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This panel appears in the Editing Context panel group which is accessed using F9 or clicking button in the Buttons window.UV Calculation Panel

[edit] UV Calculation

This panel appears when a mesh is being edited, and controls the unwrap process.

• Calculation Method

Angle-Based - unwraps by following faces until the angle of the face causes a 'break' which results in an island.

Conformal - tries to unfold the object by conforming it to the shape or method selected

• Fill Holes - Tries to arragne the UV islands so that large holes in the UV Texture (image space) are filled with a UV face
• Cube Size - When the Cube Projection unwrap method is used, the percentage of image space that will be used by the UV map.
• Cyl Radius - When a Cylinder from View unwrap method is used, the relative radius to height of the UV map ratio. If the object is 1.0 Blender units in radius, and this setting is 2.0, then the unwrap produces a squat unwrap.
• View Aligns Face - When unwrap "from view", the 3D view looks at the side of the object
• VA Top - When unwrap "from view", the view looks at the top, not the side, of the object
• Al Obj - Use the object's alignment axis and ignore the 3D View orientation
• Polar ZX - when an unwrap method is used that is not "from view", this selection says that the plane or orientation that is aligned with the ZX plane ("Front" 3D view) is the front.
• Polar ZY -the ZX plane ("Side" 3D View) is the front