Simple Boolean Subtraction
|Anim8or v.08 has no Boolean Subtraction tool, mainly because
it’s a surface modeler, not a solid modeler. However, creative people
Anim8or's powerful modeling tools (extrude, detach, merge, delete,
and so on) to make objects that look like Booleans.
( images by Lloyd Schoenbach)
In this tutorial we shall create the objects shown below, but we won't need drilling and carving tools. We shall simulate Boolean subtraction without moving any vertex from its position; instead we are going to have a hard time with transparency mapping.
A transparency map is an image file (usually gray scale), which tells Anim8or how transparent to make an object. Where the map is darker, the corresponding part of the mapped object is more transparent. Black on the map corresponds to total transparency on the object, while white means opaque.
I intended to do this tutorial accessible for less experienced anim8ors, so let me be excused for the boring step-by-step instructions in the preliminary part.
Now, prepare yourself for Exhibit A, obtained by subtracting from a cube the object seen on the right. You may download the project file(7KB).
1. Create the object to be subtracted, as follows:
- Make a standard sphere, double-click it and change its diameter to 50.
- Convert it to mesh (Build->Convert to Mesh).
- In point edit mode, drag-select a row of vertices.
Change to top view, select the Non-uniform scaling tool and drag
on a slope of
approx.45 degrees to shrink, or grow the selected circle as you whish.
- Back to front view, select other rows and repeat the scaling as above.
- In front view move vertically entire rows, as you desire.
Finally, back to normal Edit mode, select your object and do
It’s not important to reproduce identically the object done by me, it’s only a reference. This is how the vertices were displaced (right image):
2. Create a cube
Make a cube, double-click it, make the size 50 on each axe. Convert it to mesh. With the cube selected, click Edit->Locate->Center About Origin
3. Position the objects
In front view select the object created at step 1 and do Edit->Rotate->Rotate X90. Now position the object over the front face of the cube, without intersecting the margins of the face. Change to side view and insert the object in the cube, almost entirely, so that only a thin convex part to remain outside, like in the wire frame image on the left.
Now, that we have created and positioned the objects, let’s start with the Boolean Subtraction!