Tinker Toys Object Control Win Matrix Win View Control Win 

Vertex Window

The Vertex Window is used to examine a single vertex. The vertex's locations in the world-coordinate system, viewing-reference coordinate system and View Window Panel are displayed along with the equations that were used to calculate them. The Vertex Window is best used in conjunction with the Matrix Window, which will display the composite transform matrices referenced in the equations.

The first line of text shows the name of the vertex that is being examined. The vertex may be changed by clicking on a different vertex of the model in the World or View Window Panels.

The vertex's location in each of the following coordinate systems is then shown:

• The world-coordinate (WC) system: The current WC location of the vertex is generated by applying the model last transform matrix to the vertex's previous WC location, if any.
  
  
• The viewing-reference coordinate (VRC) system: The vertex's VRC location is determined by applying the view-orientation matrix to its WC position. The contents of the view-orientation matrix will be displayed in the Matrix Window when the mouse is clicked in the background of the View Window Panel.
  
  
• The two-dimensional view window coordinate system: If the current projection is parallel, the vertex's position in view window coordinates is set to the U and V components of the vector that is created by applying the shear-parallel matrix to the vertex's VRC position. The shear-parallel matrix will be displayed along with the view-orientation matrix in the Matrix Window if the projection is parallel.
  
  If the current projection is perspective, the view window coordinate position of each vertex is related to its (u, v, n) distance from the PRP and must be calculated individually. Calculations for both the U and V components are shown.

If the vertex has been clipped and thus is not displayed in the View Window Panel, a message to this effect will be displayed in the Vertex Window.

Menus

• File
  • Exit: Remove the Vertex Window from the screen. It may be redisplayed if it has been removed, but only one instance may exist at any given time.