update method
dynamic
update()
Implementation
update() {
var position = scope.object.position;
offset.copy(position).sub(scope.target);
// rotate offset to "y-axis-is-up" space
offset.applyQuaternion(quat);
// angle from z-axis around y-axis
spherical.setFromVector3(offset);
if (scope.autoRotate && state == State.none) {
rotateLeft(getAutoRotationAngle());
}
if (scope.enableDamping) {
spherical.theta += sphericalDelta.theta * scope.dampingFactor;
spherical.phi += sphericalDelta.phi * scope.dampingFactor;
} else {
spherical.theta += sphericalDelta.theta;
spherical.phi += sphericalDelta.phi;
}
// restrict theta to be between desired limits
var min = scope.minAzimuthAngle;
var max = scope.maxAzimuthAngle;
if (isFinite(min) && isFinite(max)) {
if (min < -Math.pi) {
min += twoPI;
} else if (min > Math.pi) {
min -= twoPI;
}
if (max < -Math.pi) {
max += twoPI;
} else if (max > Math.pi) {
max -= twoPI;
}
if (min <= max) {
spherical.theta = Math.max(min, Math.min(max, spherical.theta));
} else {
spherical.theta =
(spherical.theta > (min + max) / 2) ? Math.max(min, spherical.theta) : Math.min(max, spherical.theta);
}
}
// restrict phi to be between desired limits
spherical.phi = Math.max(scope.minPolarAngle, Math.min(scope.maxPolarAngle, spherical.phi));
spherical.makeSafe();
spherical.radius *= scale;
// restrict radius to be between desired limits
spherical.radius = Math.max(scope.minDistance, Math.min(scope.maxDistance, spherical.radius));
// move target to panned location
if (scope.enableDamping == true) {
scope.target.addScaledVector(panOffset, scope.dampingFactor);
} else {
scope.target.add(panOffset);
}
offset.setFromSpherical(spherical);
// rotate offset back to "camera-up-vector-is-up" space
offset.applyQuaternion(quatInverse);
position.copy(scope.target).add(offset);
scope.object.lookAt(scope.target);
if (scope.enableDamping == true) {
sphericalDelta.theta *= (1 - scope.dampingFactor);
sphericalDelta.phi *= (1 - scope.dampingFactor);
panOffset.multiplyScalar(1 - scope.dampingFactor);
} else {
sphericalDelta.set(0, 0, 0);
panOffset.set(0, 0, 0);
}
scale = 1;
// update condition is:
// min(camera displacement, camera rotation in radians)^2 > EPS
// using small-angle approximation cos(x/2) = 1 - x^2 / 8
if (zoomChanged ||
lastPosition.distanceToSquared(scope.object.position) > eps ||
8 * (1 - lastQuaternion.dot(scope.object.quaternion)) > eps) {
scope.dispatchEvent(_changeEvent);
lastPosition.copy(scope.object.position);
lastQuaternion.copy(scope.object.quaternion);
zoomChanged = false;
return true;
}
return false;
}