Milkshape Model

Troubleshooting graphics
1

Well, I got a milkshape model loaded with materials and all, things are still VERY rough, so I’m not going to be committing it for a bit longer. But just thought I’d show a teaser, the model loaded with a light running around it.



2

wel…im feeling two fold!! :smiley: for seeing a model again in jME and :frowning: for not being able to use it yet!!

3

Ok, getting closer. Model is being loaded and set to a TriMesh now. Having a bit of an issue with bounding volumes. The model is being culled at times when it should still be visible.

4

Does anyone have any milkshape ASCII models? All I have is the one in the demo and I need to test against multiple. Please let me know!

5

Ok, initial check in of the milkshape loader is in:



com.jme.scene.model.MilkshapeASCIIModel



test is com.jme.renderer.TestMilkshapeASCII



No animations yet. Still trying to figure out how to handle that in terms of controllers, etc.



VERY little testing done, I am without models. Please, please use all the models you can and let me know if it blows up on something.



This is a very rough cut, has a bit of a ways to go. But it should give you guys an idea on how the loaders will work.



Basically:



Node modelScene = MyModelLoader.load(“Model”);



that easy.



Each component of the model is it’s own Node/TriMesh group. Meaning the model is automatically placed into a tree and individual sections can be culled. This is important for very large models where you might only see a small section at a time.



Which leads me into my next topic…



Custom loader.



I want to make a custom format for jME. It will be XML based, and allow the loading of a model. But the model can be any size, in fact, an entire scene in desired. I need people who are good with XML and parsing.



I’d also love to be able to save a scene (at any level) as this custom format.



Then sometime in the future maybe write a Milkshape 3D importer/exporter, so you can work on the custom models in that tool.

6

can i assume that i can call model.setLocalTranslation(Vector3f) to set the model’s location?

7

Yes, you’d do something like:



//Get model
Node soldier = MilkshapeASCIILoader.load("data/model/msascii/run.txt");
soldier.setLocalTranslation(soldierPosition);
soldier.setLocalRotation(soldierRotation);



You can treat it like you would any other node.
8

do you have an article or something for me to learn about Quateranian (or something similar, excuse the spelling)?



because you need that for rotations dont you?

9

There is already a Quaternion class in com.jme.math. It was requested for the ODE physics stuff. So you can look there for an implementation. If you want to learn about it, there are a few math books out there that have good articles about it.



I think the first lesson I took was probably this:



http://www.gamedev.net/reference/articles/article1095.asp



then I read about it in various books.



So, the Quaternions are there for the slerping (spherical linear interpolation), which allows the joints to rotate smoothly. I just need to set up the keyframes/joints and inverse kinematic system.

10

kewlies, i just want to know how can I rotate my models with it?

11
kewlies, i just want to know how can I rotate my models with it?


Node rotations are via Matrix3f. You can create quaternion rotations and convert to Matrix3f. For creating rotations via Quaternions look at:

fromAngles(float[]). Takes 3 float values (3 angles (x,y,z)). So if you wanted to rotate 30 degrees on x, 45 on y, and 0 on z.

float angles[] = {30,45,0};
quaternion.fromAngles(angles);
node.setLocalRotation(quaternion.toRotationMatrix());

fromAngleAxis(float, Vector3f) allows you to define an axis to rotate about and an angle to rotate. So if I wanted to rotate 30 degrees about the (1,1,1) axis:

quaternion.fromAngleAxis(30, new Vector3f(1,1,1));

You can also "slerp" between two quaternions to allow for smooth rotations.

Let say you have a quaternion (q1) of the models current orientation, and have a destination rotation (q2). You can find any quaternion between q1 and q2 (q1 == 0, and q2 == 1).

float amount = timePassed / timeForRotation;
Quaternion currentQ = q1.slerp(q1,q2,amount);

Let me know if you need any more info.
12

Also, I suppose I am going to go ahead and keep working with MilkshapeASCIILoader and get animations working. My original plan was to get all the loaders loading static models first then hit animation, but I might as well get one loader all the way complete first.