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Modelling With Boolean Operations:

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E-mail Billy.

 

 

Check in more than one view to be sure that they actually intersect.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Radio Buttons:

These offer a choice between a few different options. Only one Radio Button can ever be selected at one time. Selecting one will automatically deselect the other. (Unlike Check-Boxes,

 which allow multiple selections).
I could spend ten minutes explaining the principles of Boolean Operations, but in my experience the best way to understand a process is to do it, so lets just do some....

  • Create two primitives that intersect one another. I've chosen two spheres, so if you want to keep it simple, just copy me:

  • Now go to the Create Panel and click on the word Standard Primitives. This will open a drop-down menu like so:

  • Choose Compound Objects

  • Make sure that one of your Primitives is selected.

  • Choose Boolean from the Create Menu.

  • The following menu should open.  

 

  • Leave the radio buttons under Operation set to Subtraction (A-B)

  • Click Pick Operand B. It should turn green.

  • Click on your second primitive object in any of the viewports.

 
The result should be that your second primitive is subtracted from the first. 

The object that you originally select before performing a Boolean is always Operand A. 

You will notice that Operand B disappears when you select it. This is because you have the Move radio button selected:

The Move option uses the actual object itself as Operand B. However, you can also choose to use a Copy, Reference or Instance of the object. This way you still have the original. If you use the Instance or Reference options, any changes you make later to the original will effect the geometry of Operand A.

Now try the other Boolean Operations. You don't need to start again, you simply need to select a different radio button in the Operation section of the menu. The rest of the operations work as follows:
Union:  Joins Operands A and B
Intersection: Subtracts everything except the area where the two Operands Intersect.
Subtraction (B-A) Subtracts Operand B from Operand A
Cut Uses operand B to cut into the mesh of Operand A (Don't worry about this one, we wont be using it!)
Ok, play around with this for a while. Add some new objects to the scene, move them around so that they intersect with your new "Compound Object", and perform some Boolean Operations.

If you already have some more objects in the scene, pressing the Boolean button again will complete the previous Boolean Operation and allow you to start a new one.

If you would like to go into more depth about Boolean Operations, read pages 243 to 259 in the "SAMS Teach Yourself..." recommended text.
Start to look around you at objects in your house and work out what can be broken down into a combination of primitive objects. You'd be surprised just how many things there are! Find something simple and have a go at modelling it using Boolean Operations.

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