Mandelbulb 1.91 BTracer error

[hirnlaich]

Maybe I´m doing something wrong, with the new BTracer, but no luck to export any .obj file.

[thargor6]

Which OS you are using? It seems to accept floating point values only in language-specific notation, e. g. "0,42" instead of "0.42".
You could try this to circumvent the problem until a solution is available.

Cheers!

[JFR]

I hope you don't mind me asking this in your thread, but I was curious about the highest mesh resolution people have been able to export out of MB3D.
I have been able to get up to a resolution of 750. Anything higher it seems the progress bar gets stuck at about 95% after which a seemingly idle
process of very little CPU usage kicks in for about 20 minutes. After which a german error message pops up which I believe tells me that my machine
does not have enough horsepower or memory to complete the task. I have ran tests on a multitude of workstations and it seems that the power of
the machine has very little to do with the ability to complete the exports at resolutions of 800 and higher.

I was hoping to find out if anyone else has experienced this, or had more luck exporting higher resolution meshes successfully.

[thargor6]

About 750 is the current maximum. But, it depends of the concrete mesh, so there is no hard limit.
The mesh-merging algorithm tries to be as efficient as possible in terms of memory consumption (which cause a rather slow collection phase at the end with slow CPU usage), but at those size there is the limit of MB3D being a 32bit app.

I thought a lot about this, thought about to circumvent the nasty 32 bit limit, but finally did it not by design. I think, it makes no fun to produce meshes with more than 2 GB in size, imagine a modern computer with, say 64 MB of ram, you do not want a mesh with 30 GB of size. The approach of MB3D is to be more smart in creating meshes which will (hopefully) achieved in future releases. The V1.91 ist just the foundation for much more to come.

What would be a good feature would be do have the preview in a separate process. Now the 32bit limit holds true for the whole app with all features, making it impossible to preview huge meshes

The german error message is a bug, which will be fixed.

[taurus]

I thought a lot about this, thought about to circumvent the nasty 32 bit limit, but finally did it not by design. I think, it makes no fun to produce meshes with more than 2 GB in size, imagine a modern computer with, say 64 MB of ram, you do not want a mesh with 30 GB of size. The approach of MB3D is to be more smart in creating meshes which will (hopefully) achieved in future releases. The V1.91 ist just the foundation for much more to come.

Did not test the new feature so far, but this might be only half of the truth. I used to produce hi-res meshes from fractal zplot. Many modern 3d-Packages have most efficient polygon reduction algorithms, so a 4Million poly model can be reduced up to 95% (200 000) without significant loss of quality. From this point of view, higher poly-numbers might still be useful.

[thargor6]

Did not test the new feature so far, but this might be only half of the truth. I used to produce hi-res meshes from fractal zplot. Many modern 3d-Packages have most efficient polygon reduction algorithms, so a 4Million poly model can be reduced up to 95% (200 000) without significant loss of quality. From this point of view, higher poly-numbers might still be useful.

I think, it is a misunderstanding.
I was not talking about 4Milion poly meshes, MB3D can already create 10Milion poly meshes. I meant, it makes not much sense to go further and create 50Milion poly meshes. Most people will not have the hardware to process them, they will not even spend the money on some of the modern 3d-packages.
Of course, it might be useful. But this would take a huge effort because of being MB3D a dead 32bit horse ;-)

[thargor6]

Maybe I´m doing something wrong, with the new BTracer, but no luck to export any .obj file.
<Quoted Image Removed>

Regarding the original intent of this thread: I created a revision 2 which should fix the problem, please test it if you can: Mandelbulb3Dv191r2.zip

[taurus]

I think, it is a misunderstanding.
I was not talking about 4Milion poly meshes, MB3D can already create 10Milion poly meshes. I meant, it makes not much sense to go further and create 50Milion poly meshes. Most people will not have the hardware to process them, they will not even spend the money on some of the modern 3d-packages.
Of course, it might be useful. But this would take a huge effort because of being MB3D a dead 32bit horse ;-)

Ok, I see. I need to test it myself, first. Sounds promising, to get rid of complicated voxelstacks, that are not really reducible by design...

[thargor6]

Ok, I see. I need to test it myself, first.

Any feedback is welcome as I currently have no time to use it by myself, unfortunately

Cheers!

[taurus]

Wow, Andreas. The B-Tracer is a fantastic improvement for mesh generation. The inital mesh already shows a far superior quality compared to a voxel stack. And for me even more important, it contains a directional mesh, not the typical voxel stairs. This means, that the model is ready for efficient optimisation / poly reduction. I attached a quick render of a mesh I created this morning @ 300x300x300 and 2x2x2 oversampling.
I'm shure this module will lift the way we generate poly models of fractals to a new stage. Thanks Andreas!
Two things need to be done now (in my opinion)

• the B-Tracer creates so far only a mesh surface. In order to 3d print models we need a volume object. It'll be nice, if m3d can do this within the tracer. In best case as additional option, not the only behaviour.
• Finetuning the tracer is nifty. So it would be great, to save the work. In the medium-term only very few people will further on use voxelstacks, so I see no problem in replacing this module by the B-Tracer

A final question. The tooltip, does not clarify for me. What is the "surface iso value" and what can I affect with it?

[thargor6]

The tooltip, does not clarify for me. What is the "surface iso value" and what can I affect with it?

Nice work, and thanks for the feedback!

In simple words, the iso-value specifies where to create the "skin" of the object, when taking into account the density of the object inside a voxel.
By varying this value you can change somewhat like the "thickness" of the mesh-representation of your object (in a rather small range).

You may try this out with some simple object to see the effect, maybe a grid-like object.

Cheers!

[taurus]

I think, I've got an Idea now, what the iso value does. lower values lead to a "tighter" skin, more details, but also the tendency to more "stairy" meshes. So far the default 0.25 showed the best result in my attempts. So I'll leave it untouched in the next steps. BTW here is my first handmade solid. It is possible...

[thargor6]

Again, nice work!
When using higer levels of oversampling, changing the value of iso-value can be interesting. But, this needs some tries-and-errors, because there are so many possible different shapes. I also found out, that 0.25 gives good results in most cases, so I chose this as default. (I. e., there is no "magic" behind the value, just my initial guess for a good default value)

Cheers!

[KRAFTWERK]

...

• the B-Tracer creates so far only a mesh surface. In order to 3d print models we need a volume object. It'll be nice, if m3d can do this within the tracer. In best case as additional option, not the only behaviour.

...

(?) I have already uploaded a test model to Shapeways... works fine, I only took it though Meshlab & netfabb, no problems...

Nice model BTW Taurus!  

[taurus]

(?) I have already uploaded a test model to Shapeways...

It's just a matter of ease...