The Spine Influence modifier creates a soft selection of spline knots based on their proximity to the origin of the specified objects.
The selection of individual knots is shown in the viewports as a color gradient ranging from red (completely selected) to blue (not selected).
Interface
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Influence Parameters rollout
- Influences list
- Shows a list of objects currently influencing the spline knot selections.
- Pick button
- Selects objects by clicking directly in the viewport.
- Add button
- Opens a Scene Explorer dialog to select objects.
- Delete button
- Deletes selected objects from the Influences list.
- Near Distance
- Sets the distance for 100% selection of the knot. Knots which are this distance or closer will be selected.
- Far Distance
- Sets the distance at which knots are not selected. Knots which are this distance or further will have no selection applied.
- Falloff Type
- Sets the type of falloff between the Near and Far distance settings. The Smooth and Smoother options improve blending quality however require more processing.
- Apply Bias
- Adds a specific value to the selection amount. For example, a value of 0.25 adds an additional 25% to the selection value.
- Amount
- Sets the amount of bias to add.
- Only When Selected
- Sets the bias to be added only if the selection value is greater than 0.
Existing Selection Values group
- Add
- If knots are already selected by prior operations in the modifier stack, this option adds the two values.
- Multiply
- If knots are already selected by prior operations in the modifier stack, this option multiplies the two values.
- Overwrite
- Replaces existing selection values with this selection.
Selection Modify group
Use these settings to convert existing knot selections into soft selections before performing object proximity selections.
Note: Knot selections are additive to neighbouring selections.
- Convert Selections
- Converts selected knots into soft selections.
- No Falloff
- Converts each knot selection to 100%.
- Percentage of Length
- Sets the percentage of the spline's length that the falloff will go from 100% to 0%. For example, if the value is 50%, then a selected knot will taper off its selection to 0% at half the distance of the spline.
- Neighbor Knots
- Sets a specific number of knots ranging from 100% to 0%. For example, if the value is 5, the first knot will be 100%, its neighbour will be 80%, the third 60%, the fourth 40%, and the last knot 20%.
- Falloff Type
- Specifies the type of falloff to apply. The Smooth and Smoother options improve blending quality however require more processing.
- Invert Final Result
- Inverts the final selection. For example, a 100% selected knot becomes 0%, and a 70% selected knot becomes 30%.