The Default Envelope permits the user to distort the contents of the envelope in a free form manner. All sides are treated as curves. The other Preset Envelope apply a specific shape to the contents as indicated by the icons.

Clicking on any corner produces Bezier control handles, which when dragged change the shape of the envelope and its contents in real time.

The Default Perspective Envelope treats all sides as straight lines and permits each corner to be manipulated separately. We will be working with the Default Perspective envelope.

The Default Perspective Envelope can be used to snap a panel to a perspective shape such as the rectangle in the back.

Select the object to which perspective is to be applied, then select the Mould Tool and press the Default Perspective Envelope button.

Press the Snap To Objects magnet icon on the Infobar.

Using the Mould Tool cursor, drag the corners of the object or objects, in this case the checkerboard, to the appropriate corner of the perspective rectangle until the corners snap onto the corner of the perspective rectangle.

When the corner of the selected object is dragged near a point to which it can snap, the cursor changes to a magnet indicating a snap.