Approximating soft body collision in Hexagon?

Uthgard

Hi, I am a complete and utter neophyte when it comes to modeling, so I don't even know if I am asking the right questions, please bear with me.

 

Thing is, I've had a martial arts project in the backburner for a long time and one of the things lacking in the images is the way bodies react to being hit, grasped or otherwise touched, so I was wondering what's the best way to go about it with morphs. Can I, for instance, take the fist of a figure and use it as a brush to mold another figure stomach? Should I select a number of faces and pull them straight out between grasping fingers? Is there a substantial difference between doing this for two figures interacting and for a single figure touching itself? Any suggestions are appreciated.

Hermit Crab

Hexagon has displacement tools which I only tried using once before and again a couple of minutes ago to try to answer, but I am no expert.

The tools involve using a brush to 'paint' over the mesh - the denser the mesh the better. 

Physics collisions between objects are something else altogether.  Physics simulations take place over time. The program will calculate the changes in position of the objects in the simulation and try to detect collisions between them (or their parts - vertices, edges, faces).  Hexagon has no physics engine, however, so none of that applies here.

Hexagon can be used to create morphs, I believe, but no new geometry can be added to a morph - no vertices of the object being morphed can be deleted.

I attach a picture of a very dense cube mesh which I've altered with the displacement brush.

 

Uthgard

Thanks for the tip, and pardon my ignorance; does the displacement tool just affect the mesh or does it create a displacement map? If it's the second, it may not be a viable solution for Iray. From what you are telling me, I am guessing boolean operations (which sound like a natural starting point for intersecting meshes) aren't the way to go, why? Do they affect the mesh in a way that doesn't allow a morph to transfer? Anyways, thanks again, I'll start experimenting and hope I don't break anything important.

Wee Dangerous John

Are you talking about taking a DAZ character and (for example) pulling a piece of skin, pinching itself ?

Send your character from DAZ Studio to Hexagon using the bridge, then with Soft Selection enabled (adjust strength to suit) select a face(s) on character and pull out.

Displacement Tool is moving the mesh.

Uthgard

Yes, exactly, but also having a character grab another character's face. I am guessing there's no shortcut to use the hand to push the corresponding faces?

Edit: Tried soft selection and the various UV & Paint tools. Whoa, this modeling thing just got about twenty times more intuitive, thanks for the tips.

Wee Dangerous John

I have not tried it myself, but there is an option to create your own Alpha Mask in the Paint tools Properties tab.

Hermit Crab

Uthgard, the displacement tool affects the mesh.  I don't think Hexagon exports displacement maps - but I haven't access to the manual at the moment.

There is an Export Bump tool but I haven't figured how to use it in the brief moments I had to look at it.  For what it's worth, I tried sub-dividing after using these tools on a mesh and Hexagon crashed.  So from that one instance maybe I would advise doing any sub-dividing before using displacement (but obviously not on objects brought into Hexagon for morphs creation).

Again, Hexagon can't take one object and make an impression or indentation on a second object.  Carrara detects collision between objects but if the object doing the colliding is moved further then it springs out at the other side.  It takes a physics engine to do what you suggest.  You could attempt to make your own displacement brush to resemble fingertips perhaps but, again, I haven't the manual to hand to know if this is possible.

(Physics calculations involve assigning properties to meshes so that they behave like hard objects, such as billiard balls, or soft materials such as silk.  As said before, the simulation takes place over time, as in the frames of an animation).

Uthgard said:

Thanks for the tip, and pardon my ignorance; does the displacement tool just affect the mesh or does it create a displacement map?

Uthgard

Again, thanks for the answers and hints. I see that for a generic handprint (for instance) I may be able to render an alpha mask using Iray's depth canvas and use it as a displacement brush, but for almost anything else, I would be better off sculpting custom fit morphs--the soft selection tool really is a lifesaver in that regard. At least, this has been a good way to get me over my modelling phobia, I was completely convinced I would manage to utterly wreck things one way or another

Morkonan

Just a note on creating Alpha Masks with Hexagon -

1) Don't forget that the mask is going to be at the resolution set for your UVMap. That can present some difficulties for fine-detail masks as Hex's mapping exports leave a little to be desired. But, in any event, set it as large as necessary.

2) And, don't forget, the brushes that use their own maps are static-resolution maps. They're not truly dynamic. So, for instance, if you want to cover a large area with really detailed Alpha Map Brush, you'll have to make your own map and add it to the appropriate directory or use the already smaller, included maps, over and over until you get the coverage you want. (Can't remember, but it's not terribly difficult.)

PS - I don't use Hex's Alpha map/mask brushes often and, when I do, it's only for references I can use in other programs.