane which is perpendicular to the normal.
Falloff distance – Specified the range in which instances get affected by the look-at specifications. When non-zero, only the in-range instances get affected; otherwise, all the instances get affected. There is no effect when a sun object is picked. The way how the instances get affected is determined by the falloff curve. 
Falloff Curve – Opens a falloff curve editor. The curve specifies how the strength of the look-at effect varies across the falloff distance. Lowering the point on the left side of the curve results in lowering the strength closer to the target. Lowering the point on the right side of the curve results in lowering the strength close to the falloff distance. 

Scale

From - To – Specifies the scale range for X, Y, and Z axes, in percent.
Map – Specifies the texture map to use for scaling.
Mode – Decides how the Map is interpreted to control the scale. RGB maps can be used to control scale in specific axes. Grayscale maps control scale proportionally in all axes.

Map fixed – Black areas of the map represent the From values. White areas represent the To values. Map areas with shades between black and white represent the values between From and To. No randomization occurs.
Random amount – No randomization occurs in black areas of the map. Full randomization occurs in white areas of the map. From and To values specify the lowest and highest translation allowed for the randomization.
Legacy – From and To values decide about the overall randomization and are then multiplied by the values of the Map. This means that black areas of the map are always interpreted as zero scale.

Stepping percentage – When non-zero, switches the random scaling from a continuous to a discrete one, with steps specified by this parameter value. The From and To are still used as bounds. This effect is used only for the selected axes.
Uniform scale – When enabled, instances get scaled in all axes using the values for the X axis. When disabled, each axis uses independent values.
Preserve model scale – When enabled, instances preserve the original scale of their models (instanced objects). Otherwise, the original scale is ignored.

Default map – If a material is using some opacity texture in addition to the Edge Trimming map, this texture can be defined here.

Source

Custom map – Uses a custom map as the surface color. You can then randomize this map's hue and gamma using the built-in controls.
Surface diffuse/base map – Automatically uses the distribute-on object's diffuse/base map.

Hue random – Controls randomization of the resulting color hue. The value specifies maximal distance from the original hue (in range of 0-100%) where 0% disables hue randomization and 100% applies maximal hue randomization.

Gamma random – Adds additional randomization of mid-tones (gamma) to the result (in a range of 0-100%), where 0% disables randomization and 100% applies maximal reasonable gamma randomization.