Booleans are somewhat limiting. If you plan to render boolean models outside of Bryce then you will need to know that from the moment you start building the model because it will greatly affect the workflow. From reading the description you may not find it feasible to send this model to DS because prepping the model will take some effort especially if the model is complex in any way. The issue is with “nested” boolean operations…or better stated… booleans that are multiple generations deep. A few things to keep in mind:
1. Any boolean model that will someday be exported will require “collapsing” via the letter “C.” If you cannot get the letter C to appear, there is no chance you will be able to export this grouped object.
2. To get the option to Collapse, each polygonal object in the group needs to be assigned a polarity either positive, negative, or intersect before they are grouped. So for example, you can boolean a positive sphere to a negative cube. The letter “C: will appear and you will click on it to collapse the primitive based boolean into an actual 3d mesh that is exportable. It is important to note if you don’t already know this that primitives are not true geometry, but merely angular representations of geometry. This will become an important consideration a little later on.
3. Now lets imagine another example but this time we will use three items, a positive sphere, a negative cube, and a neutral cone. When grouped together the letter “C” will not become available because the cone is assigned as neutral. Change the cone to either positive or negative and the C will appear and you can then export the model.
4. If for example, you have three items you want to export and you dont want them to cut into one another but indeed to remain distinct, then you will assign all three as “positive” and when you group them, then letter C will appear. You will then click on the C and export the model as a single group. When you import the resulting model to another application you will see that the three pieces are still individuals and have not been glued together permanently.
5. Primitives are not real geometry as mentioned above. This means that before you make a boolean collapse you will need to specify the polygon density or resolution of the primitives involved in the construction of the given model. The first image example below demonstrates how and where to find the control that allows you to determine the quality of the primitives being collapsed. The higher the setting, the more polygons that will be used resulting in a smoother mesh. But it also takes more time. On angular objects this doesn’t really matter as much, but on spherical objects it makes all the difference in the world.
6. Metaballs are a special consideration. I dont want to go off into it too much but suffice it to say metaballs based objects need to be enlarged physically in Bryce if you want the resulting mesh to have any real quality. If the model is only 3 Bryce units tall and 3 units wide, to get a good mesh you will need to enlarge the object to several hundred to several thousand Bryce units to get a good quality resulting mesh. Indeed, metaballs work very differently than all other forms of geometry in Bryce insofar as exporting and boolean operations are concerned. Remember also that Trees are spawned with metaballs so you should make them large in order to export them with a good degree of detail in the trunk and branches.
7. It is always best once you collapse a mesh to export it into some format 3ds or obj or whatever you like, and then to re-import the model into Bryce and continue from there. The reason is due to the wireframe view boundary boxes, they can get really confusing when dealing with complex boolean operations since the boundary boxes of each component remain intact even after collapse. Reduce that clutter by exporting then re-importing.
8. Lastly, let’s talk about the problem with nested booleans. As mentioned above, if you plan to export a model someday you need to build it in a manner that will make it exportable. The key to this is to avoid nested booleans. Nested booleans are booleans inside of booleans inside of more booleans.. you get the drift. What you should be doing is building each element 1 piece at a time, as you complete an element collapse the primitives then export then re-import and continue. The idea is to never build a complex model comprised of billions of primitives, but instead to convert those million primitives into a few solid 3d meshes and continue from there.
9. As far as getting this all into DS, here is what you would need to do. First, you need to deconstruct your Bryce model to insure that you have avoided all nested boolean operations. This can be nearly impossible for truly complex models, but not so bad for simpler ones. You want to go back to the first boolean group of the project and collapse it. In fact you will need to collapse each boolean stage of the construction. In the end you should be left with a model made entirely of meshes. You can even boolean those resulting meshes together into what could eventually become a single master object. If you need to UV map any parts of the model the time to do that is now. Again, you must have a plan in mind from the beginning.
Hopefully this gives you a good deal to chew on and please report back with any questions or observations Best of luck.
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