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SimpleGraph

Click on the image for a live example

Most Catacomb graphs and diagrams allow zooming, panning and selecting regions with the mouse. A left click zooms in keeping the clicked point fixed. Clicks with the right button zoom out. Long clicks with the left button and clicks with the CTRL key held down also zoom out. Clicking to the left of or below the axes scale only that axis. Press-drag-release moves the data with the mouse. Pressing "f" with the mouse over the diagram recenters the data in the window.

While you can probably work out a fair bit of how to manipulate the graphs by trial and error, all the details are below. They use left and right buttons separately, try click-drag-release with different starting points - on the data, to left or right of the axes, etc. You can also click on the data drag the mouse off, and draw loops. Dragging diagonally and then back across the starting point starts a box cursor to select a region.

There is a small menu in the top right corner of each graph. From here you can recenter the data, change the display style, and keep an image of hte window in a new frame. The capital letters in the options indicate keyboard shortcuts which do the same. The mouse must be over the window when you press the key.

The scrollbars indicate the fraction of the useful display area currently visible, where useful is taken to mean the smallest box containing both the current view and all the data. So, for example, if the data is actually all to he left of the current range, the horizontal scrollbar will occupy the right half of its range, indicating that what you see is only the right part of a larger box which includes the data. The scrollbars can be dragged by the ends to change the scale of the graph, or by the center to pan the display. One consequence of the above definition of the "useful" area of the display is that if you drag the end of a scrollbar which is against the border, the bar will not shrink until the data begins to go out of the window.

zoom in, keeping the point under the mouse fixed	short click	Avoid active points on the graph, or these will take precedence.
zoom out, keeping the point under the mouse fixed	long (> 150 ms) click or click with right button	Avoid active points on the graph, or these will take precedence.
pan	left mouse: click, drag, release	the axes are shifted so the point on the data where you clicked moves to where you released the mouse button.
continuous pan	right mouse: click, drag, release	as above, can be slow if a lot of data is plotted
select a region with a box cursor	diagonal drag, away, and then across the desired box (see below)	Any corner will do as a starting point, but you must drag diagonally away for ten pixels or so, and then back past the original point before the box appears (otherwise the motion will be taken as panning).
continuous zoom, in or out	click the fixed point, drag the mouse off the window, and then draw loops	clockwise loops zoom in; anti-clockwise loops zoom out

Most of these are modified depending on where you click the mouse:

on the graph	rescale both axes
below the abscissa	rescale only the abscissa
to the left of the ordinate	rescale only the ordinate
above the graph (but still in its window)	rescale the background grid for the abscissa
to the right of the graph	rescale the background grid for the ordinate

Box cursors

To get a box cursor you click on one corner of the desired box, drag the mouse diagonally away from the opposite corner of the box you want and then back past your starting point to produce the cursor. For example, these mouse movements will initiate, and start to drag box cursors.

Zooming

To start continuous zooming, you must drag the mouse out of the box. Drawing clockwise/anti-clockwise loops then zooms in/out. For example, the movements on the left will zoom in and/or out.