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Shell generator

The Shell generator is a special case version of the Branch generator. It exists only to duplicate a portion of its parent branch at a slightly wider radius. This extra geometry can cover all the parent or only part of it. Use this generator to provide a thin layer of a different bark material around a branch.

Only the properties presented below are editable on shells. The rest of the shell's features are copied from the parent branch.

Generation

Random Seeds

UV Mapping

The properties in this group control the UV coordinate generation.

Style

Set the method by which UVs are computed:

PropertyDescription
Unrestricted No locks. Unlimited tiling for both U and V.
U locked [0,1], V unrestricted Force all U coordinates to be in the range [0.0, 1.0], but allow unlimited V tiling.
U and V locked [0,1] Lock both U and V texture maps to the range [0.0, 1.0].

Extension style

Set the style by which UV coordinates are generated for any nodes that are extensions in this generator.

Property Description
Automatic All extensions will continue the UV mapping from their parent.
Manual (match) UV offsets will be relative to those that would match their parent.
Manual (match u only) U will match exactly, V is free to edit.
Manual (full control) Full control of UV coordinates will be allowed.

U

U coordinates circle the branch.

Absolute

Set the minimum number of times the material tiles around the branch.

+ Relative

The number of additional tiles based on the branch radius and this number are added to the Absolute value above to set the final number of times the material wraps in U. This value is always at least one and is always an integer.

Offset

Shift U values by this amount.

Note: Use variance on this property to make branches each have a random orientation to the U wrapping.

Fractional

U tiling values are forced to the nearest integer value during normal texture coordinate computation to facilitate seamless tiling; however, this is not always desirable. For instance, if you need to target a branch component in a custom atlas you'll need to use fractional values in combination with U offset to focus on a section of the atlas.

Enable

Toggle whether or not fractional U values are allowed. If they are, only the Value property in this group affects the U coordinate.

Auto

Set the value to a number that will result in the closest possible match to the texel density of the parent. There will be a seam in the texture, but it may not be noticeable from the viewpoint of the intended scene.

Value

This property directly sets the U tiling value and is not restricted to integers. Absolute and + relative are ignored.

Twist

Amount

Set the number of full revolutions to twist the material per V tile.

Random flip

Randomly flip the texture twist direction.

V

V coordinates run along the branch.

Style

Select the method used to compute V coordinates:

Property Description
Absolute V tiling is set explicitly.
Relative (Keep Aspect Ratio) V tiling is computed based on the U tiling and branch radius in such a way that the aspect ratio of the applied material is maintained.
Relative V tiling is computed based on the length of the branch.

Anchor

Select which end of the branch the V coordinates are computed from.

Property Description
Start V coordinates are computed from the start towards the end.
End V coordinates are computed from the end towards the start.

Scale

Control the amount of V tiling.

Skew correction

When the style is set to Relative (keep aspect ratio), this property controls how much of an attempt is made to fit the mapping to the changing radius of the branch. A value of 0.0 makes no correction. A value of 1.0 adjusts the V coordinates to accommodate branches that get narrower or wider. Use this property to avoid the appearance of stretched maps, especially as branches narrow near the end.

Pinch

Fine-tune V texture coordinates near the end of a branch when repeating or clamping artifacts are visible.

Offset

Shift V values by this amount.

Note: Use variance on this property to make branches each have a random start point for the V coordinates.

Materials

The properties in this group control the material assignments.

Branch

Apply a material to the branches in this generator. Use the button controls to add [+] or remove [-] materials per geometry type.

Material

Specify a named material from the Materials Bar, a named set from the Material Sets Bar, or use “Inherited” to pick up the material from the parent.

Weight

Set the probability that a node will receive this material index (this weight divided by the sum of all weights).

Note: Using multiple branch maps will require additional draw calls in real-time use.

Lightmap

Lightmap UVs are computed for several versions of the Modeler designed for use with game engines. Lightmap UVs are a UV set where no objects overlap and all of them fit in a single space where U and V fit in the range [0.0, 1.0].

Weight

This value influences how much space in the lightmap branches made by this generator can have.

Use the distribution curve to control where the lightmap UV density is applied. The default value packs more at the base than at the tip. Keep in mind that the weight value is considered along with the geometry area and texture area of the object.

In addition, every object's lightmap weight is compared to every other object and then the lightmap packing is determined. This means that your weight value may not be honored exactly or may get so large as to exhibit unexpected results. Use “Tools→Reset lightmap scalars” to go back to default values for the whole model.

Decorator

The properties in this group control how much of the parent is covered by the shell and how much wider the shell is than its parent.

Extension style

Set the behavior of any nodes applied to extensions.

Property Description
Automatic Compute the behavior based on the parent node.
Manual Set the behavior with the Position and Scale values.
None Remove nodes from extensions.

Position

Control how far up the parent the shell goes. 0.0 means cover none of it and 1.0 corresponds to fully covering the parent.

Note: You can use opacity maps on the shell material to allow the parent branch material to show through.

Scale

Control how much wider the shell is than the parent (in terms of the parent's radius). Use the profile curve to vary this value along the shell.