
Re: Clippling of polygons within a defined region
Posted:
Aug 5, 1999 2:27 AM


In article <7o5ff4$rgt@smc.vnet.net>, Allan Hayes <hay@haystack.demon.co.uk> writes >John, > >The same problem arises with big points, thick lines and with text. >Here is an first attempt at dealing with it. > <Snip> > >One undesirable feature of this is that we are relying the hidden frame and >ticks in gr to make room for the versions in fat. > <Snip>
Thank you very much! That gives me exactly what I needed. At first I thought it was a complete solution but I now see what you mean about an "undesirable feature". There seems to be a small problem with FullGraphics in terms of the position and orientation of FrameLabels and PlotLabel (fortunately easy to overcome: before, I had absolutely nothing!).
*************example******************** In[1]:= Masked[gr_Graphics, st___] := Module[{fat, pr, mask, e, x1, x2, y1,y2}, (*get the explicit graphics for frame, and frameticks*) fat = Delete[FullGraphics[gr], {1, 1}]; (*get the explicit plotrange for gt*) {{x1, x2}, {y1, y2}} = pr = PlotRange[gr]; (*calculate a suitable mask with style st*) e = Max[x2  x1, y2  y1]; mask = Graphics[{st, Polygon[{{x1, y1}, {x2, y1}, {x2, y2}, {x1, y2}, {x1, y1}, {x1  e, y1  e}, {x1  e, y2 + e}, {x2 + e, y2 + e}, {x2 + e, y1  e}, {x1  e, y1  e}}]}]; (*show the graphics in the right order*) Show[gr, mask, fat, PlotRange > pr]]
In[2]:= gr2 = Show[ Graphics[{Polygon[{{1, 0}, {2, 2}, {2, 1}}], PointSize[0.5],Point[{1, 1}]}], Frame > True, FrameTicks > True, PlotRange > {{0, 1}, {0, 1}}, FrameLabel > {"X Axis", "Y Axis"}, PlotLabel > "Plot Label"]
In[3]:= Masked[gr2, RGBColor[1, 1, 1]]
In[4]:= Select[ToString[#] & /@ Flatten[FullGraphics[gr2] /. Graphics > List], StringPosition[#, "Axis"] =!= {} &]
Out[4]= {"Text[X Axis, {0.5, 0.0202254}, {0., 1.}]", "Text[Y Axis, {0.01875, 0.5}, {1., 0.}]"} ****************************************
This seems to show that Text is being called with 3 arguments, missing the "offset" argument in position 3.
Incidentally, the behaviour of Display in generating output files is rather different from Show. I still do not fully understand the following, but it appears that the FrameLabel added by the Masked function overrides the previous Text calls etc., completely the opposite to the behaviour of Show. The new Export command does give the same as Show.
**************************************** In[5]:= Display["c:\\temp\\tmp1.gif", gr2, "GIF"]
In[6]:= Display["c:\\temp\\tmp2.gif", Masked[gr2, RGBColor[1, 1, 1]], "GIF"]
In[7]:= Select[ToString[#] & /@ Flatten[Masked[gr2, RGBColor[1, 1, 1]] /. Graphics > List], StringPosition[#, "Axis"] =!= {} &]
Out[7]= {"Text[X Axis, {0.5, 0.0202254}, {0., 1.}]", "Text[Y Axis, {0.01875, 0.5}, {1., 0.}]", "FrameLabel > {X Axis, Y Axis}"} ****************************************
Thank you again! This saved me much time.
John.

