On Wednesday, May 12, 2010 at 20:18:40 (+0100) Andrew Ross writes: > 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?
I'd have to essentially reimplement it from memory.. no time. On the great pile of projects I'd like to get around to. -- Maurice LeBrun ------------------------------------------------------------------------------ _______________________________________________ Plplot-devel mailing list Plplot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/plplot-devel
