[SOLVED] Model breaks when exporting with AnimComposer / SkinningControl

remy_vd · April 5, 2019, 1:09pm

Hi,

I wanted to give the new AnimComposer a try, and I noticed that after running the AnimMigrationUtils.migrate(model)method and saving it, the model ‘breaks’.

The weird thing is, that when you actually play an animation on the broken model, it assembles itself again correct.

This is probably a weird explanation, so I added some screenshots and a test case:

public class AnimComposerErrorTest extends SimpleApplication {

    public static void main(String[] args) {
        new AnimComposerErrorTest().start();
    }

    @Override
    @SneakyThrows
    public void simpleInitApp() {
        Spatial model = assetManager.loadModel("/Models/characters/human/human-all-rigged.j3o");
        AnimMigrationUtils.migrate(model);

        BinaryExporter exporter = BinaryExporter.getInstance();
        exporter.save(model, new File(JmeSystem.getStorageFolder(), "migrated-model.j3o"));

        assetManager.registerLocator(JmeSystem.getStorageFolder().getAbsolutePath(), FileLocator.class);
        Spatial migratedModel = assetManager.loadModel("migrated-model.j3o");

        model.move(-2, 0, 0);
        //SpatialUtils.getFirstControl(model, AnimComposer.class).ifPresent(animComposer -> animComposer.setCurrentAction("idle"));

        migratedModel.move(2, 0, 0);
        //SpatialUtils.getFirstControl(migratedModel, AnimComposer.class).ifPresent(animComposer -> animComposer.setCurrentAction("idle"));

        rootNode.attachChild(model);
        rootNode.attachChild(migratedModel);

        rootNode.addLight(new AmbientLight(ColorRGBA.White.mult(0.3f)));
        rootNode.addLight(new DirectionalLight(Vector3f.UNIT_Y.negate(), ColorRGBA.White));
    }
}

result:

But when I uncomment the lines that start playing an animation it becomes:

The SpatialUtils.getFirstControl() method only does a depth first traversal of the spatial and returns the first control that matches the given type, so no ‘magic’ happens in that method.

Ali_RS · April 5, 2019, 2:19pm

Make suer to add this before exporting original model:

 SkinningControl sk = originalModel.getControl(SkinningControl.class);
 sk.getArmature().saveInitialPose();

or do this on migratedModel :

SkinningControl sk = migratedModel.getControl(SkinningControl.class);
sk.getArmature().applyBindPose();

oxplay2 · April 5, 2019, 2:29pm

this character preferred to be in egg transform he packed himself very good!

remy_vd · April 5, 2019, 3:24pm

Thanks @Ali_RS, that worked!

Could you explain me the difference between bindPose and initialPose?

Ali_RS · April 5, 2019, 3:40pm

I think other folks can explain it more better.

Based on what java doc says:

github.com

jMonkeyEngine/jmonkeyengine/blob/d55776d081770e81df1d2ad65aca3ab7b902c2c1/jme3-core/src/main/java/com/jme3/anim/Armature.java#L204


 * Note that this is only useful for debugging purpose.
 */
public void applyBindPose() {
    for (Joint joint : rootJoints) {
        joint.applyBindPose();
    }
}
/**
 * Saves the current local transform as the initial transform.
 * Initial transform is the one applied to the armature when loaded.
 */
public void saveInitialPose() {
    for (Joint joint : jointList) {
        joint.saveInitialPose();
    }
}
/**
 * Applies the initial pose to this armature
 */

Bind Pose (T-Pose)

github.com

jMonkeyEngine/jmonkeyengine/blob/d55776d081770e81df1d2ad65aca3ab7b902c2c1/jme3-core/src/main/java/com/jme3/anim/Armature.java#L193


public void saveBindPose() {
    //make sure all bones are updated
    update();
    //Save the current pose as bind pose
    for (Joint joint : jointList) {
        joint.saveBindPose();
    }
}
/**
 * This methods sets this armature in its bind pose (aligned with the mesh to deform)
 * Note that this is only useful for debugging purpose.
 */
public void applyBindPose() {
    for (Joint joint : rootJoints) {
        joint.applyBindPose();
    }
}
/**
 * Saves the current local transform as the initial transform.

sgold · April 5, 2019, 5:00pm

I believe bind pose is the state of the model when no animation is applied: all bone/joint transforms set to identity, no morphs applied, and so on. Bind pose might be a T pose or a Y pose or something else entirely, depending on how the model was created.

As the documentation says, initial pose is the state when the model is loaded from assets.

In JME 3.2, bind pose and initial pose were always the same. I’m unsure why @nehon created the distinction.

remy_vd · April 5, 2019, 5:25pm

Ok, thanks. I indeed didn’t get the difference between bind pose and initial pose.