HDevelop User's Manual

56 CHAPTER 2. GRAPHICAL USER INTERFACE
Clicking on a variable will select it. Similar to iconic variables, all program lines that use this
variable are then marked with a black rectangle on the left.
Double-clicking a control variable opens a window that displays all its values. In most cases
this will be a dialog containing a scrolled list. This is helpful if you have variables with a large
number of values that you want to inspect. In the case of a frame grabber handle, a dialog
Figure 2.37: Variable inspection for frame grabber handles.
representing basic frame grabber parameters is opened (see figure 2.37). Here you find the size,
name, device, port, and other features of the frame grabber. The toggle button ÇÒÐÒ allows to
grab images continuously and to display them in the active graphics window. If an error occurs
during grabbing, it is displayed in the status bar of the dialog. At most one of these frame
grabber dialogs can be opened at the same time.
2.7 Graphics Window
This window displays iconic data. It has the following properties:
¯ The user may open several graphics windows.
¯ The active graphics window is shown by the green dot in the ØÚ button.
¯ Pressing the ÐÖ button clears the graphics window content and the history of the
window.
¯ You close a graphics window using the close button of the window frame.
Figure 2.38 shows an example for a graphics window.
The the origin of the graphics window is the upper left corner with the coordinates (0,0). The x
values (column) increase from left to right, the y values increase from top to bottom. Normally,
HDevelop / 2000-11-16