On Tue, May 11, 2010 at 11:55:29PM -0500, Maurice LeBrun wrote: > > I agree, xor mode sucks big time (due to the line occasionally becoming > invisible). > > On a recent project, I implemented a plot overlay capability for drawing a > ruler between two interactively selected points, with coordinates plotted in > world coordinates. The basic flow was as follows: > > - set up all the event bindings to have the facility act as desired > - every time the mouse moves: > o force an expose event.. this blits the backing pixmap to the screen > o turn off plot buffer & backing pixmap writing > o draw your desired overlay & register it with your redraw facility (you must > commandeer redraw for this to work) > o turn back on plot buffer & backing pixmap writing > - restore original bindings when custom drawing mode is terminated > > The turning off of the plot buffer & backing pixmap writing requires some > rather evil direct manipulation of the contents of the PLStream and XwDev > structs.. an API for this would be hugely better. As well as a demo. One can > dream.. anyway maybe some food for thought.
I quite like this approach as it is more general than my idea for specifically dealing with selection rectangles. Any chance you could share your code for this? Andrew ------------------------------------------------------------------------------ _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
