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I'm making a model of the Solar System. This is my current metric:

scale = 0.001;
// 1 unit - 1 kilometer
var AU = 149597871 * scale;

This is how i define the camera, renderer and controls:

camera = new THREE.PerspectiveCamera(70, window.innerWidth / window.innerHeight, 0.1 * scale, 0.1 * AU);
renderer = new THREE.WebGLRenderer({ alpha: true, antialias: true });
controls = new THREE.OrbitControls(camera, renderer.domElement);

Then i give the user the option to jump between the objects so this is how i set the camera after user selects a planet/moon: 

function cameraGoTo() {
    for (var i = scene.children.length - 1; i >= 0 ; i--) {
        var obj = scene.children[i];
        if (obj.name == parameters.selected) {
            controls.target = obj.position;
            camera.position.copy(obj.position);
            camera.position.y += obj.radius * 2;
        }
    }
}

The problem is that for small planets/moons ( <= 1000 km in radius) camera is shaking while rotating around the object. I have only basic knowledge of computer graphics so i don't know either this is the problem of Orbit Controls or it has something to with renderer itself...so I've tried to set logarithmicDepthBuffer = true but it didn't help. Also trying different scale didn't change anything.

Thank in advance for any help/clues.

EDIT:

Here's the fiddle: http://jsfiddle.net/twxyz/8kxcdkjj/

You can see that shaking increases with any of the following:

  • the smaller the object,
  • the further the object from the point of origin,

What is the cause of this? It clearly seems it has nothing to do with the camera near/far spectrum values but is related to the distance the objects are from the center of the scene.

tomi.lee.jones
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  • See http://stackoverflow.com/questions/26049182/mouse-coordinates-irrelevant-after-zooming-is-it-bug/26090323#26090323 – WestLangley Jan 18 '15 at 17:34
  • Unfortunately reducing the range between camera's near and far plane doesn't help. I set NEAR to 0.01 and FAR to 1 (so the range is only 10^2) and shaking still happens. – tomi.lee.jones Jan 18 '15 at 17:56

1 Answers1

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I've come up with the solution.

My problem was with the floating point precision errors when dealing with objects far from the point of origin. This turns out to be a very known problem and there are various solutions. I've used this one:

http://answers.unity3d.com/questions/54739/any-solution-for-extreamly-large-gameworlds-single.html

What happens is basically instead of moving the camera/player, we transform whole scene relative to the camera/player that is always at the point of origin. In this case, Orbit Controls' target is always point of origin.

tomi.lee.jones
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