hitTest doesn't work

[agGitHub]

Hi,

In the following sample:

https://github.com/SceneView/sceneform-android/blob/master/samples/3d-model-viewer/src/main/java/com/google/ar/sceneform/samples/sceneviewbackground/MainActivity.java (3D viewer without ARCore)

I removed the backgroundSceneView in order to keep only the transparentSceneView in full screen.

Then, I do (in a onFrameUpdate loop):

Scene scene = transparentSceneView.getScene();
Camera camera = scene.getCamera();
Ray ray0 = camera.screenPointToRay(halfScreenWidth, halfScreenHeight); 
 ArrayList<HitTestResult> list =  scene.hitTestAll(ray0);

ray0 equals: [Origin:[x=0.0, y=4.543066E-6, z=-0.01], Direction:[x=0.0, y=4.5430654E-4, z=-0.9999999]] => seems correct

hitTestAll gives the following point: [x=0.0, y=4.543066E-6, z=-0.01] => seems not correct as the model backdrop.glb is located at position (0,0,-1).

Is there any bug with hitTest? Or am I missing something?

Thanks.

[ThomasGorisse]

The HitTest in a 3D only context will return something only if it hit something (a Node). What are you trying to achieve?

[ThomasGorisse]

Sorry. I didn't read your question fully. I will have a look at it since it's one of the next goal for SceneView. You should give a try to Filament Pick API which you should be able to use within Sceneform and which will replace 3D (non AR) actual hitTest in SceneView

[ThomasGorisse]

While speaking about hitTest, just to let you and others know, in SceneView, we have made the choice to use the ARCore depth hitTest instead of the DepthLab way: own hitTest system based on the Depth Image. So the Filament Pick API will be the only one available for 3D only usage.

@agGitHub Please let us know your results if you give a try with the Filament Pick API and link question you could ask them here.

[agGitHub]

Thanks for your answers. Actually, it seems that the problem was due to the backdrop.glb model. For some reasons, it doesn't respond to raycast/hittest. Perhaps because it seems to have no texture or a transparent texture (it is covered with the typical 'checkerboard' texture of the 'alpha color'). Or perhaps another bug on this glb model. I imported a GLTF model and it works. Will tell you if I have new info.

[agGitHub]

I confirm that it is a bug due to backdrop.glb (probably because it has a kind of transparent texture), not due to the glb format. Indeed, I just tested hittest with the other glb model present in your sample (dragon.glb) ; it has a texture, and it receives hittests correctly.