Yes I am running into more trouble. Please do not link me to any tutorials because I have several bookmarked and another very detailed guide DLed to my harddrive.
I am having trouble with boolean operations. The guide says to use Boolean Difference to make a hollow object. I made one large cube. I then made a slightly smaller one and put it behind the orginal, bigger cube. I then selected both in object mode and hit the w key. I then proceeded to click Difference in the menu that popped up. However, I didnāt see any changes. After that I tried to make a window using the same process but it didnāt work. Am I doing something wrong?
BTW, booleans do not work perfect in blender as of yet. You can do a serch here for a script that works better.
EDIT: Sorry, this is one more thing which may be the āproblemā. When you do a boolean operation, it make a copy of your objects. So try moving the cubes after you do the boolean.
And my ascii diagram doesnāt look the same as it did in the edit box. Hmmm.
I find that boolean operations usually give me far more faces than I wanted to begin with, and they muck-up the entire model, so I avoid them completely. Itās easier (imho) to do it by hand. And you get a cleaner result.
If youāre familiar with scan-fill (flood-fill) operations, thatās the basic difference between inside and outside. Outside is what you see (from the camera) and inside is what you canāt. (The trick, of course, is to not move the camera insideā¦)
Thereās nothing wrong with asking questions. Better titles than āI need helpā are a good idea though (like āboolean ops are confusing meā or somesuch).
BTW, booleans do not work perfect in blender as of yet. You can do a serch here for a script that works better.
EDIT: Sorry, this is one more thing which may be the āproblemā. When you do a boolean operation, it make a copy of your objects. So try moving the cubes after you do the boolean.
And my ascii diagram doesnāt look the same as it did in the edit box. Hmmm.[/quote]
Hmmmā¦ didnāt seem to work. Now I have half a cube stickin out of my houseās wall.
Sorry, Iām a complete n00b and am not famiiar with scan-fill operations.
Scan-fill works like this. Say you have a geometric figure:
+------+
x | |
y | +--+ |
| | | |
+-+ +-+
And you want to know whatās inside and whatās outside.
Suppose we start at x. We start outside. Moving right, we hit a wall. Now weāre inside. Keep moving right. We hit another wall, so now weāre outside. Thereās no more walls to hit so weāre done.
Suppose we start at y. Moving right, we hit a wall. Now weāre inside again. Moving right, we hit another wall. Outside again. etc.
Thatās the way things work in 3D. The difference between āinsideā and āoutsideā is a matter of where you put your xās and yās (i.e. your camera).
Anyway, my whole point was that you usually get a better result by joining the two objects you plan to do your boolean operations with then deleting the vertices you donāt want and manually connecting them where you want them to be connected.
Seriously, though, if you even use the boolean command, a new object is made. Your two other objects are left intact, while a new object is made. I suggest that you at least look at the new object each time. If it isnāt right, then try selecting the objects in a different way and run the boolean operation again.
Thatās the whole point. Itās not solid. Itās a collection of 8 vertices connecting 6 faces. āSolidā and āhollowā mean nothing. Thereās nothing there but the faces and vertices.
So if you were to cut the cube in half, itād be like cutting a cardboard box in half. Thereās nothing there but the sides of the box.
That was also the point behind the scan-line thing. If you want the cube to be āsolidā after youāve cut it in half, you have to add the face thatās missing. Youād get the same result if youād just grabed four of the vertices and moved them closer to the other side.
The only difference between āsolidā and āhollowā, etc., are how it is perceived. If, when you look at the picture of, say, an apple with a bite out of it, we perceive it as āsolidā because thatās how apples are in real life. But in the computer, thereās nothing underneath what you see. The apple and the bite are both just a collection of vertices connected by faces. Itās a magic trick ā a visual sleight of hand.
Boolean operations take two meshes and try to mimic the āsolidā concept, but theyāre really just manipulating which faces to keep and which faces to throw away between the two objects.
Thatās the whole point. Itās not solid. Itās a collection of 8 vertices connecting 6 faces. āSolidā and āhollowā mean nothing. Thereās nothing there but the faces and vertices.
So if you were to cut the cube in half, itād be like cutting a cardboard box in half. Thereās nothing there but the sides of the box.
That was also the point behind the scan-line thing. If you want the cube to be āsolidā after youāve cut it in half, you have to add the face thatās missing. Youād get the same result if youād just grabed four of the vertices and moved them closer to the other side.
The only difference between āsolidā and āhollowā, etc., are how it is perceived. If, when you look at the picture of, say, an apple with a bite out of it, we perceive it as āsolidā because thatās how apples are in real life. But in the computer, thereās nothing underneath what you see. The apple and the bite are both just a collection of vertices connected by faces. Itās a magic trick ā a visual sleight of hand.
Boolean operations take two meshes and try to mimic the āsolidā concept, but theyāre really just manipulating which faces to keep and which faces to throw away between the two objects.
I hope this makes better senseā¦[/quote]
Actually, it makes a lot more sense now. Thanks a lot Duoas!
