Re: Manipulate is sluggish?

*To*: mathgroup at smc.vnet.net*Subject*: [mg83650] Re: Manipulate is sluggish?*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Tue, 27 Nov 2007 06:13:25 -0500 (EST)*References*: <fie1e7$t9b$1@smc.vnet.net>

Hi, you are sure that you need RGBColor@@cmyk2rgb[c,m,y,k] and not the build in version ToColor[CMYKColor[c, m, y, k], RGBColor] ?? Or do you just want to show that you conversion is wrong ? Regards Jens Tom Burton wrote: > Forgive me if this issue has been addressed. > > I'll soon need to work in CMYK colors and also will want to use the > new Manipulate expressions to visualize functions of 4 and 5 > variables. I decided to try a bit of both, first defining a > conversion from CMYK to RGB, > > cmyk2rgb[c_,m_,y_,k_]:=(1-k){1-c,1-m,1-y} > > and then comparing the two color systems: > > Manipulate[GraphicsGrid[Table[c=xx/12;m=yy/12;Graphics[{CMYKColor > [c,m,y,k],Disk[{xx,yy},1,{0,\[Pi]}],RGBColor@@cmyk2rgb[c,m,y,k],Disk > [{xx,yy},1,{\[Pi],2\[Pi]}]},ContentSelectable->False],{xx,0,12,2},{yy, > 0,12,2}]],{y,0.0,1,1/6},{k,0.0,1,1/6}] > > The expression above lays out a grid in cyan and magenta, with yellow > and black controlled by sliders. If my conversion algorithm is > wrong, corrections are welcome but beside the point I'm trying to > make, which is that the resulting dynamic graphic is sluggish and shy > on both my G4 dual 1G and my MacBookPro dual 2.3G. Response is so > slow that animation is always out of sync. After I manually move a > slider, sometimes I need to scroll the graphic completely off the > page and/or (???) focus on another cell in order for the graphic to > update. In other words, it won't update while I look at it (shy!). > The kernel will toil away at 90+% of one CPU indefinitely until I > scroll away and do something else. This behavior makes the graphic > nearly useless. It seems not to matter whether I use continuous > sliders, discrete sliders, or drop-down lists of fixed values. > > It's annoying to compare this sluggishness with the speed of the > corresponding movie in version 5.2: > > Flatten[Table[ > Show@GraphicsArray[ > Table[c=xx/12;m=yy/12; > Graphics[{CMYKColor[c,m,y,k],Disk[{xx,yy},1,{0,\[Pi]}], > RGBColor@@cmyk2rgb[c,m,y,k],Disk[{xx,yy},1,{\[Pi],2\ > [Pi]}]}, > AspectRatio\[Rule]1],{xx,0,12,2},{yy,0,12,2}],ImageSize\ > [Rule]500, > PlotLabel\[Rule]ToString[{y,k}]],{y,0.,1.01,1/6},{k, > 0.,1.01,1/6}]] > > This is not as slick and convenient as Manipulate in version 6, but > it's so much faster! Does anyone else see this sluggishness and > shyness? More importantly, can I work around it somehow? By the way, > the speed of graphics itself seems not to be the issue. The following > composite graphic of all slider settings is computed and displayed a > few seconds: > > GraphicsGrid[Table[GraphicsGrid[Table[c=xx/12;m=yy/12;Graphics > [{CMYKColor[c,m,y,k],Disk[{xx,yy},1,{0,\[Pi]}],RGBColor@@cmyk2rgb > [c,m,y,k],Disk[{xx,yy},1,{\[Pi],2\[Pi]}]}],{xx,0,12,2},{yy,0,12,2}]], > {y,0.,1.01,1/6},{k,0.,1.01,1/6}],ImageSize->800] > > Thanks in advance, > > Tom > > When responding, please replace news with my first initial and full > last name, as one word. > > Tom Burton > > > >