Packing in UV Flow Add-on

Packing in UV Flow Add-on#

The packing feature in the UV Flow add-on allows users to efficiently arrange UV islands within a specified UV space. This guide provides an overview of the packing options available and how to use them effectively.

Overview#

Packing can be performed directly from the Cut UV tool. The interface includes two main buttons:

  • Record Button: Toggles automatic packing after each action.

  • Play Button: Initiates packing when clicked.

Packing Options#

Include Options#

The Include section in the UV Flow pack menu determines which faces are packed together. The available options are:

  • Selected Faces: Packs all selected faces together.

  • Selected Objects: Packs all faces of the selected objects together.

  • Selected Materials: Packs all faces of every object in the scene that shares the same material as the selection (in Edit Mode) or the active material (in Object Mode).

Group Settings#

The Group setting specifies how islands are packed into the same UV space. You can choose from the following options:

  • All Islands Together: Packs all islands into a single UV space.

  • Objects Together: Packs islands based on their respective objects.

  • Materials Together: Packs islands based on shared materials.

Shape Settings#

The Shape setting controls the accuracy and speed of the packing process. The options include:

  • Bounds: The fastest option, treating each island as a simple rectangle.

  • Convex: Slower than Bounds, this option considers the outer shape of the island but does not support holes or concave features.

  • Concave: The slowest option, using the actual shape of the island for the most accurate packing.

Pack To Options#

The Pack To setting determines where your islands will be placed. The options are:

  • Closest UDIM: Places the island within the nearest UDIM.

  • Active UDIM: Packs the island into the currently active UDIM.

  • Bounding Box: Packs the island based on its bounding box before packing.

If UDIMs are not in use, the first two options will pack all islands into the default UV space (0 to 1).

Merge Overlapping#

The Merge Overlapping option allows overlapping islands to be packed as a single island. This is particularly useful when duplicated or mirrored UVs are laid directly on top of each other.

Lock Pinned#

The Lock Pinned feature controls how much your pinned UV islands are transformed during packing. This ensures that important UVs remain in place while others are adjusted.

Average Scale#

The Average Scale option applies an Average Island Scale operation to all UV islands before packing, ensuring that they share the same texel density.

Rotation Settings#

The Rotation setting determines how much each island is allowed to rotate during packing. The options include:

  • Full Rotation: Allows islands to rotate freely, resulting in a tighter pack but potentially skewed islands.

  • Cardinal: Restricts rotation to 90-degree increments.

  • Axis Aligned: Rotates islands to fit the smallest possible vertical or horizontal bounding box.

Margin Amount#

The Margin Amount controls the space between each UV island. It is recommended to maintain some margin to prevent pixel bleeding between islands. For applications that support Mip Mapping (e.g., most game engines), a margin of at least 1.6% is advised.

  • Fast Method: Quick to compute but provides a rough approximation.

  • Exact Method: Slower but ensures pixel-perfect padding.

Conclusion#

The packing feature in the UV Flow add-on provides a comprehensive set of tools for efficiently arranging UV islands. By understanding and utilizing the various options available, users can achieve optimal packing results tailored to their specific needs.

For further assistance or advanced techniques, please refer to the additional documentation or community forums.