Need help with orientation in PreForm...can anyone explain?

[katkramer]

I have a question…I’ve submitted this in Feature Requests, but it’s something that’s driving me nuts…I’m hoping someone else has figured it out and can explain.

When I bring a model into PreForm, let’s say this object is sitting on its side. However, I cannot for the life of me figure out WHICH BUTTON I use to orient this correctly, with the flat side down in PreForm.

Is there any rhyme or reason to these buttons? Is there a way I can think through this so I can stop using trial and error on every model? Like, “if I’m looking from the “front” at the model as it was brought into PreForm, the icon with the blue square at the back will place the back of my model down?” (In the image, I’ve color-coded, so imagine all of these are blue). Also, the “Select Base” function doesn’t work…I think something with my “normals” is off, but I never have any luck with that feature. I am using ZBrush, so it’s more freeform than a CAD program such as SketchUp or MOI (Moment of Inspiration).

I enclosed the image I mocked up in the Feature Requests section, but it’s only to show how the model came into PreForm. I would assume that the icon in the first position on the second row would choose what’s currently the back and put it facing down, but it doesn’t work that way.

Am I just thinking about this incorrectly? These buttons don’t seem to be related to the current position of the model, but instead about a more permanent orientation, like as if it’s going by the model’s internal axes that we can’t see.
My suggestion was that the orientation “ball” be color coded and that the colors relate somehow to the Orientation box in PreForm.

But until then, I’d love to understand HOW this feature works. It doesn’t waste much time, but I feel like I’m having to do this with every model and after six months I still don’t understand. Thanks!

[Frew]

The issue here does usually have to do with the models ‘internal orientation’. This is a bit more evident when using one of the parametric applications like Solidworks or Fusion360 (not that I’m biased). You can choose which plane to model on and that’s how the orientation of your model is determined.

If your model is oriented such that the ‘base’ is flat against the platform, the buttons react as you might expect and rotate the base towards the highlighted portion. If your model has a more confusing orientation from your design software, the buttons might be a bit more confusing as the base isn’t where you’d expect.

I like the idea of color coding and that might make the axis a bit more obvious. Ultimately, if the base isn’t where you’d intuitively expect, using the buttons may be confusing regardless. I usually iterate through them in that case until I find the correct one.

[katkramer]

@Frew! Our old friend, there you are.

Yes, please pass the color-coding idea along (hint, hint).

I do set an axis in ZBrush, and can turn on a “floor” that indicates that the X axis is running left/right, the Y axis is vertical, and Z is front to back. But bringing that it, the model is always on its side. Maybe I could run a few experiments and figure out which plane ZBrush thinks is the floor? I can tell you that this one came in from MoI (Moment of Inspiration) and it also came in on its side. Hmmmm…maybe a preference could be set according to your software that might orient the model correctly? Like say, I’m bringing in something from ZBrush, and I could go into the preferences on PreForm and “map” my axes to match from that particular program? Then I could have a setting for MoI that would bring its models in with a different axis mapping?

Fusion360 kicks my butt…I want to understand…but I’m a SketchUp girl. I think Solidworks is pretty expensive?

As always, thanks for your replies in the forum! Here is the file if you’d like to try out what I’m describing here. It’s the .form file, and the cube has been imported into PreForm and has not been oriented at all. Google Drive: Sign-in

The dark image below is the view of the cube in ZBrush. The Y axis “floor” is showing at the bottom, and the axes are marked on the cube.

The image below is the view as it is imported into PreForm as a .OBJ file.

After choosing the icon with the “correct base” (the second icon from the first row in the image below), this is the resulting orientation. My thinking in choosing this button is that the back edge/surface on the right is what I want as the base. The result is not what I expected.

As shown below, the correct button is the first one in the first row, but it doesn’t rotate as expected. I would actually expect that it would make the front of the cube (the side to the left with X and Y) line up with the “FRONT” on the grid.

[Frew]

I sent this thread over to our software team

It’s especially tricky in something like Zbrush or MOI because the software may set axis in a non-intuitive way. It looks like this is what you’re seeing with Zbrush as the base isn’t being positioned quite where you’d expect. The parametric programs are a bit easier because you usually have to define the axis whereas everything is a bit more relative in the sculpting suites.

[DavidRosenfeld]

Unless I am mistaken, MOI axis are defined like other parametric CAD programs. ( at least that is how I have MOI setup). ZBrush, I have no idea.

[katkramer]

Frew, I would welcome the opportunity to give them a demo in Google hangouts if that would be helpful.

When you start drawing in ZBrush, the green Y axis is vertical, and the green mesh you see is the Y floor as it sits with the Y axis going up and down. As compared to SketchUp, which has a default of the XY axis (red, green) on the “floor” with the Z axis (blue) going up and down. I would assume that SketchUp qualifies as a parametric modeling program? So that is different.

So maybe the answer is that the user can possibly choose an orientation in the Preferences? Or even a program preference when importing a model? Since ZBrush has been around for almost 20 years, and a lot of people use it for character models that are perfect on the Form 2, it might be helpful for those users to accommodate in some way. It seems like the Preference might be the easiest way to accomplish that.

The import couldn’t be tied to the file extension, since the different programs can export the same file types. I don’t know if behind the scenes PreForm could determine the program type and adjust automatically? I’m not a programmer, but I would think that information is stored in the metadata?

I do know quite a bit about SketchUp, and I know that there is a feature to change the axis setup of an individual component. There are different axes…the main “global” axis orientation, but then each component or group can have its own individual axis orientation that can be viewed and/or changed when you double-click on the component or group.

However, I don’t see any option in ZBrush to do that with an individual “Subtool,” which is roughly the equivalent of a component in SketchUp. I also don’t see anything in the Preferences menu that would allow the user to choose an alternative axis system. I could manually rotate the object and turn on a different “floor” to be on the Z axis, like other drawing programs with the XY green and red axes on the floor…BUT…I think the average person won’t think about something like this.

I see that @DavidRosenfeld has given feedback on MoI’s orientation…I’m very new to MoI so I wasn’t aware I could change a preference to change it…thank you, David.

Here’s the alternate, resulting layout in ZBrush (below)…you can see the green Y axis and red X axis on the floor.

And here is the axis system of a component in SketchUp