2.3.8  Control Panel

Using the Control Panel, you can change major system parameters even during simulation. The program can be in two main states: Edit state or Simulation state. These are described in detail in the section Program states.

Computing body path elements are made by a program segment running on other thread. Upon refreshing the screen, this is suitable to reckon with changes to control panel parameters, if any. However, in Edit state only one thread running, when an internal Windows timer is used by the control panel for changes to be continually evaluated and refreshed. The Windows timer sends a message to the control panel in every 10 milliseconds (100 times in a second), i.e. the control panel text field and the main window background are refreshed in every such time.

Controls are contained in Table 7:

Table 7. Control Panel elements

Four pages of the Control Panel are shown in Figure 10, Figure 11, Figure 12 and Figure 13:

2.3.8.1  Select parameter

There are twelve radio buttons to select the system parameter to be changed. The value will immediately appear in the text field (see Change parameter selected). On selecting the velocity and force vectors, they automatically become visible. The Simulation speed changes linearly the Time unit, the Screen refresh time and the Simulation length simultaneously.

2.3.8.2  Change parameter selected

The edit control, slide and change ratio are to change the parameter selected.

Values entered in the text field are refreshed, when the focus leaves this field, e.g. if the parameter is selected again.

By using the slide, the parameter can be continuously increased or reduced so that change ratio depends on the distance of moving the slide off from the center and on the change ratio. The slide ranges from 50 to -50 in 101 different values that are confirmed by the numbers next to the slide. The default value is 0 in the middle of the slide. When the slide is moved off by using the mouse, the parameter value will change continuously, and when the mouse button is released, the slide will get back to 0 value and change will stop. If the slide is moved to +10, the parameter change, the change ratio times 10.

Change ratio ranges from 1 to 9 with its default value of 3. The higher the change ratio is, the finer the parameter change will be by moving the slide to the same extent. If you want to change parameter quickly, then the change ratio shall be low, if slowly, then the change ratio shall be high.

2.3.8.3  Visibility

Switching on/off system parameters to make visible change can be in these switches. Switching on/off Trail is visible on the screen only during simulation.

See further the section System.

2.3.8.4  Switches

These are switches to switch on/off Warning, Logging, On-Screen Information, Center of the coordinate system, ToolBar and StatusBar also influencing the rate of simulation.

2.3.8.5  Motion

Simulation is controlled by the switches as follows:

• Start or stop
• Start one step or stop
• Repeat switch on/off
   

2.3.8.6  Commands

Giving a command is immediately effected during simulation as well. Refresh will redraw, Repaint will delete and redraw the screen, Go Center will set the origin of coordinates into the screen center.

The B:, S: and I: will set the Background, selection and information color, Group will set the name and color of the Groups, and Bookmark will set the name of the Bookmark. The Add bookmark is to add a new bookmark to the others (see sections of Edit bookmark and Bookmark). The View will show the state of a bookmark.