I tried to get this one before, if you use a sphere you end up with a ring, and if you use a cone and rotate the x angle by 90 and then run the code you end up with a part cone cut out and over cut out with the rest of the box.
make object cone 3,20
rotate object 3,90,0,0
if these two do get fixed then it will make for cutting out parts in object 99.9% correct.
edit
if I scale the cylinder before I do the cut out I get the result I hoped for :-
Rem ***** Main Source File *****
set display mode 800, 600, 32, 1
sync on
sync rate 60
autocam off
position camera 0,0,-100
make object box 2,20,20,20
make object cylinder 3,10
scale object 3,100,200,100
make mesh from object 1,3
if file exist("testmesh.x")=1 then delete file "testmesh.x"
save mesh "testmesh.x",1
delete object 3
load object "testmesh.x",3
PERFORM CSG DIFFERENCE 2,3
delete object 3
while escapekey()=0
rotate object 2,x#,0,0
inc x#
sync
endwhile
however if I just use the cylinder without scaling I should ens up with a hole inside the box and should not be able to see it unless I cut the box in half.
Rem ***** Main Source File *****
set display mode 800, 600, 32, 1
sync on
sync rate 60
autocam off
position camera 0,0,-100
make object box 2,20,20,20
make object cylinder 3,10
make mesh from object 1,3
if file exist("testmesh.x")=1 then delete file "testmesh.x"
save mesh "testmesh.x",1
delete object 3
load object "testmesh.x",3
PERFORM CSG DIFFERENCE 2,3
delete object 3
while escapekey()=0
rotate object 2,x#,0,0
inc x#
sync
endwhile
When you use the above code it works but if you look you can see blue background inside the box, which I should not be able to see, as the cutout is smaller than the box there should be no circular hole on the faces of the box.
this code shows a cut out, however I should not have a cut out a above or below the cylinder on the box face, you should see a small hole which is curved insided.
Rem ***** Main Source File *****
set display mode 800, 600, 32, 1
sync on
sync rate 60
autocam off
position camera 0,0,-100
make object box 2,70,16,70
make object cylinder 3,20
rotate object 3,90,0,0
`scale object 3,200,100,250
make mesh from object 1,3
if file exist("testmesh.x")=1 then delete file "testmesh.x"
save mesh "testmesh.x",1
delete object 3
load object "testmesh.x",3
PERFORM CSG DIFFERENCE 2,3
delete object 3
while escapekey()=0
rotate object 2,x#,0,0
inc x#
sync
endwhile
edit2
after some experimenting the point of a cone works OK but not the base, working out how far the non visual part of the cone base goes.
edit 3
made sphere in AC3D saved as 3ds and that worked ok, but a cylinder and cone with closed ends when CSG ended up with the box part having parts of its face missing when part insterted to make cutout that do not go all the way through the object.
Dark Physics makes any hot drink go cold.