MorphControl doesn't override cloneFields(), jmeClone(), read(), nor write()

[stephengold]

As was pointed out at the Forum, the MorphControl class supposedly implements JmeCloneable and Savable, yet none of the relevant methods are overridden.

https://hub.jmonkeyengine.org/t/issue-with-multiple-models-and-morph-animations/44598

Obviously this makes it impossible to load a MorphControl from assets.

Also, the OP reported that after cloning a model with a MorphControl, the clone and the original morphed in synchrony.

In my own tests, cloning a model with a MorphControl resulted in a crash:

RendererException: Cannot recompile shader source

[Arkmut]

To clarify, In my test it was more an issue of having only one of the 2 models doing the animation. (I'll edit the forum post for clarity)

[capdevon]

Hi stephen, a little tip:
the MorphControl class extends AbstractControl. The controlUpdate and controlRenderer methods are not invoked if the controller is disabled. So checking if the controller is enabled in such methods is useless right? You could remove these instructions:

public class MorphControl extends AbstractControl {

@Override
protected void controlUpdate(float tpf) { 
    if (!enabled) { // this check is useless
        return;
    }

....
}

@Override
protected void controlRender(RenderManager rm, ViewPort vp) {
    if (!enabled) { // this check is useless
        return;
    }

...
}

[stephengold]

You're quite right.

[Ali-RS]

By the way, we can move this code

jmonkeyengine/jme3-core/src/main/java/com/jme3/anim/MorphControl.java

Lines 79 to 82 in 226176b

	// gathering geometries in the sub graph.
	// This must be done in the update phase as the gathering might add a matparam override
	targets.clear();
	this.spatial.depthFirstTraversal(targetLocator);

into setSpatial() method and remove the controlUpdate() method.

    @Override
    public void setSpatial(Spatial spatial) {
        super.setSpatial(spatial);

        // gathering geometries in the sub graph.
        // This must be done in the update phase as the gathering might add a matparam override
        targets.clear();
        if (spatial != null) {
            spatial.depthFirstTraversal(targetLocator);
        }
    }

Tested it on a bunch of different models and can confirm that works fine.

To clarify a bit more on this comment:
// This must be done in the update phase as the gathering might add a matparam override

In another word, If that runs in the render phase it might throw an exception if a MatParamOverride is added here.

jmonkeyengine/jme3-core/src/main/java/com/jme3/anim/MorphControl.java

Line 391 in 226176b

geom.addMatParamOverride(nullNumberOfBones);

This is the exception message

java.lang.IllegalStateException: Scene graph is not properly updated for rendering.
State was changed after rootNode.updateGeometricState() call. 
Make sure you do not modify the scene from another thread!

For more details see: https://hub.jmonkeyengine.org/t/morphcontrol-question/44599

[Ali-RS]

And this line

jmonkeyengine/jme3-core/src/main/java/com/jme3/anim/MorphControl.java

Line 90 in 226176b

for (Geometry geom : targets) {

should be updated to

for (Geometry geom : targets.getArray())

Edit:

In case you agree I can submit a new patch to settle them all in another PR after #1549 is merged :)

Regards

[stephengold]

A 2nd PR sounds to me like a good plan.

[stephengold]

Okay, @Ali-RS. It's your turn now!