The Transform Tool allows you to geometrically transform the currently selected image layer.
You can choose between three different modes:
- Scaling only
- Stretch (independent vertical and horizontal scaling)
- Free or Perspective transform
The transform operation is defined by a transform cage. To change the transform cage, you can drag it's edge and side handles. When using non-free transform, the edges not currently moved are adjusted accordingly to satisfy the selected geometric constraints.
Drag inside the transform cage to move.
Drag outside of the transform cage to rotate. The rotation center is defined by the central rotation center handle.
For most arbitrary transformations, no mapping exists that maps exactly one input pixel to exactly one output pixel. To fill in unknown colors, interpolation is needed. PencilSheep supports four interpolation methods:
- "Point" simply chooses the color of the nearest input pixel.
- "Linear" mixes the four closest input pixels around the current output pixel.
- "Cubic" looks at 16 input pixels around the current output pixel and also takes into account shape.
- "Soft" works in a similar way as "Cubic", but produces smoother although slightly blurred results.