Custom render pass / always render on top

Troubleshooting graphics
1

Hi all,



I have an object that I would like to always render on top of the other objects (but not the GUI).



So, even if this object is hidden behind a building, or under water, or in cave, it will still be seen. I was planning to do this by drawing the entire scene, and then rendering the object afterwards.



I have the object set up as a Node, but I can’t seem to get it work. I tried using renderManager.renderScene() after the regular render, but to avail



Can anyone shed some light on how to add my own render pass to do this?



Thanks very much

2

The best way is to setup a custom ViewPort.

Something like:

[java]

Node root = new Node( "Overlay Root" );

root.setCullHint(CullHint.Never);

Camera overlayCam = app.getCamera().clone();

overlayCam.setLocation( new Vector3f(0, 0, 10) );

…etc…

ViewPort view = app.getRenderManager().createMainView("Overlay", overlayCam);

view.setClearFlags(false, true, false);

view.attachScene( root );

[/java]

Then you just have to remember to call these on update() (or render()):

[java]

root.updateLogicalState(tpf);

root.updateGeometricState();

[/java]

I do mine in an AppState so I do the updateLogicalState() call in AppState.update() and the updateGeometricState() in AppState.render().

3

What if you disable depth checking for that object?

4

Ooop… I assumed the object was more complicated than a convex shape and that it might rotate. InShadow is right, though. If you have a simple convex shape and/or a shape that won’t self-occlude when it rotates then you should be able to get away with turning depth testing off.

5

Thank you pspeed. Your solution was exactly what I was looking for :slight_smile:



It’s lucky, because I am not sure how to disable depth checking for an object haha

6

In case it comes up in the future: material.getAdditionalRenderState().setDepthTest(false)