The result: width = 59,053% of the height. The stroke must be removed before it, because it's half out of the actual ellipse. After rotating the ellipse 30 degrees one can read the height and width as bounding box dimensions. With it I made the full ellipses:Ĭomparing the ellipse to the grid shows that rotating the ellipse 30 degrees makes it vertical. Measuring was possible with Inkscape's path effect "Ellipse by 5 points". Calculating the exact formulas for the arcs unfortunately need 3D projection geometry math skills beyond my level, so I measured the extracted arcs. Those ellipses must be non-proportionally squeezed circles and the arcs must originally be 90 degrees sectors of the circles before squeezing. The bending arcs must be parts of ellipses. 3D software would do it much better with virtually zero own effort: I tried only to draw some blurred white and black strokes over the shape. The orange lines are drawn to show, where the joints between straight and bended parts should be:Ĭoloring this for a good 3D-like shading isn't trivial. The bending curves snapped to the grid by scaling. In the next image 2 bends are constructed. In addition a couple of cross-section ellipses was drawn one horizontal snapping to the grid and a copy of it, but rotated 60 degrees: The wireframe was printed as PDF, imported to Inkscape and only the bending curves were saved. The images of the bending curves are the essential part that I reuse. The cross-sections are actually useless,because they have nodes in not so good places. The radiuses are a little bigger than in the first image. I made a reduced wireframe which has the extrusion path and some pipe cross-sections.
Some tests revealed that scaling the curved part of the extrusion path was quite plausible outline. I cannot calculate how they should be drawn with the grid, but I could export the isometric vector image of the wireframe.
Draw a horizontal version and make 60 and 120 degrees rotated copies.īending curves are complex. The cross-sections of the pipe are ellipses which can be drawn easily with the isometric grid. Before extrusion I made circular roundings to the corners of the extrusion path: I extruded a circle along the edges of a cube. To figure out the wanted looks I made a simple extrusion in a freeware 3D CAD program. We have got even another answer which uses Illustrator's 3D. Of course perfect result is possible in a 3D program. the visible curved outlines are the actual problem - how to produce them consistently and easily enough? Coloring the pipes to have 3D-like shading tolerates much variation because the light isn't exactly specified beforehand.
I guess the projections of the bendings ie.
0 kommentar(er)
