Transform a shape using source and target reference triangles. The specifics of the transformation are encoded by the differences between the triangles.

Input parameters:

1. Sh → Optional shape to transform.
2. St → Triangle representing the initial state.
3. Tt → Triangle representing the final state.

Output parameters:

1. Sh → Transformed shape.
2. Tr → Transformation consisting of the translation, dilation, rotation and shearing required to go from the source to the target triangle.