Sunday, April 1, 2018

Brandon Wehenkel: Independent Study (Update 3)


The purpose of this study here, for a turntable, go here.


I need to make the file 3D printer friendly, which has taken all four weeks.  Still behind but slowly getting things done.  My goal for this session was to create keys for all of my geometry so I can finalize my file for printing and make my goal for removable parts valid.  The biggest problem is that it took ages to do anything because Maya crapped on me every place I tried.  At home, in the lab, and in the student lab on the 2nd floor; my personal computer was much faster than all other locations, and it was a snail’s pace. I tried Zbrush to clean up the hole but I am all too uninformed on the application, so it was not very helpful this time around.  I will need to know how to use that application when I want to do this process again,
Problem 1:
First thing to mention, as I was working on transferring data from Mudbox to Rhino back and forth, I came across a minor issue with Rhino increasing the size of all the .obj imports.  I discovered that 500k polys for the body and sitting figure are still too much.  Rhino craps out when the objects are booleaned or trimmed in any way.  So I had to go back into Mudbox to decimate again.  The torso, legs, and sitting figure are below 150K polys.  The arm is at 70k polys.



Cutting reference


Problem 2:

Working in Maya is slow!!!  Imagine doing append a poly once every 17 minutes, and you have to repeat the command 46 times. I needed to cut the models in parts to fit the 3D printer.  What I discovered was that Rhino and Mudbox do not fill holes very well.  Rhino's hole fill tool does not clean the topography when applied. It creates triangles with a lot of connecting points in the middle creating an ugly seam and pinches the geometry when required to extrude.  When importing into Mudbox after modeling in Rhino creates multiple overlapping layers with holes as well as jacks up the topography when cleaned with the patch tool, making it not worth my time.  So I was stuck in Maya to fix this problem.  After spending about 3 hours and only appending 16 faces out of 46, I had to think of something else.  Maya has a fill hole tool as well, it only does half the work, unfortunately, requiring the use of the interactive split toolExtrude took 2 hours at most for some locations on the arm.   Hole fill takes 3 hours to complete.





From 11:50 am Sunday, March 26 to 3:26 am Monday, March 27th I appended one polygon.  I do not know what the problem is but Maya does not like my arm mesh.  Saving, restarting the computer cleaned up some of this wait time.



 MUDBOX HOLES


Referring to what I mentioned earlier, after working in Rhino and importing back into Mudbox.  The .obj creates holes in the topography and recreates topography errors denoted by the red dots.  The black texture problems around the fingers were not being picked up as errors but were in fact errors.  Every black section is a hole where the geometry is overlapping.  I did not continue to work with this mess.  I returned to Maya and used filled holes to start the key instead.



A part of problem 2, I needed to create a key, but the program took ages even to get this far.  This took 3 hours to get this far.  Restarting the computer managed to alleviate the time issue, but it still took about 4-20 minutes per each append poly/ insert edge loop/ interactive split tool/ merge vertex command.


Modeling Techniques:


The very first thing I had to do was cut all the pieces in the way I wanted.  I used all three programs, Rhino, Mudbox, and Maya to make these cuts.  I figured out that Maya was the more accurate program to do these cuts.



Photo of all cut pieces.


Cutting took about two weeks, unfortunately. How do you ask? It seemed like a simple task, but I needed to go back and forth between Mudbox and Rhino to see the parts and how they aligned up.  I would cut then fix the geometry, revert then cut again, fix the geometry, then revert and it took about three days to do that for the torso alone. I had to align the files overlapping each other till I found the most accurate place to slice.  It was a bit annoying for me because in real life you could pick up the objects and place them where you wanted.  In the 3d view window there isn't resistance when overlapping, so parts such as the fingers would be intersecting in the hooves while the other half of the geometry would be perfectly aligned in the arm.  It took much finesse to find the right spot.  I saved the perfect alignment pieces as an.Obj and imported it into Mudbox to clean up the geometry again, so that the seams were cleaner for cutting.The most straightforward part to cut was the arm.  However, it still was annoying because the geometry from my sculpted object is not completely round.  I fixed it as best as I could, but there's still some post work I will need to do with my Dremel tool hopefully in April.


Problem 3:

Rhino does not like the number of polys I have in one file so doing any modeling was terrible.  I tried to do boolean commands, but nothing worked how I wanted.  Most of the commands froze and crashed the program.


Mudbox created holes, third photo above.


In Maya, I used the interactive split tool and split polygon tool with edge selection turned on to cut the objects. I used the splitting objects & detaching commands to make the program know its two different objects.  Unlike Rhino when you use a boolean (to do the same process), Maya still thought the objects were the same, so I needed to delete the history for it to forget the changes.


I watched a video on youtube for making keys (pegs for the models to interlock) in Zbrush and used some of that knowledge for making it in Maya.  I would be better off in ZBrush, based on the struggles I have had so far.  I needed to make keys for my models.  I started with the smallest polygonal mesh (70k), the arm, on 22 March, four days later it still wasn't finished.



 The highlighted poly took 3 hours to create, 
and the geometry still looks like garbage.


I used extrude tool to begin the peg. I used the interactive split tool, append a poly, and merge tool to create the skeleton of the peg.  The topography was not right by 11:50 am Sunday, March 26.  Moreover, as of 5:28 Monday, March 27 the shape, direction, and topography of the peg has changed minimally.  The whole process is not worth the wait in Maya.
After completing the key for the arm, I have to repeat the process for the torso. Then I can invert the geometry scale it slightly and insert it into the holes of the arm (of the legs geometry) and sitting/legs portion.  Not sure exactly what the problem is regarding why everything is so slow because nothing is more significant than 150K polys.  Does Maya not like that many polys?



 Problem 4:
As of 4/2/18 12:08am, just as I thought I could continue to the next step of my process (making inverse keys) I find this odd colored geometry intersecting the eye and ear.  This wasn't here before when I was working in mudbox.  All these .obj conversions between mudbox, maya, and Rhino really screw things up. Deleting the colored mess creates boundary errors.  I gotta figure out how to quickly close open boundaries in MayaEdge merge doesn't seem to work for me.


What I have left regarding printing is to create an inverted key for the other parts

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