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    • S Offline
      soldatino
      last edited by

      I am sorry but I use this topic because it seems to be about my question.
      I make a solid using the help example for smooth surfaces (6 sides), then I push for the elevation, then I select all the object, then I apply Soften edges angle 79,0 degrees, and the edge appear soft.
      But if I get the normals at each point I read always (0, 0, 0), that is not a valid vector.
      Sorry, where I am wrong?

       
      for np in 1..numpol do
        vertices=mesh.polygon_at np
        numvrtx=vertices.length - 1
        for eachvrtx in 0..numvrtx do
          x = mesh.point_at((vertices[eachvrtx]).abs).x*RatioPov
          y = mesh.point_at((vertices[eachvrtx]).abs).y*RatioPov
          z = mesh.point_at((vertices[eachvrtx]).abs).z*RatioPov
      
      
          nx = mesh.normal_at (eachvrtx+1) #index is base 1
          UI.messagebox(nx.to_s)
      

      r3nDer tools

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      • thomthomT Offline
        thomthom
        last edited by

        @soldatino said:

        I make a solid using the help example for smooth surfaces (6 sides

        Which example?

        @soldatino said:

        But if I get the normals at each point

        I think that .normal_at( index ) refer to the normal of a polygon - not point...

        Thomas Thomassen — SketchUp Monkey & Coding addict
        List of my plugins and link to the CookieWare fund

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        • S Offline
          soldatino
          last edited by

          Error 404 (Not Found)!!1

          favicon

          (code.google.com)

          but this is about points "particular index in the mesh."
          Or it is for each face? In this case I have to calculate each angle between vertexes of adjacent faces?
          Anyway the vector that I get is 0,0,0, but the faces have smooting in SU.
          http://sketchup.google.com/support/bin/answer.py?hl=it&answer=114941
          the procedure is explained in the yellow window..

          r3nDer tools

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          • thomthomT Offline
            thomthom
            last edited by

            I think "particular index in the mesh." refer to the index of polygons.

            @soldatino said:

            Anyway the vector that I get is 0,0,0, but the faces have smooting in SU.

            Normals in SketchUp does not relate the smoothing. Normals are always perpendicular to the face/polygon.

            To find out of the mesh has smooth edges use PolygonMesh.polygon_at http://code.google.com/intl/it/apis/sketchup/docs/ourdoc/polygonmesh.html#polygon_at or PolygonMesh.polygons http://code.google.com/intl/it/apis/sketchup/docs/ourdoc/polygonmesh.html#polygons

            Thomas Thomassen — SketchUp Monkey & Coding addict
            List of my plugins and link to the CookieWare fund

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            • S Offline
              soldatino
              last edited by

              yes, thanks, pointing at the face I get the float values of the vector.
              Now if it is a offset valid for all the points of each face, I have to find the common points of adjacent faces, and interpolate their offsets to get the vector for the points. A lot of work... do yo think it is right?

              r3nDer tools

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              • thomthomT Offline
                thomthom
                last edited by

                Think so - SU doesn't provide vertex normals.
                When I wrote Vertex Tools I have to work them out manually from the connected faces.

                Thomas Thomassen — SketchUp Monkey & Coding addict
                List of my plugins and link to the CookieWare fund

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                • TIGT Offline
                  TIG Moderator
                  last edited by

                  Look at a vertex.
                  Get its faces.
                  Get the normals of the faces [lets say there are 3 of them].
                  Combine the faces' normals [vectors] using v = v1 + v2 + v3
                  Now 'v' should be the combined-vector at that vertex [the vertex-normal?]...
                  Test it using entities.add_line(vertex.position,v.to_a)
                  which should draw a line at the vertex along the direction of the combined-vector 'v'...

                  TIG

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                  • S Offline
                    soldatino
                    last edited by

                    thomthom, TIG, thanks. I will attempt to write this in Ruby, even if I dont know much of this language, to do it with a post editor would be very easy, storing the array of all the normals of every face as comments within the ouput of the points ...

                    note: Vertex.used_by? in a loop of all connected faces ? waiting for the eternity...

                    r3nDer tools

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                    • thomthomT Offline
                      thomthom
                      last edited by

                      @soldatino said:

                      note: Vertex.used_by? in a loop of all connected faces ? waiting for the eternity...

                      ❓

                      Thomas Thomassen — SketchUp Monkey & Coding addict
                      List of my plugins and link to the CookieWare fund

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                      • S Offline
                        soldatino
                        last edited by

                        @thomthom said:

                        @soldatino said:

                        note: Vertex.used_by? in a loop of all connected faces ? waiting for the eternity...

                        ❓

                        I am worried because I think that with large model the time required will be huge.
                        Addictionally I would not repeat the calculation for the same point when the loop scans the already involved faces, but if I do not want to repeat I have to save an array for all the entities, containing normals already calculated, and to scan it also, which could be worse...

                        r3nDer tools

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                        • thomthomT Offline
                          thomthom
                          last edited by

                          What are you doing? An exporter?

                          Thomas Thomassen — SketchUp Monkey & Coding addict
                          List of my plugins and link to the CookieWare fund

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                          • thomthomT Offline
                            thomthom
                            last edited by

                            <span class="syntaxdefault"><br />&nbsp;&nbsp;</span><span class="syntaxkeyword">for&nbsp;</span><span class="syntaxdefault">eachvrtx&nbsp;in&nbsp;0.</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">numvrtx&nbsp;</span><span class="syntaxkeyword">do<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="syntaxdefault">x&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">mesh</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">point_at</span><span class="syntaxkeyword">((</span><span class="syntaxdefault">vertices</span><span class="syntaxkeyword">[</span><span class="syntaxdefault">eachvrtx</span><span class="syntaxkeyword">]).</span><span class="syntaxdefault">abs</span><span class="syntaxkeyword">).</span><span class="syntaxdefault">x</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br />&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">mesh</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">point_at</span><span class="syntaxkeyword">((</span><span class="syntaxdefault">vertices</span><span class="syntaxkeyword">[</span><span class="syntaxdefault">eachvrtx</span><span class="syntaxkeyword">]).</span><span class="syntaxdefault">abs</span><span class="syntaxkeyword">).</span><span class="syntaxdefault">y</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br />&nbsp;&nbsp;&nbsp;&nbsp;z&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">mesh</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">point_at</span><span class="syntaxkeyword">((</span><span class="syntaxdefault">vertices</span><span class="syntaxkeyword">[</span><span class="syntaxdefault">eachvrtx</span><span class="syntaxkeyword">]).</span><span class="syntaxdefault">abs</span><span class="syntaxkeyword">).</span><span class="syntaxdefault">z</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br /></span>
                            

                            Change into this

                            <span class="syntaxdefault"><br />&nbsp;&nbsp;</span><span class="syntaxkeyword">for&nbsp;</span><span class="syntaxdefault">eachvrtx&nbsp;in&nbsp;0.</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">numvrtx&nbsp;</span><span class="syntaxkeyword">do<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="syntaxdefault">pt&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">mesh</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">point_at</span><span class="syntaxkeyword">((</span><span class="syntaxdefault">vertices</span><span class="syntaxkeyword">[</span><span class="syntaxdefault">eachvrtx</span><span class="syntaxkeyword">]).</span><span class="syntaxdefault">abs</span><span class="syntaxkeyword">)<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span class="syntaxdefault">x&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">pt</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">x</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br />&nbsp;&nbsp;&nbsp;&nbsp;y&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">pt</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">y</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br />&nbsp;&nbsp;&nbsp;&nbsp;z&nbsp;</span><span class="syntaxkeyword">=&nbsp;</span><span class="syntaxdefault">pt</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">z</span><span class="syntaxkeyword">*</span><span class="syntaxdefault">RatioPov<br /></span>
                            

                            Should be a little bit faster.

                            Thomas Thomassen — SketchUp Monkey & Coding addict
                            List of my plugins and link to the CookieWare fund

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                            • S Offline
                              soldatino
                              last edited by

                              This is a part of my exporter to POV-Ray. Yes, now I apply your suggestion !

                              r3nDer tools

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                              • S Offline
                                soldatino
                                last edited by

                                SenzaTitoloSTa.jpg

                                17/11/2010 10:03:00
                                //Ending at 17/11/2010 10:03:18

                                17/11/2010 10:09:00
                                //Ending at 17/11/2010 10:09:18

                                28935 faces
                                Later I will check on largest files...

                                r3nDer tools

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                                • T Offline
                                  tomasz
                                  last edited by

                                  @thomthom said:

                                  Think so - SU doesn't provide vertex normals.

                                  You are wrong Thomas!
                                  Check this :
                                  polygonmesh.normal_at(vertex_index)

                                  Soldatino, your exporter will work faster now 😄
                                  I think that is what you have been looking for, unless you want to do vertex welding.

                                  Author of [Thea Render for SketchUp](http://www.thearender.com/sketchup)

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                                  • thomthomT Offline
                                    thomthom
                                    last edited by

                                    @unknownuser said:

                                    @thomthom said:

                                    Think so - SU doesn't provide vertex normals.

                                    You are wrong Thomas!
                                    Check this :
                                    polygonmesh.normal_at(vertex_index)

                                    ?

                                    From the docs I see nothing that indicate vertex index. http://code.google.com/apis/sketchup/docs/ourdoc/polygonmesh.html#normal_at
                                    Saying that - it doesn't even say if it's polygon index.

                                    Tomaz: you got a working example?

                                    Thomas Thomassen — SketchUp Monkey & Coding addict
                                    List of my plugins and link to the CookieWare fund

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                                    • T Offline
                                      tomasz
                                      last edited by

                                      @thomthom said:

                                      Toma**s**z: you got a working example?

                                      Yep. SU2TH 😄

                                      You have to extract a triangle indexes using
                                      tri_indexes=polygonmesh.polygon_at(mesh_index)
                                      and then
                                      normal0=tri.normal_at(tri_indexes[0]) normal1=tri.normal_at(tri_indexes[1]) normal2=tri.normal_at(tri_indexes[2])

                                      The docs are .... terribly bad, you know that you can't rely on them 😄

                                      Now you know how to use it and speed-up your plugins.

                                      EDITED. I was terribly wrong 😄 It is correct now.

                                      Author of [Thea Render for SketchUp](http://www.thearender.com/sketchup)

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                                      • thomthomT Offline
                                        thomthom
                                        last edited by

                                        I can't get it working...
                                        PolygonMeshNormals.png

                                        Thomas Thomassen — SketchUp Monkey & Coding addict
                                        List of my plugins and link to the CookieWare fund

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                                        • T Offline
                                          tomasz
                                          last edited by

                                          Do not count_points, count_polygons instead.
                                          1 .. mesh.count_polygons
                                          then

                                          {
                                          tri_indexes=mesh.polygon_at(i)
                                          (0..2).each{|q| p mesh.normal_at(tri_indexes[q])}
                                          }
                                          

                                          EDIT.
                                          use mesh 7 to ensure you get also normals. Doc doesn't say what is a default flag.

                                          Author of [Thea Render for SketchUp](http://www.thearender.com/sketchup)

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                                          • thomthomT Offline
                                            thomthom
                                            last edited by

                                            But when you do 1 .. mesh.count_polygons you iterate over the polygons. And mesh.polygon_at(i) returns an array of point (vertex) indexes - which are the same indexes you get when you iterate mesh.count_points...

                                            ??

                                            PMIndex.png

                                            Thomas Thomassen — SketchUp Monkey & Coding addict
                                            List of my plugins and link to the CookieWare fund

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