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Found a couple more doc errors in isosurface.scad

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Alex Matulich 2025-01-24 17:48:50 -08:00
parent cf88fe9b54
commit 83fa2ca37b
1 changed files with 7 additions and 6 deletions
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isosurface.scad
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@ -29,7 +29,7 @@ Unlike the original paper (Marching Cubes: A High Resolution 3D Surface Construc
Rotations are prioritized over inversions so that 3 of the 6 cases containing ambiguous faces are never added. 3 extra cases are added as a post-process, overriding inversions through custom-built rotations to eliminate the remaining ambiguities.
The cube index determines the sequence of edges to split. The index ranges from 0 to 255, representing all possible combinations of the 8 corners of the cube being greater or less than the isosurface threshold. For example, 10000110 (8-bit binary for decimal index 134) has corners 7, 2, and 3 greater than the threshold. After determining the cube's index value, the triangulation order is looked up in a table.
The cube index determines the sequence of edges to split. The index ranges from 0 to 255, representing all possible combinations of the 8 corners of the cube being greater or less than the isosurface threshold. For example, 10000110 (8-bit binary for decimal index 134) has corners 2, 3, and 7 greater than the threshold. After determining the cube's index value, the triangulation order is looked up in a table.
Axes are
z
@ -58,9 +58,9 @@ Vertex and face layout for triangulating one voxel face that corrsesponds to a s
4(back)
3 +----------+ 7
/: 5(top) /#
/ : / #
1 +==========+5 # <-- 3 (side)
/: 5(top) /|
/ : / |
1 +==========+5 | <-- 3 (side)
0(side) --> # 2+ - - - # -+ 6
# / # /
#/ 2(bot) #/
@ -663,7 +663,8 @@ _MCTriangleTable_reverse = [
// smaller for final rendering. If the isosurface fits completely within the bounding
// box, you can call {{pointlist_bounds()}} on `vnf[0]` returned from the
// `isosurface()` function to get an idea of a more optimal smaller bounding box to use,
// possibly allowing increasing resolution by decresing the voxel size.
// possibly allowing increasing resolution by decresing the voxel size. You can also set
// the parameter `show_stats=true` to get the bounds of the voxels containing the surface.
// .
// The point list in the VNF structure contains many duplicated points. This is not a
// problem for rendering the shape, but if you want to eliminate these, you can pass
@ -704,7 +705,7 @@ _MCTriangleTable_reverse = [
// bbox = [[-100,-100,-100], [100,100,100]];
// isosurface(voxel_size=5, bounding_box=bbox, isovalue=0,
// field_function=gyroid, additional=200);
// Example(3D,ThrownTogether,NoAxes): To make the gyroid a double-sided surface, we need to specify a small range around zero for `isovalue`. Now we have a double-sided surface although with `clip_close=false` the edges are not closed where the surface is clipped by the bounding box.
// Example(3D,ThrownTogether,NoAxes): To make the gyroid a double-sided surface, we need to specify a small range around zero for `isovalue`. Now we have a double-sided surface although with `close_clip=false` the edges are not closed where the surface is clipped by the bounding box.
// gyroid = function (xyz, wavelength) let(
// p = 360/wavelength,
// px = p*xyz[0],