To add, edit or delete source slots individually, use the Slot Editor... window which can be accessed from the Plaque menu or Window menu.
In this example the setup appearance window was used to render slots opaquely in order to make editing easier.
The Slot Editor... is best used in interactive combination with the Plaque window and the Setup window set to Plaque design wireframe mode (click the plaque construction icon near the upper right of the Setup window).
The origin of the plaque coordinate system in Plaque Simulator (PS) is the center of a sphere defined by the radius of curvature (R) of the plaque's inner (concave) surface. The concave surface is also referred to as the face of the plaque. In the Plaque window you are normally looking at the face of the plaque.
The Z axis of the plaque coordinate system is the central axis of the plaque. The default center of a linear source (eg I-125 seed) or a beta patch source (eg Ru-106) is tangent to a sphere of radius R' = R + Offset, with the Z axis passing through the center of the source at Z = -R'. The orientation of the linear source is parallel to the Y axis (Tilt = 0°). Plaque Simulator then uses the angle Alpha or its projection onto the XY plane, the distance r, and angles Beta and Tilt to rotate the source center away from its default location and orientation on the sphere. Sources remain tangent to the sphere. You can create a flat plaque by forcing sources to remain in a plane perpendicular to the Z axis by checking the Force Z button.
The currently selected slot is indicated by the popup menu in the toolbar at the top of the window. You can change the index ordering of the slots by selecting a slot and using the Fwd and Back buttons in the toolbar to rearrange its index. The radio buttons in the Editing options box select the data entry format: (alpha,beta,tilt) or (r,beta,tilt). Checkboxes enable hiliting of the selected slot in other windows. You can also change the hilite and slot placeholder color if you wish.
In the toolbar, each time you click the Add button a new source placeholder will be added at the center of the plaque. You can then adjust its coordinates or drag it in the Plaque window. The Delete 1 button deletes only the currently selected slot placeholder, Delete All deletes all of the slot placeholders.
The Misc. group box on the lower left displays the equivalent Cartesian coordinates of the source with respect to the plaque origin.
You can also interactively drag and rotate a slot by setting the cursor mode to drag in the Plaque window and clicking on the slot. The control, option, & command keys can also rotate the slot when dragging in the Plaque window.