BOOLEAN MODIFIER
Boolean Modifier can be used to do the following three operations on an object- ie, union, intersect or difference.
When we apply an union operation then the end result is the combined shape of the two objects. Intersection is the the shape of the two objects where they commonly intersect. In case of difference, it the shape of the second object is removed from the first object. As an example if you consider a cube and a cylinder. when you do an union operation it will be the combined shape of the two objects. If you do intersection then it will be length of the cylinder which is intersecting with the cube will be the result. In case of difference the end result will be a cube in which the volume up to which the cylinder intersects with the cube is removed as if a hole is drilled in the cube body.
To apply the Boolean Modifier, the steps are as follows: In the 3D window, add a Cube scale it 3 time along the X and Y axis. Add a cylinder and scale it 5 times along Z axis only.
To do the union operation, locate the Cube a convenient location, the position the cylinder on the Cube such that about 3 units length of the cylinder is inserted into the Cube.
Now go to the Properties window and click on the spanner icon to open the Add Modifier drop down menu. Click on "Add Modifier" . Under Generate heading,click on Boolean, under operation select Union. Select the Cube in the 3D panel, under Object click inside the window where you see an ink dropper icon. Select the cylinder. Then click on the Apply
button. Click on the cylinder to select it and drag it away. You will the Cube and cylinder joined as a single object.
Follow the same procedure for intersect or difference. Corresponding to this operation the setting under "Operation" should be selected as Intersect or Difference.Then click on Apply. After the operation move the cylinder away to see the end result.
NOTE: When you are positioning the two object in the 3D window, under "View Port shading" select wire frame. This will give wire frame view of both the objects.This view option is preferable over the solid view option.
