Re: Lost Line Directives in 3D Graphics
- To: mathgroup at smc.vnet.net
- Subject: [mg30136] Re: Lost Line Directives in 3D Graphics
- From: "Allan Hayes" <hay at haystack.demon.co.uk>
- Date: Tue, 31 Jul 2001 04:27:10 -0400 (EDT)
- References: <9k2d95$2ds$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
David, I am getting the same as you with Version: "4.1 for Microsoft Windows (November 2, 2000)" Machine: Toshiba Tecra 750 DVD Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 -- Allan --------------------- Allan Hayes Mathematica Training and Consulting Leicester UK www.haystack.demon.co.uk hay at haystack.demon.co.uk Voice: +44 (0)116 271 4198 Fax: +44 (0)870 164 0565 "David Park" <djmp at earthlink.net> wrote in message news:9k2d95$2ds$1 at smc.vnet.net... > Dear MathGroup, > > Here is a case where it appears that Mathematica incorrectly renders the > postscript code for Graphics3D. I wonder if other people obtain the same > effect that I obtain. > > Needs["Graphics`Animation`"] > > grafs = {Line[{{0, 0, 0}, {2, 0, 0}}], RGBColor[1.`, 0.`, 0.`], > AbsoluteThickness[ > 4], {Line[{{0, 0, 0}, {0.999`, 0, > 0}}], {Polygon[{{1.`, 0.`, 0.`}, {0.6666666666666667`, 0.`, > 0.16666666666666666`}, {0.6666666666666667`, \ > -0.14433756729740643`, -0.08333333333333333`}}], > Polygon[{{1.`, 0.`, > 0.`}, {0.6666666666666667`, -0.14433756729740643`, \ > -0.08333333333333333`}, {0.6666666666666667`, > 0.14433756729740643`, -0.08333333333333333`}}], > Polygon[{{1.`, 0.`, 0.`}, {0.6666666666666667`, > 0.14433756729740643`, -0.08333333333333333`}, \ > {0.6666666666666667`, 0.`, 0.16666666666666666`}}]}}}; > > plot1 = Show[Graphics3D[grafs], PlotRange -> > {{-1, 1}, {-1, 1}, {-1, 1}}*2, ImageSize -> 500, Boxed -> False]; > > > The plot consists of a long thin black line, and a shorter thick red line on > top of it, with a three polygon cone at the end, but slightly detached from > the short line. The line directives for the short line are lost, so that it > also appears thin and black. > > But if we SpinShow the plot we see that in 4 out of 24 frames the line > directives are not lost. I don't understand postscript rendering of > graphics, but if we select the good frames and bad frames and use > Shift-Ctrl-E to look at the postscript code, we can see that there is a > definite difference between the frames. The good frames have some extra > code, including Mabswid commands. > > SpinShow[plot1]; > > If the first line is moved just a little off the direction of the short > line, then the problem does not occur. The second line has to be on top of > the first line, and the polygons must also be present for the error to > occur. > > grafs2 = {Line[{{0, 0, 0}, {2, 0, 0}}], RGBColor[1.`, 0.`, 0.`], > AbsoluteThickness[4], {Line[{{0, 0, 0}, {0.999`, 0, 0}}]}}; > > plot2 = Show[Graphics3D[grafs2], PlotRange -> > {{-1, 1}, {-1, 1}, {-1, 1}}*2, ImageSize -> 500, Boxed -> False]; > > David Park > djmp at earthlink.net > http://home.earthlink.net/~djmp/ > >