Layout system for consistent user interface results

At least one computer-readable medium having computer-executable instructions, which when executed perform steps, comprising:

• at a layout system:
• receiving first data from a parent element directed towards a child element to provide the child element with an available size;
• applying policy to change the available size to an adjusted available size and providing the adjusted available size to the child element;
• receiving return data from the child element corresponding to a desired size;
• preserving the desired size;
• returning a return size corresponding to the available size to the parent element;
• receiving second data from a parent element directed towards a child element to provide the child element with an actual rendering area;
• changing the second data to provide an adjusted rendering area to the child based on policy and the preserved desired size;
• receiving a rendering size from the child based on the adjusting rendering area;
• and
• applying a transform and/or clip so that child output corresponding to rendered output in the adjusted rendering area fits in an area that corresponds to the actual rendering area.

In a computing environment, a system comprising:

• a parent element that directs calls to a child element;
• and
• a layout subsystem that receives calls from the parent element directed to the child element, including a measure call in a measure pass, to apply policy capable of adjusting an available size parameter set provided by the parent element for the child element so that the child element receives an adjusted available size parameter set;
• and
• the layout subsystem further receiving an arrange call in an arrange pass, to apply policy capable of adjusting an actual size parameter set provided by the parent element for the child element so that the child element receives an adjusted actual size parameter set, and the layout subsystem applying a transform and/or clip so that content output by the child element fits in a size that corresponds to the actual rendering area.