I have a scene which renders a board with several objects. Clicking on one of the objects and by use of object picking I can get the object and animate the cameras position to sit in an 'overhead' view of the object. Then using the camera.lookAt method I can force the camera to look directly at the object.
I am noticing a quick jump at the start of my animation when calling camera.lookAt within the onUpdate method as it initially has a large distance to rotate to look at the object selected. Each subsequent call to camera.lookAt is tiny in comparison and is animated nicely.
// Position the camera to fit
var tween = new TWEEN.Tween(camera.position).to({
x: selectedObject.position.x,
y: selectedObject.position.y,
z: 1
}).easing(TWEEN.Easing.Quadratic.InOut).onUpdate(function() {
camera.lookAt(selectedObject.position);
}).onComplete(function() {
camera.lookAt(selectedObject.position);
}).start();
Is there any way to animate the method or will I have to manually transform the matrix values of the camera to look at my selected object?
Here is a fiddle with an example. It uses WebGLRenderer so please use a suitable browser.
http://jsfiddle.net/fungus1487/SMLwa/
Thanks for any help.
One thing you can do is tween both the camera position and the camera target (which you have to define).
const tweenPosition = new TWEEN.Tween( camera.position )
.to( {
x: selectedObject.position.x,
y: selectedObject.position.y,
z: 1
} )
.easing( TWEEN.Easing.Linear.None ).onUpdate( function () {
camera.lookAt( camera.target );
} )
.onComplete( function () {
camera.lookAt( selectedObject.position );
} )
.start();
const tweenTarget = new TWEEN.Tween( camera.target )
.to( {
x: selectedObject.position.x,
y: selectedObject.position.y,
z: 0
} )
.easing( TWEEN.Easing.Linear.None )
.onUpdate( function () {
} )
.onComplete( function () {
camera.lookAt( selectedObject.position );
} )
.start();
It's a little tricky, because the tween's need to run exactly concurrently, and they don't... This is the reason for the camera.lookAt() call in the second tween.