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+ Boolean Operations¶
+Boolean operations operate on two solids. The following shapes are +used in the following examples:
+s1 = ccad.sphere(1.0)
+s2 = ccad.box(1.0, 2.0, 3.0)
+s3 is the derived shape.
+
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+Fuse¶
+fuse fuses two solids together. Either one of the two lines below +fuses s1 and s2:
+s3 = s1 + s2
+or:
+s3 = ccad.fuse(s1, s2)
+
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+
+Cut¶
+cut cuts one solid from the other. Either one of the two lines below +cuts s2 from s1:
+s3 = s1 - s2
+or:
+s3 = ccad.cut(s1, s2)
+
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+Common¶
+common finds the common portions of each solid. Either one of the two +lines below finds the common portions of s1 and s2:
+s3 = s1 & s2
+or:
+s3 = ccad.common(s1, s2)
+
+
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+Glue¶
+Boolean operations can have trouble when two solids have coincident +faces. Sometimes the glue function can help. glue merges two solids +at a coincident face. Unfortunately, you need to know the face +indices that must merge. Read more about finding face indices in the +Display or Logging sections:
+s1 = ccad.box(1.0, 2.0, 3.0)
+s2 = ccad.box(1.0, 1.0, 1.0)
+s2.translate((1.0, 0.5, 1.0))
+s3 = ccad.glue(s1, s2, [(1, 0)])
+
+A more robust glue called simple_glue exists in the API, which +isn’t part of OCC. For this form, however, the faces to be glued must +exactly overlap.
+
+
+Notes¶
+Functions to use OCC’s old fuse, cut, and common algorithms, and +functions to perform a fillet or chamfer on the newly created edges +after a boolean operation are also available. I use them rarely. See +the API.
+Sometimes OCC has trouble with booleans. I found the following helpful:
++++
+- Eliminate unneeded edges. OCC’s boolean operations often return +two faces in the same domain with an edge between them that can be +merged. Eliminating these edges by merging the faces help +subsequent boolean operations. The simplify method can do this +for some shapes.
+- Move problem edges out of the way. Cylinder and sphere edges are +necessary in OCC, but their position can often be rotated away +from a problem boolean location.
+- Slice the object (with a box or something) into sections. Then +fuse those sections back together. Then apply the boolean +operation. This was particularly helpful for creating pockets in +a solid.
+