The Aligning Tools mode provides all aligning and similarity related functionalities of the packer.
In order to use the Aligning Tools mode select it from the Main Mode selection menu:
The Aligning Tools mode provides two operations:
- Select Similar – selects all islands which have similar shape to at least one from the currently selected islands.
- Align Similar (Stack) – aligns the selected islands, so that islands which are similar are stacked on top of each other.
The most fundamental parameter, which drives the above operations is Similarity Mode - it defines the way in which the packer determines whether two UV islands are similar. The following modes are available:
- Border Shape
Two islands are considered similar, if shapes of their borders are similar. In this mode only the position of vertices which determine the island border are taken into consideration - the internal vertices and redundant border vertices are ignored.
- Vertex Position
Two islands are considered similar, if the number of vertices and their relative position match. In this mode the position of all island vertices are taken into account, but the island topology (how the vertices are connected to each other) is ignored.
Two islands are considered similar, if the number of vertices and their relative position match and also island topologies are the same. In this mode not only the position of all island vertices are taken into account, but also the island topology (how vertices are connected to each other).
Availability of the other parameters depend on which similarity mode is currently selected. Read below for details.
Border Shape parameters
The Border Shape mode supports the following set of parameters:
- Precision: more precision means better accuracy in looking for similar islands in the Border Shape mode. Precision set to 500 should be sufficient in most cases. This value should be increased in the first place, when dealing with really small islands.
- Similarity Threshold: a greater value of this parameter means island borders will be more likely recognized as similar in shape. A lower value means more accurate distinction.
Vertex Position and Topology parameters
Vertex Position and Topology modes support the same set of parameters:
- Correct Vertices - correct position of matching UV vertices of similar islands so they are placed on the top of each other after aligning. This option is only available when the Check Vertices option is enabled.
- Vertex Threshold - maximum distance below which two vertices are considered as matching.
Common parameters available for every similarity mode:
- Adjust Scale - when this option is enabled, the packer will scale islands to the same size before determining whether they are similar.
Topology mode considerations
The Topology mode is the most expensive mode from the computing and memory perspective, that is why it is not recommend to use it with UV islands with a huge number of vertices (10000 vertices or more). If you require aligning with vertex correction for such islands, use the Vertex Position mode first and switch to the Topology mode only if you didn’t receive desired results.
If you have to use the Topology mode for heavy UV islands, make sure the Vertex Threshold parameter is set to the lowest value which gives you the expected outcome.
By default you don’t have control over which island will be aligned to another, when two islands are considered similar by the packer. You can control this behaviour by enabling the Align Priority functionality.
Align Priority is a per-island integer parameter - you can assign a priority to every island in the UV map. When two islands are considered similar by the packer, then the island having a lower priority value will be aligned (moved) to the island with a greater priority value.
By default all islands will have priority 0 assigned.