Limits
The limit is a rectangular area to which the graphic representation on the screen and thus the accessibility of objects is restricted. The corners of the limits are specified on menu Options|Limits. Specify the coordinates of the bottom left and top right corners. The default values cover one square kilometer:
- bottom left corner: (x, y) = (0, 0) m
- top right corner: (x, y) = (1000, 1000) m
The limits may be edited at any time.
dialog Limits
Background color outside the Limits
The background of the limits is the area outside the specified limits. The default color is grey. The background color can be changed via menu Options|Miscellaneous.
Calc Limits
In order to recalculate for the limits when objects are lying outside, click the „Calc“ button on the dialog. The limits will then be adapted to comprise all objects. Afterwards, the dialog Limits displays the coordinates of the updated limits.
Scroll Bars
Calculations can be restricted to shielding objects only (buildings and barriers) within the limits. If, for the currently selected scale, the limits extend beyond the area represented on the screen, scroll bars will be shown at the bottom and/or right sides of the window. These serve to position the visible area within the limits. If the limits do not extend beyond the area visible on the screen, the scroll bars will be hidden.
Drag Graphic
Instead of adjusting the sector of the graphic with the scroll bars you can also drag the graphic representation, with the mouse key pressed, like a sheet of paper, freely to all sides. With the mouse key pressed on a free area in the graphic the mouse cursor changes to a mouse pointer looking like a hand. In this mode you can move the representation accordingly.
Update during Drag
With the option „Update during Drag“ on dialog Options|Miscellaneous activated the graphic is either built up continuously while moving the representation, otherwise just after releasing the mouse button.
Information on the Status Bar
The coordinates of the mouse pointer are displayed continuously on the right of the status bar of the CadnaA main window. After a grid calculation, the status bar will also display the levels (L) and the ground height (G) at the location of the mouse pointer.
Objects outside the limits
Sources lying outside the limits are also considered in the calculation. Obstacles that lie outside the limits, however, are not automatically considered in the calculation. In this case, a warning message will appear.
| Ignore | causes the objects outside the limits to be disregarded in the calculation |
|---|---|
| Repeat | results in the limits being modified so as to comprise all objects |
| Cancel | aborts the calculation |
How find objects outside the limits
After import of objects with unknown coordinates, depending on the import format used (see Import Formats), the limits are updated automatically in order to display all objects on the screen. This may, however, lead to extreme oversized limits if the imported objects are in a different coordinate system than the existing ones. In this case, it may be necessary to find those objects which have been - previously - outside the limits.
Proceed as follows:
- Draw section (or any other closed polygon) at borders of the actual limits.
- Recalc limits (via Options|Limits menu).
- Use command Modify Objects from context menu of that section or polygon.
- Convert all objects outside the polygon - for example - into railways (assuming there are no railways in the project file).
- Check via railway table using button „Sync. Graphic“ where these objects are located and whether they are relevant or not.
- In order to delete those objects, apply afterwards the command Modify Objects, action „Delete“, from context menu of that section or polygon.