gl2 now has glrgba cmd for alpha channel. plot is also too complicated for me to follow. If you want to hack, then search for all those 2032 which means glrgb and change them to 2343 (glrgba). Of course life is not that easy, but this should be a starting point. On Jun 27, 2015 12:31 PM, "June Kim (김창준)" <[email protected]> wrote:
> Hello > > Years ago, I asked about using alpha channels in plot. Bill Lam showed one > way of possibility. > > I have used a different tool(R's ggplot) then. Now I am looking into J's > plot again. Is there any simple way to add transparency in plot? I have > explored the source code for a while but it was just too complicated. > > Maybe, something like the following would be ideal, > > pd 'color 255 0 0 100' NB. RGBA > pd i.10 > pd 'show' > > Any ideas? > > On Sun, May 13, 2012 at 1:39 PM, bill lam <[email protected]> wrote: > > > As a very crude way to demostrate alpha channel in jgtk, open the > > file ~addons/graphics/gl2/gl2.ijs , find the verb irgba2cairo > > > > irgba2cairo=: 3 : 0 > > 'r g b a'=. 255%~ 4{.y,0 > > a=. 1-a > > (r,g,b), a > > ) > > change the the 'a=. 1-a' to > > > > a=. 0.5 [ 1-a > > > > then open the config base.cfg, change the noun GL2ExtGlcmd to 0. > > restart J and try some gkt plot. > > > > Вск, 13 Май 2012, bill lam писал(а): > > > plot depends gl2 and gl2 does not yet support alpha channel. The main > > > difficulty is to decide alpha to mean opacity or translucence. One > > > of them is incompatible with the old gl2 while the other is > incompatible > > > with cairo, iirc. > > > > > > Вск, 13 Май 2012, June Kim (김창준) писал(а): > > > > Hello > > > > > > > > Is there any way to use the alpha channel in plot(in J7 or J602)? > > > > http://en.wikipedia.org/wiki/RGBA_color_space > > > > > > > > The thing is I will draw a lot of overlapped line plots and if the > > lines > > > > are a bit transparent it would look much easier to see the patterns. > > > > > ---------------------------------------------------------------------- > > > > For information about J forums see > http://www.jsoftware.com/forums.htm > > > > > > -- > > > regards, > > > ==================================================== > > > GPG key 1024D/4434BAB3 2008-08-24 > > > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > > > > -- > > regards, > > ==================================================== > > GPG key 1024D/4434BAB3 2008-08-24 > > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
