Struggling with Boolean process
goofygrmom3
Posts: 160
I'm trying to work my way thru the Cloud City tutorial. Unfortunately, I just can't get the boolean process to work for me. I've done this before, but not this time. I have the tut printed out so I can follow it carefully. Been working on this for about 2 hours. Can anyone please tell me what the secret is??? I even went back and looked a couple of tut links here. Thanks.
Comments
Hi goofy,
I haven't done this tutorial, and you're more than a little vague about the problem you're having :) Not to worry: making Boolean objects just requires four axioms to cover off.
1) OBJECTS MUST HAVE VOLUME. Not too much to worry about - this axiom is just here to cover off something overlooked with terrain and symlat objects specifically. If you're using terrains or symlats in a Boolean relationship, they must be solid (EDIT: thx Rashad).
2) OBJECTS MUST OVERLAP. Whether you're intersecting, subtracting or excluding, the objects must occupy some common space.
3) AT LEAST ONE OBJECT MUST BE POSITIVE. Neutral objects will not interact with a Boolean operation. A negative (or intersect) object cannot create a Boolean object with another negative (or intersect). Also – and this is the major overlook when creating complex Boolean objects – When you've grouped two or more objects into a Boolean object, that Boolean object, by default, becomes neutral. If this new Boolean object is to become part of a super-Boolean object, you must set it to positive, negative or intersect.
4) OBJECTS MUST BE GROUPED. Sounds obvious, but just placing objects near each other, no matter what Boolean operation they're set to, does nothing. They must be grouped.
5) DO NOT COMBINE BOOLEAN OBJECTS. This is a little unimportant, but it's a trap: From Bryce 6.1 onwards, Boolean objects may be Combined, with the [C] button on the floating palette. This creates a solid mesh of the resulting operation. At first blush, this is brilliant: in super-Booleans, Combine gets rid of almost all the extraneous wireframe clutter used in the Boolean operation. Unfortunately, there are three problems with the Combine tool:
a) It tends to create triangulated meshes that, even with smoothing applied, may not give you the required result, especially for smooth surfaces.
b) Undo is a little unreliable. If you've created a sophisticated super-Boolean, Combine it, and find out it's not what you want, Undo-ing the group could crash Bryce. You should be fine with simple Booleans.
c) Combined objects can create flaws in the scene file. I've had... bad experiences with scenes that have Combined objects: the combined object was permanently unselectable, or the scene kept crashing when trying to manipulate it.
Please note that none of this is relevant to the operation of metaballs.
Good luck!
@Goofy: It's hard to say what's causing you problems without more details. If you could post an image of what you're trying to do, then we'd have a better idea what might be the problem. Try following Oroboros's four steps and see if you don't get what you're after.
This means making the terrain or symmetrical lattice into a "Solid" in the terrain lab.
I may be misunderstanding what you mean to say with this one. I have not had to overlap meshes as such. I can glue together objects that don't touch, so long as both are positives.
In order to create a Boolean object, two or more objects have to share some common space (intersected/overlapped), and grouped.
It's a bit like having eggs for breakfast. I could crack two eggs open in a saucepan and poach them in milk with some salt and pepper. But just because I've 'grouped' all of these ingredients together in a saucepan doesn't mean I've made an omelette. Likewise, If I create two cylinders that don't touch, overlap, intersect or in any way share space, then group them, no Boolean object is created. It's just a bunch of stuff. Grouped.
Boolean arithmetic (named after the mathematician George Boole, who formalised the AND, OR, NOT, XOR operators used by logic machines the world over) requires a logical test between two states to determine a true or false value. In the above analogy, the cylinders I created could be neutral, positive, negative or intersect or any combination of these attributes, but if they're not overlapping at any point the positive object stays as-is, and the negative/intersect object will disappear: no Boolean object is created, as object A doesn't overlap object B.
EDIT: While no Boolean object is created if objects are grouped but don't overlap, you can say this group is in a Boolean relationship. You can move either object through space in an animation, for instance, and if their trajectories cause them to overlap then a changing Boolean shape will emerge in the overlapped space. However, the 'axioms' I listed above are designed from a troubleshooting perspective: often you might group objects together for a Boolean but it hasn't worked as intended, because your angle of view isn't allowing you to see that the objects aren't actually overlapping.
I suspect a lot of Bryce users use grouping... 'incorrectly', meaning many use grouping to collect a bunch of objects together for convenience, AND for creating Boolean objects. As a result, people start thinking grouping = Boolean object. In complex scenes, non-Boolean grouping starts working against you, because each group creates an enclosing box, each with a corner triangle. The viewport becomes cluttered and difficult to manage, especially if supergroups/nested groups are used.
Grouping's main function is to create Boolean objects. If you want to collect a bunch of objects together WITHOUT creating a Boolean object, use parenting. Not only does this drastically reduce viewport clutter, parenting comes with a few more useful parameters grouping can't do.
Thanks all for the input. I will save your info OROBOROS. It's the best explanation I've read.
Sorry I wasn't more specific yesterday. Frustration does that to me. I have a much clearer head today.
If I wish to make a bowl from a sphere using a Boolean operation, I must have two spheres which overlap each other. One must be positive, the other negative, and both must be grouped together. The depth of the bowl is then adjusted by raising or lowering the one sphere which overlaps the other sphere--whether the negative or positive sphere.
I'm going to go back to that tut now. Here's a link to what I'm talking about.
http://www.daz3d.com/bryce-masters-series-cloud-city
Thanks again for your help. I'll post my results when I'm finished.
Hi goofy,
Again, good luck :) I've made a few amendments to both the axioms (and added a fifth, unimportant one) and the follow-up commentary to Rashad's second post, mainly for clarification. Rather than copy/pasting text from posts, you can bookmark threads for future reference :)
Thanks Oroboros. I guess you mean subscribe to this thread, as I don't see any bookmark.
Terminology changes from browser to browser. Basically, go to the main Bryce forum and right-click on the thread title "Struggling with the Boolean process". The pop-up contextual menu should list 'save bookmark' option somewhere. This will probably create a little submenu, asking you where you want the bookmark saved.
I have a 'Notable Bryce Threads' folder into which I save Bryce links.
I remember trying this tutorial but I stopped using Bryce after a few months. Thanks for the reminder, ;-) It will be awesome to try this tutorial again.
Thumbs up to Daz for having all our "Purchases" available to us all the time. :-)
Ororboros - I have this thread set to notify by e-mails. I tried the right click, but nothing about bookmarking showed up. No problem. I also have the thread in my favs.
Mermaid - I love that feature. It's great having all that stuff available. I did the first section and had no trouble with the boolean part. It's just in the 4th step that I'm having trouble. I'm going to go back and look at the first one again. I'm probably just doing one little thing wrong. I'll get it right sooner or later. Today is a new day...
I downloaded the Cloud city and some others that I don't have anymore on my lastest 3year laptop :lol:
@ Mermaid - I often go back to my content library for things that I've lost.
Here's a sample pic... #1 and 3 - the boolean worked fine, #2 did not use boolean. #4 had a bunch of stacked tori inside the outer cylinder and they are supposed to show through the window (the oblong shape). I used masks to make png shapes in Paint Shop Pro so I could assemble this sample.
Can't seem to add the Bryce file.
I spent 2 hours yesterday and 2 hours the day before trying to get that last one right. Today I just did the base again, following the directions very carefully. It worked. So I thought I'd try the next one which is really simple. Followed the directions very carefully. It didn't work. My doors are sticking out just the like the window in #4. I guess you can't teach an old dog new tricks. This project is going the way of many previous ones. It's just too frustrating.
(Image reposted for reference)
#2 & #3 can be made without grouping. Once you've arranged/aligned all the objects in #2, for instance, ungroup everything and parent the sphere, cones and other cylinders to the bottom, long cylinder. Then you can move the model around by selecting just that bottom cylinder, and the child objects will move with it. (If you select ALL objects in the parented model, they will move in unexpected ways, due to the spatial relationship they have with the cylinder.)
The same goes for #3. Create, arrange, and align the objects as you see fit. If you used grouping for some reason to build the model, ungroup everything and parent the cones and sphere to the bottom cylinder. Then you can move the model around by selecting just that bottom cylinder, and the child objects will move with it.
(You can choose any object in the model to be the parent. I just tend to go for the largest, easiest to select object in the model :) )
So to summarize: #2 & #3 don't have to be Boolean groups, strictly speaking: the objects that make up each model could be Positive, Neutral, Intersect or Negative, then parented. No Boolean operation takes place in parenting: Boolean objects need Boolean properties AND grouping, specifically.
OK, let's look at #1.
From what I can make out, #1 requires one Boolean operation to remove the top part of the top cone. It looks like all the other cones and toruses are just assembled and aligned: no Boolean operation or grouping necessary. So if there is any grouping going on in assembling #1, Ungroup everything - don't do any parenting just yet, just Ungroup everything.
To take away the top of the top cone, the top cone's Boolean property must be set to Positive. Another shape (cylinder, cube, another cone) must be created above it, and overlapping it, and set to Negative. Another important note: Name the Negative shape "Base Negative". Then, Group the top cone and the Negative object. The top of the top cone should be immediately truncated in the Nano Preview window, and you can confirm with a quick render.
The Negative shape might not be big enough to remove the top cone completely. At the bottom of the default Bryce interface are the Primitive Selection tools - a microscopic row of icons depicting various default objects ("primitives") you may place in your scene. Click the primitive shape of your Negative object. Drag to select "BaseNegative". You have now selected just that Negative object, and you can now use the Edit tools to re-size the Negative object to truncate your cone better.
There's one final 'good habit' tip that will help you with #4 later on. Select the top-cone group you've just made and click the [A]ttributes... button on the pop-up menu. Note that your new group has the default Neutral Boolean property, meaning it can take no part in additional Boolean operations, whether you group it with something or not. Set it to 'Positive'. (You might want to rename the group 'Base Top' or similar as well.)
To finish, #1 is now made of several ungrouped items and one Boolean object. Parent each of the other cones and toruses to the Boolean object ('Base Top'). Now you can move your entire Base model around by moving just the 'Base Top' group.
===
K, I'mma get a cider, then I'll tackle #4 :)
I really appreciate your response Oroboros. I didn't have any trouble with 1, 2, and 3. It's 4 that gave me grief. Anyhow, I'm walking away from this project for a bit. It's been too frustrating. At this point I don't know when I'll get back to it. However, I'll keep this thread bookmarked and will check back later. Thanks again for trying to help.
No worries. It's the holidays, I was just passing through.
Is the finished effect of #4 meant to look something like this? I made one with transparent walls for clarity.
@Goofy: I think what you've not done in making the windows for the dome is to select everything, ungroup everything then group everything. I went through making the dome and came up with the image below. When I didn't ungroup/regroup everything mine looked like the dome you show. But ungrouping/regrouping and I got what's in the image.
No one is too Old to learn. ;-) The models on the previous page are looking great. I know all about frustration, I stopped using Bryce for a few years and regretted it very much. Leave this project for now and come back to it another day. On Horo's site there are many pdf file tutorials which you can download and there are many written tutorials on http://www.bryce-tutorials.info/bryce-tutorials.html
I haven't started on this tutorial yet and will post my results here when I do get around to it. I'm still have lots of fun with kaleidoscopes and abstracts. :-)
Thanks Oro I like the idea about parenting. I must remember that when I try the tutorial.
Hey, looks like Guss has the tutorial! Cool, I'll go back to being drunk and let him walk you through #4 :)
@Mermaid: If you've been using grouping for everything when you didn't need to, you'll be amazed at how much clutter you'll remove from a model. Selecting objects within a model is a lot easier as well, as there's no surrounding group-box to get in your way.
I'm glad you mention parenting in this thread Oro because I thought it was only when animating. :lol: Every day we learn something new
Thanks once again.
Thanks very much Oro and Guss. That's exactly what I'm trying to do. Maybe I missed something in the ungroup/regroup process.
I know I'm not too old to learn new stuff Mermaid. I'm only 65. But when I can't do something that I've done before I get very frustrated and feel old and stupid. I'll give it a try again and see what happens. If I have any luck, I'll post here. Thanks for the support.
FINALLY!!!!! All the grouping/ungrouping/regrouping has my brain going in 400 directions. But I finally got it to work. Now I can move on to the next step instead of throwing the laptop out the window.
THANK YOU ALL FOR YOUR HELP AND SUPPORT.
My windows are a bit different because I lost the one I already made. But this works and I'll keep it this way.
Oval windows?
..Simple, direct, I like it :D Glad you cracked it, goofy!
At some point I may go back and make the proper window, but for now these are fine.
I have a question... There's a weird box around the overall dome. When I try to add to my object library it comes up blank. All the other pieces of the city worked fine. I can't get rid of the box. If I have to, I guess I can make a new dome with the all the right parts, but I've spent so much time on this one that I'd like to not do that.
Check on it from top camera view and see what is at the other end of that bounding box.
This is zoomed way out. I have no clue what this is. It doesn't show up till I group it.