### 3.5 Collapsing and Expanding ¶

Msc-generator allows you to collapse boxes, entity groups (signalling charts); blocks (block diagrams); and cluster subgraphs (graphviz graphs). This way you can show only a simplified view of the procedure, diagram or graph described by the chart text. E.g., instead of many arrows comprising a part of the procedure, a simple box is shown as a summary.

If you move the mouse over a chart element that can be collapsed (or is already collapsed), control icon(s) appear at its top right corner. The control with the minus sign collapses the element, the control with the plus sign expands a collapsed element, while the green arrow collapses the element into a block arrow. The last icon will only appear for boxes of signalling charts, which are not part of a box series (Drawing Boxes).

In the MFC GUI you can disable the showing of such controls via the red plus button on the Chart pane. This improves compilation time a bit.

For signalling charts and block diagrams expanding and collapsing can also be set via the ‘`collapsed`’ attribute (for group entities/boxes or blocks, respectively) and hence is available for the command-line version, as well. It is most useful, however, for interactive work. Any collapse/expand setting via the GUI overrides the one specified by attributes. Such overrides are saved with embedded charts, but naturally not when the chart is saved to disk as text.

In both GUIs, double clicking any element that has controls (can be collapsed/expanded) activates the first control (even if controls are not shown). This essentially toggles collapse/expand status.