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
>
>
>
>