Versions Compared

Old Version 2

changes.mady.by.user Lyubomira Toshkova

Saved on

compared with

New Version 3

changes.mady.by.user Lyubomira Toshkova

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

The Surface Scattering rollout is part of the Chaos Scatter parameters.

...


UI Text Box
typeinfo
This submenu is only available when the scattering mode is set to 2D - On surfaces.

Random Distribution

...

Section
Random distribution
Column
width60%

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

Count UV channel – Determines the exact number of instances to scatter. If the Per square option is enabled, the scattering is defined by the density. See the Countexample below.Per square – When enabled, the Count amount is multiplied by the specified edge length (value next to Per square). See the Per square example belowUV channel to guide the mapping coordinates. When a custom map is used, this option is disabled, and the UV channel in the Bitmap settings is used instead.

Pattern – Selects from predefined distribution maps or chooses a custom map.

Map – Allows a black and white texture map to be assigned. The map determines how the instances are scattered on the surface. See the Map examples below.

Column
width5%
Column
width35%

Image Removed

Count – Determines the exact number of instances to scatter. If the Per square option is enabled, the scattering is defined by the density. See the Countexample below.

Per square – When enabled, the Count amount is multiplied by the specified edge length (value next to Per square). See the Per square example below.

Column
width5%

Column
width35%

Image Added


...

Anchor
RandomDistributionInstancesCount
Anchor
RandomDistributionInstancesCountRandomDistributionInstancesCount
Anchor
PerSquare
PerSquare

Section
Column
width5%


Column
width45%

Example: Count

This example shows the exact instances count on a target object.

Column
width45%

Example: Per square

The number of instances here is determined by the count combined with the target object's surface size. The value specifies the length of the distribution area's side/edge.

Column
width5%


Section
Column
width5%


Column
width45%
Panel
Image slider
startIndex1
Panel
borderStylenone

01_RandomDistribution_InstancesCount_1000

Count = 1000

Panel
borderStylenone

02_RandomDistribution_InstancesCount_2500

Count = 2500

Panel
borderStylenone

04_RandomDistribution_InstancesCount_10000

Count = 10000

Column
width45%
Panel
Image slider
startIndex2
Panel
borderStylenone

01_PerArea_InstansesCount1000_PerAreaOff

Count = 1000; Per Square = Off

Panel
borderStylenone

03_PerArea_InstansesCount1000_PerArea1000

Count = 1000; Per Square = 1000

Panel
borderStylenone

05_PerArea_InstansesCount1000_PerArea4000

Count = 1000; Per Square = 4000

Panel
borderStylenone

07_PerArea_InstansesCount1_PerArea100

Count = 1; Per Square = 100

Panel
borderStylenone

08_PerArea_InstansesCount1_PerArea1000

Count = 1; Per Square = 1000

Column
width5%



...

Anchor
Density
Density

Example: Map

The Map determines the approximate count of instances based on texture input. Black color in the texture discards all instances in the respective area.

Section
Column
width25%


Column
width45%
Panel
Image slider
startIndex1
Panel
borderStylenone

01_Density_IC5000_CheckerMap

Count = 5000; Checker Map

Panel
borderStylenone

Count = 5000; Noise Map

Panel
borderStylenone

03_Density_IC5000_GradientMap

Count = 5000; Gradient Map

Column
width25%




Position Distribution

...

Section
Column
width60%

UV map

This mode uses UVW mapping to scatter instances in regular patternsspecifies the position of the instances based on a pattern. 

UV channel – Determines the UV channel.

Pattern – Determines a pattern to use for scattering. See the Pattern example below.

Grid – Rectangular grid.

Running grid – Rectangular grid with every other row offset by half of the grid spacing.

Hex grid – Arranges instances into hexagons.

UV channel – Determines the UV channel.

Override by planar mapping – When enabled, a simple planar UVW mapping is created and used instead of the pre-existing UVW channels.

Lock V – When enabled the values of the V coordinate for Spacing, Jitter and Offset are locked to the U coordinate's values.

Spacing [%] – Scales the pattern in UV space. When Spacing is set to 100%, the pattern occupies the whole space. When Spacing is set to 50%, the pattern is repeated twice. See the Spacing [%] example below.

Jitter [%] – Determines what percentage of the instances are randomly placed. When Jitter is set to 0, all instances are placed according to the UVW mapping. When Jitter is set to 100, all instances are randomly placed. See the Jitter [%] example below.

Offset [%] – Offsets the pattern by the given value (in percentages). Keep in mind that 0% and 100% Offset gives the same result, as 100% moves the pattern by one whole repetition. See the Offset examples below.

Column
width5%


Column
width35%

Image RemovedImage Added


...

Anchor
Mode
Mode

Example: Mode

This example shows the difference between Random distribution and UV map modes.

...

Section
Column
width5%


Column
width45%

Example: Pattern 

This example shows the different pattern types.

Column
width45%

Example: Spacing [%]

This example shows how the spacing parameter affects the distances between the instanced model objects.

Column
width5%


...

Section
Column
width25%


Column
width50%

Example: Jitter [%]

This is how Jitter affects the random placement of instanced model objects. When set to 0, all instances are placed according to the UVW mapping. When set to 100, all instances are randomly placed.

Panel
Image slider
startIndex1
Panel
borderStylenone

01_UVGrid_PatternGrid_Jitter_0

Pattern = Grid; Jitter [%] = 0

Panel
borderStylenone

04_UVGrid_PatternGrid_Jitter_1

Pattern = Grid; Jitter [%] = 100

Panel
borderStylenone

05_UVGrid_PatternGrid_Jitter_2

Pattern = Grid; Jitter [%] = 200

Column
width25%


...

Section
Column
width5%


Column
width45%

Example: Offset by Single Axis - V

For this example, the Pattern is set to a rectangular Grid. The offset is applied to the U axis only (the Lock V option is disabled).

Column
width45%

Example: Offset Locked UV

For this example, the Pattern is set to a rectangular Grid. The offset is applied to both the U and V axes (the Lock V option is enabled).

Column
width5%


Section
Column
width5%


Column
width45%
Panel
Image slider
startIndex2
Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 0

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 25

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 50

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 75

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 100

Column
width45%
Panel
Image slider
startIndex2
Panel
borderStylenone

Pattern = Grid; Offset [%] = U 0; V 0

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 25; V 25

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 50; V 50

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 75; V 75

Panel
borderStylenone

Pattern = Grid; Offset [%] = U 100; V 100

Column
width5%




Edge trimming

...

Section
Column
width60%

Edge trimming

Trims elements of instances outside of distribute-on objects. It affects both base objects and include/exclude splines. See the Edge trimming example below. 

UI Text Box
typeinfo

Starting with V-Ray 6, update 1.1, the edge trimming feature is available with Chaos Scatter 2.6.0 and later.


Edge trimming is used to trim scattered instances consisting of multiple mesh elements so that they stay within the boundaries of the distribute-on objects or include/exclude splines. If a pivot of any integral part of the instance (any sub-mesh element of the instanced model) falls outside of the area specified by the scatter, such part is not rendered. This is a simplification, but you can imagine the pivot as a point on the distribute-on object from which an element is growing.

The typical use cases of Edge Trimming include:

Fancy Bullets
typecircle
  • Grass lawns - in case of using large grass clumps, no individual grass blades will be growing outside of the defined area.
  • Carpets - in case of using large clumps of strands, no individual strands will be placed outside of the carpet area.
  • Pebbles, rocks, bark chippings, or any other objects which you need to distribute within some specific boundary and make sure no instances stick outside of that boundary (determined based on the mesh element pivot precision).

In addition to making the scattering look more refined and natural, the edge trimming feature boosts performance by removing some of the instances you save from RAM and making parsing time shorter.

UI Text Box
typetip

If Edge trimming doesn't seem to be working correctly (e.g. some elements of the model are expected to be trimmed, but they are still visible), try resetting the model's XForm in 3ds Max by selecting the model and then going to Command Panel > Utilities and click Reset XForm.

Column
width5%


Column
width35%


...

Anchor
EdgeTrimming
EdgeTrimming

Example: Edge trimming

This example shows how some scattered clumps of flowers are trimmed. The clump of flowers is a single mesh consisting of multiple sub-object elements.

...

Align
aligncenter
HTML
<iframe width="700" height="400" src="https://www.youtube.com/embed/IfqkirzEGXs" title="V-Ray for 3ds Max — Get clean grass edges with Chaos Scatter" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" allowfullscreen></iframe>



Slope Limitation

...

Section
Slope Limitation
Column
width60%

Limits scattering only to 'slopes' at certain angles. It can be used to create realistic spread of trees on curved surfaces, for instance. The lower the Angle range is set, the smaller the angle at which scattering stops.

Angle [°]– Defines a range of angles to which the scattering is limited. Instances outside of this range get filtered out. The angles are measured either between the Local up vector and the surface normal or the World up vector and the surface normal. You can select which up normal to use in the option below. See the Slope Limitation Angle [°] Example.

Local – When enabled, the Slope Limitation is measured according to the up vector of each individual Distribute-on target object. See the Slope Limitation orientation Example.

World – When enabled, the Slope Limitation is measured according to the world Z-axis up vector for all Distribute-on target objects in the scene. See the Slope Limitation orientation Example.

Column
width5%


Column
width35%

...

Anchor
slopeLimExample
slopeLimExample

Example: Slope Limitation Angle [°]

The Slope Limitation Angle [°] removes instances based on the angle of the underlying geometry. This option can be used to remove geometry from steep areas as well as shallow areas.

Section
Column
width25%


Column
width50%
Image slider
Panel
borderStylenone

Image Modified

Slope Limitation = disabled

Panel
borderStylenone

Image Modified

Slope Limitation Angle [°]= 0.0 - 45.0

Panel
borderStylenone

Image Modified

Slope Limitation Angle [°]= 0.0 - 20.0

Panel
borderStylenone

Image Modified

Slope Limitation Angle [°]= 5.0 - 20.0

Column
width25%




...

Anchor
LocalWorld
LocalWorld

Example: Slope Limitation orientation

The Local and World Slope Limitations determine the up-vector. The Local option uses the normals of the Distribute-on target object; the World option uses the Z-axis of the scene. In this example, the Slope Limitation Angle [°] is set to 0.0-45.0.

Section
Column
width25%


Column
width50%
Align
aligncenter

Image_comparison_slider
AddButtonsfalse
LabelBeforeLocal
LabelAfterWorld
AttachmentImageBefore02_SlopeLimit_0-45_Rot_Local.jpg
AttachmentImageAfter03_SlopeLimit_0-45_Rot_World.jpg

Column
width25%




Altitude Limitation

...

Section
Altitude Limitation

Image Removed

Image Removed

Column
width60%

Еnables instances limitation in the given altitude range.

Range – Defines the range of altitude units in World or Position Independent mode. See the Altitude Limitation example below.

World – The altitude of the surface points on each individual distribute-on object is evaluated in world space (after all transforms).

Position Independent – 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 the Altitude limitation 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. See the Altitude Limitation example below.

Edit Instances – Switches to 'Instances' sub-object mode. This allows individual instances to be manipulated. Only the instances visible in the viewport can be edited. This option is only useful for small numbers of instances, otherwise it might cause a crash. If you select 100 or more instances, Chaos Scatter displays a warning. To switch out of this option, click Edit Instances one more time. The edited instances are ignored by the Avoid collisions option, the Include/Exclude splines option, Slope limitation and by Camera clipping.

UI Text Box
typeinfo

Keep in mind that if you edit the original model of the scattered instances, after you've edited them, they will be reset back to their original state. To avoid this, edit your instances after finalizing the state of the original model and the Scatter.

Convert to Max geometry – When enabled, converts the Chaos Scatter instances into 3ds Max instances. This option is only useful for small numbers of instances, otherwise it might cause a crash.

Column
width5%
Column
width35%

...

Example: Altitude Limitation

...

Column
width5%


Column
width35%

Max2024_VRay7Beta_Scatter_EdgeTrimming_AltitudeLimitationImage Added


Image Added


Anchor
altitudeExample
altitudeExample

...

Example: Altitude Limitation

In this example, theAltitude Limitation and the Altitude Limitation Falloff parameters are showcased. Setting the Altitude Range max to 500 cuts off the scattered forest at that height. Adding Falloff thins out the forest at the lower point of the curve.

Section
Column
width25%


Column
width50%
Image slider
Panel
borderStylenone

Image Added

Altitude Limitation = Disabled

Panel
borderStylenone

Image Added

Altitude Limitation Range = 0 - 500

Panel
borderStylenone

Image Added

Altitude Limitation Falloff Curve = ascending

Panel
borderStylenone

Image Added

Altitude Limitation Falloff Curve = descending

Column
width25%




Instance Editor

...

Section
Column
width60%

Edit Instances – Switches to 'Instances' sub-object mode. This allows individual instances to be manipulated. Only the instances visible in the viewport can be edited. This option is only useful for small numbers of instances, otherwise it might cause a crash. If you select 100 or more instances, Chaos Scatter displays a warning. To switch out of this option, click Edit Instances one more time. The edited instances are ignored by the Avoid collisions option, the Include/Exclude splines option, Slope limitation and by Camera clipping.

UI Text Box
typeinfo

Keep in mind that if you edit the original model of the scattered instances, after you've edited them, they are reset back to their original state. To avoid this, edit your instances after finalizing the state of the original model and the Scatter.

Brush – Toggles on and off the paint mode. In this mode, instances are painted by the user in the radius of the painted positions. Right-click on the button to reset the changes

UI Text Box
typenote

This tool is meant for small adjustments to scenes. Using it on a large scale may slow down scattering performance.

Erase – Toggles on and off the erase mode. In this mode all the instances in the radius of painted positions are erased (by editing). Right-click on the button to reset the changes

UI Text Box
typenote

This tool is meant for small adjustments to scenes. Using it on a large scale may slow down scattering performance. 

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 from min 1 to max 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 – When enabled, converts the Chaos Scatter instances into 3ds Max instances. This option is only useful for small numbers of instances, otherwise it might cause a crash.

Column
width5%


Column
width35%

Max2024_VRay7Beta_Scatter_EdgeTrimming_InstanceEditorImage Added


...


Section
Column
width5%


Column
width40%

Example: Brush/Erase

This example shows how the Brush and Erase functions work in the 3ds Max viewport.

Image Added

Column
width10


Column
width40%

Example: Brush/Erase

This example shows how increasing the Brush radius and Painting rate affect the scatter instances.

Image Added

Column
width5%

...

Section
Column
width25%
Column
width50%
Image slider
Panel
borderStylenone

Image Removed

Altitude Limitation = Disabled

Panel
borderStylenone

Image Removed

Altitude Limitation Range = 0 - 500

Panel
borderStylenone

Image Removed

Altitude Limitation Falloff Curve = ascending

Panel
borderStylenone

Image Removed

Altitude Limitation Falloff Curve = descending

Column
width25%




Section
Column
width30%
UI Text Box
sizemedium

Previous:

Spline Scattering

Column
width40%


Column
width30%
UI Text Box
sizemedium

Next:

Bounding Box Scattering