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TextureImporterSettings.spriteMeshType

public SpriteMeshType spriteMeshType;

Description

SpriteMeshType defines the type of Mesh that TextureImporter generates for a Sprite.

When SpriteMeshType.FullRect is specified, it will generate a rectangle Mesh equal to the user specified Sprite size.

When SpriteMeshType.Tight is specified, it will generate a tight Mesh based on pixel alpha values.