The BuildTransform method constructs a transformation matrix for a UI panel based on the specified width, height, and perspective origin. This method is part of the PanelTransform struct in the Sandbox.UI namespace. It is used to create a transformation matrix that can be applied to UI elements to achieve various visual effects such as scaling, rotation, and perspective transformations.

To use the BuildTransform method, you need to provide the width and height of the panel as float values, and a Vector2 representing the perspective origin. The method returns a Matrix that represents the transformation.

Example usage:

PanelTransform panelTransform = new PanelTransform();
Matrix transformMatrix = panelTransform.BuildTransform(500.0f, 300.0f, new Vector2(0.5f, 0.5f));

In this example, a transformation matrix is created for a panel with a width of 500 units, a height of 300 units, and a perspective origin at the center (0.5, 0.5).