2.11 Selecting Objects

Many Visual commands require that objects within the lighting model be selected either for modification or reference. Generally speaking, these commands may be applied to objects either individually, or in groups. The process typically consists of object selection followed by the specification of any information necessary to complete the particular command. Because the object selection process is a common occurrence, Visual incorporates a consistent routine for the sake of simplicity.

Upon initiating any command involving object selection, the Status bar will prompt for the selection of objects. For example, the Move command at right.
The mouse crosshairs will temporarily change to a pick-box indicating that Visual is using the Pick selection method. To select Background objects, Solid objects, and Calculation Zones, simply place the pick-box over any element of the desired object and left-click the mouse.
In Transparent and Rendered Display Modes, Visual allows both the perimeter and interior of Solid Objects to be clicked to indicate selection.
The object will turn the selection color (the system default is red, but can be user-modified in Environment Settings) to indicate that it is selected. If more than one object is in the pick-box area then only a single object will be selected. To toggle through the objects under the pick-box simply left-click the mouse again and the next object will be selected while the previous object will be unselected. Continue clicking until the desired object is selected.

The selection order of objects is based on the Z-order. This means that the object closest to the camera is selected first. If a second click is made on visually coincident objects, the next farthest object will be selected, and so on. For example, in a Top View, when clicking as in the above example, the object selected would be the "ceiling", a second click in the same spot would select the "wall" below, and a third click would select the "floor". If a fourth click where made, the cycle is completed by the "ceiling" being the selected object again.

In Transparent, Shaded, or Rendered display mode, Solid objects can be selected by clicking on any part of the surface. In Wireframe display mode, a bounding edge must be clicked.

Moving to the right after the first left-click creates a rectangle with a solid border and light blue shading, indicating the Window selection method. When using the Window selection method, any object that resides entirely within the window will be selected. In the example at right, the square is fully contained and the triangle and circle are not; thus only the square is made part of the selection set.
Moving to the left after the first click creates a rectangle with a dashed border and a light green shading, indicating the Fence selection method. When using the Fence selection method, objects having any portion within the fence will be selected. In the example at right, the triangle is fully contained, the square is not contained, and the fence crosses the circle; thus the triangle and the circle are made part of the selection set.
The Properties tab will include the Selection panel to assist in selecting objects for Modify tab commands. Visual defaults to adding clicked objects to the selection set, signified by the Add Selection button being highlighted in yellow.
The Properties tab will include the Object Filters panel to assist in selecting objects for Modify tab commands and other times when objection selection is required; e.g. specifying a surface on which to place a Calculation Zone. A checkbox is present for each of the four object types. Unchecking a box tells Visual to ignore objects of that type when selecting objects.
As both an example of Object Filters and a usage tip: Power Zones and Calculation Zones are often created such that they are coplanar. When selecting either type for modification, it is likely to be unclear which zone type has been selected. To be sure which is selected, change to Transparent Display Mode. Secondly, use the Object Filters to remove Solids. This allows selection of a calculation point to select a Calculation Zone or simply selecting "empty space" as shown at far right to select the coplanar Power Zone. (This example is selecting first the Calculation Zone and alternately the Power Zone.)
The selection process also allows objects to be removed from the selection set. To toggle to the Remove selection mode, press the Remove Selection button or press the R key on the keyboard while the pick-box is active.
In addition to the Remove Selection button being highlighted in yellow, the Status bar will also indicate that the subsequently selected items will be removed from the current selection set.
Click the Add Selection button or press the A key to return to the Add selection mode if necessary.
Clicking the Select All button selects all objects in the Design Environment. Pressing the L key while in selection mode also causes all objects to be selected.
Clicking the Previous Selection button or pressing the P key while in selection mode causes objects previously selected (in the last command executed) to be selected again for use in the currently active command.
The Pick, Window, and Fence methods can be used repeatedly in both Add and Remove modes until the selection set contains only the desired objects. The process is terminated with a right-click of the mouse, and Visual ends the command or moves to the next step in the command depending on the command executed.

Command-specific information about selecting objects is found later in the manual where necessary.