Making consecutive scene.pick calls results in some unpredictible behavior

[hamza-hajji]

Describe the bug Making consecutive calls to scene.pick leads to some unpredictible results To Reproduce Steps to reproduce the behavior:

1. Make a scene.pick call with canvasPos
2. Make another pick using origin/direction

I added the following code to the example xkt_vbo_Duplex.html

let trigger = false;

viewer.scene.input.on("mousedown", (coords) => {
  const hit = viewer.scene.pick({
    canvasPos: coords,
    pickSurface: true,
  });
   
  // trigger to mousemove to start dragging  
  if (hit) {
    trigger = true;
    viewer.cameraControl.active = false;
  }
});

viewer.scene.input.on("mouseup", () => {
  // trigger to mousemove to stop dragging
  trigger = false;
  viewer.cameraControl.active = true;
});

viewer.scene.input.on("mousemove", (coords) => {
  // first hit to determine point A
  const hit = viewer.scene.pick({
    canvasPos: coords,
    pickSurface: true,
  });

  if (!hit || !trigger) return;

  // second I use the first hit's normal as direction and worl position as origin
  // this is supposed to pick the point facing the first point A  
  const otherHit = viewer.scene.pick({
    origin: hit.worldPos,
    direction: hit.worldNormal,
    pickSurface: true,
  });

  // annotations to make the hit points clear
  annotations.createAnnotation({
    id: "myAnnotation" + Object.keys(annotations.annotations).length,
    worldPos: hit.worldPos,
    markerShown: true,
    labelShown: true,
    values: {
      glyph: "A",
      title: "My Annotation",
      description: "This is my annotation.",
    },
  });

  if (otherHit) {
    annotations.createAnnotation({
      id: "otherAnnotation" + Object.keys(annotations.annotations).length,
      worldPos: otherHit.worldPos,
      markerShown: true,
      labelShown: true,
      values: {
        glyph: "B",
        title: "My Annotation",
        description: "This is my annotation.",
      },
    });
  }
});

I made a recording of the behavior when I drag my mouse

Expected behavior I see an annotation A then another annotation B in the opposite direction.

Screenshots

First test: when nothing is facing the first hit point (A), point A is affected making its hit.worldPos null

Second test: when there is a facing wall to the first hit point (A), the first point is wrong but the second is correct (on the roof)

https://imgur.com/a/xfuhefa

Additional context I'm trying to implement moving models (Sphere in the sketch) while dragging my mouse so I pick first with canvasPos to determine where my mouse is and move the model using model.position = hit.worldPos which moves its center. Then I pick using origin/direction in order to calculate the distance between the center and surface of the model in order to snap it to nearest surface.