On 2009-07-29 21:20+0200 Werner Smekal wrote: > Hi Alan, > >> I would also like to specify the transparency of the background >> conveniently >> using the -bg command-line option. I was thinking along the lines of >> >> -bg ff0000_0.3 >> >> to specify the same semitransparent background that I gave as an example >> above. The implementation would simply check the length of the option >> string >> and if greater than 6, parse the first 6 as hex, check for the underscore, >> and parse the remainder as a floating point value. Please comment _soon_ >> if >> you forsee any trouble with that implementation idea. > > I don't see any trouble, but what about > > -bg ff0000 > > for opaque and > > -bg ff00003f > > for transparent background. This would be much easier to check (must be 6 or > 8 chars) and transparency has most of the times 255 values anyway AFAIK > (depending on the implementation, e.g. png). > > But you solution would be also ok.
Thanks for your bringing up the possibility of an 8-bit representation for the command-line value of alpha. That would certainly work, but I prefer the command-line values be consistent with the cmap0 related PLplot commands which use 8-bit representations of rgb, and a floating representation of the alpha value. Alan __________________________ Alan W. Irwin Astronomical research affiliation with Department of Physics and Astronomy, University of Victoria (astrowww.phys.uvic.ca). Programming affiliations with the FreeEOS equation-of-state implementation for stellar interiors (freeeos.sf.net); PLplot scientific plotting software package (plplot.org); the libLASi project (unifont.org/lasi); the Loads of Linux Links project (loll.sf.net); and the Linux Brochure Project (lbproject.sf.net). __________________________ Linux-powered Science __________________________ ------------------------------------------------------------------------------ Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day trial. Simplify your report design, integration and deployment - and focus on what you do best, core application coding. Discover what's new with Crystal Reports now. http://p.sf.net/sfu/bobj-july _______________________________________________ Plplot-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/plplot-devel
