You can try this at home

• Drawing boolean objects - combine parametric and implicit functions

• The boolean object has surfaces from all its constituent objects

• Draw using polygonal meshes, but test before drawing using implicit func.

  • for a hole drilled in a block - the surface of the hole is given by the cylinder used to drill it, the rest of the object’s surface is defined by the block
  • draw points on the block if they are outside the cylinder
  • draw points on the cylinder if they are inside the block

• Implementing union:

  • draw both objects, use hidden-surface algorithms to take care of visibility

• Implementing intersection:

  • draw points only if they are inside both objects

• Implementing subtraction

  • points on the positive object’s surface are visible outside the negative object
  • points on the negative object’s surface are visible inside the positive object

• Draw using parametric functions, trim using implicit functions

  • And that’s where the tricky part comes in

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