# vanishing polyhedra on difference?

6 messages
Open this post in threaded view
|

## vanishing polyhedra on difference?

 Hello,so my previous question was stupid enough :D so i went into looking to achieve the desired result directly by using the polyhedrons, and here's the next dumb question:if you activate the difference on line 36, everything vanishes :(why?? (same for union BTW....)l = 3;dlu = 1.4;dlo = 2.9;w= 30;h= 11.5;uo = 9;uxo = 25;uxu = 27;module einschubForm(untereBr,obereBr,absend,absanf,abshoehe,hoehe,breite){  obVerjBreite = (obereBr-untereBr)*abshoehe/hoehe+untereBr;  polyhedron(      points=[[-untereBr,0,0], [untereBr,0,0], [untereBr,breite,0], [-untereBr,breite,0], //unteres Rechteck       [-obereBr,0,hoehe],[obereBr,0,hoehe], [obVerjBreite,breite,abshoehe],[-obVerjBreite,breite,abshoehe]    //oberes Rechteck      ,[-obVerjBreite,absanf,hoehe], [-obVerjBreite,absend, abshoehe], [obVerjBreite,absend, abshoehe], [obVerjBreite,absanf,hoehe] //Absenkung      ,[-untereBr,absanf,0], [-untereBr,absend, 0], [untereBr,absend, 0], [untereBr,absanf,0]      ],        faces=[      [0,3,2,1], //unten      [5,4,0,1], //stirn links      [1,2,6,10,11,5], //hinten      [2,3,7,6], //stirn rechts       [0,4,8,9,7,3], //vorne      [4,5,11,8], [8,11,10,9], [9,10,6,7]  //oben      ]      );}posx = 11.1;posy = 0;posz = 1.71;translate([posx,posy,posz]){  //difference()  //{    einschubForm(dlu,dlo,uxu,uxo,uo,h,w);    color("blue") translate([1,1.5,1])scale(v = [1, .9, .8]) einschubForm(dlu,dlo,uxu,uxo,uo,h,w);  //}}-- ciaoBruno===========================================http://nohkumado.eu/, http://aikido.nohkumado.eu/, http://aikido.zorn.free.fr _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|

## Re: vanishing polyhedra on difference?

 On 20.07.19 17:32, Bruno Boettcher wrote: > if you activate the difference on line 36, everything vanishes :( > why?? (same for union BTW....) The polyhedron is inside out, all faces have the points listed in reverse order. See: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/FAQ#Why_is_my_model_showing_up_with_F5_but_not_F6? ciao,   Torsten. _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org -- Torsten
Open this post in threaded view
|

## Re: vanishing polyhedra on difference?

 I did some experimenting with that, as long as it is consistent, openscad does the right thing. Not sure if the two polyhedra need to be consistent with each other though On Sat, 20 Jul 2019, 11:48 Torsten Paul, <[hidden email]> wrote:On 20.07.19 17:32, Bruno Boettcher wrote: > if you activate the difference on line 36, everything vanishes :( > why?? (same for union BTW....) The polyhedron is inside out, all faces have the points listed in reverse order. See: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/FAQ#Why_is_my_model_showing_up_with_F5_but_not_F6? ciao,   Torsten. _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org
Open this post in threaded view
|

## Re: vanishing polyhedra on difference?

 In reply to this post by tp3 ok! thanks!heh, understood the doc inversely....ciaoBrunoAm Sa., 20. Juli 2019 um 17:48 Uhr schrieb Torsten Paul <[hidden email]>:On 20.07.19 17:32, Bruno Boettcher wrote: > if you activate the difference on line 36, everything vanishes :( > why?? (same for union BTW....) The polyhedron is inside out, all faces have the points listed in reverse order. See: https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/FAQ#Why_is_my_model_showing_up_with_F5_but_not_F6? ciao,   Torsten. _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org -- ciaoBruno===========================================http://nohkumado.eu/, http://aikido.nohkumado.eu/, http://aikido.zorn.free.fr _______________________________________________ OpenSCAD mailing list [hidden email] http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org