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import compose from "./compose.js";
import {abs, asin, atan2, cos, degrees, pi, radians, sin, tau} from "./math.js";
function rotationIdentity(lambda, phi) {
if (abs(lambda) > pi) lambda -= Math.round(lambda / tau) * tau;
return [lambda, phi];
}
rotationIdentity.invert = rotationIdentity;
export function rotateRadians(deltaLambda, deltaPhi, deltaGamma) {
return (deltaLambda %= tau) ? (deltaPhi || deltaGamma ? compose(rotationLambda(deltaLambda), rotationPhiGamma(deltaPhi, deltaGamma))
: rotationLambda(deltaLambda))
: (deltaPhi || deltaGamma ? rotationPhiGamma(deltaPhi, deltaGamma)
: rotationIdentity);
}
function forwardRotationLambda(deltaLambda) {
return function(lambda, phi) {
lambda += deltaLambda;
if (abs(lambda) > pi) lambda -= Math.round(lambda / tau) * tau;
return [lambda, phi];
};
}
function rotationLambda(deltaLambda) {
var rotation = forwardRotationLambda(deltaLambda);
rotation.invert = forwardRotationLambda(-deltaLambda);
return rotation;
}
function rotationPhiGamma(deltaPhi, deltaGamma) {
var cosDeltaPhi = cos(deltaPhi),
sinDeltaPhi = sin(deltaPhi),
cosDeltaGamma = cos(deltaGamma),
sinDeltaGamma = sin(deltaGamma);
function rotation(lambda, phi) {
var cosPhi = cos(phi),
x = cos(lambda) * cosPhi,
y = sin(lambda) * cosPhi,
z = sin(phi),
k = z * cosDeltaPhi + x * sinDeltaPhi;
return [
atan2(y * cosDeltaGamma - k * sinDeltaGamma, x * cosDeltaPhi - z * sinDeltaPhi),
asin(k * cosDeltaGamma + y * sinDeltaGamma)
];
}
rotation.invert = function(lambda, phi) {
var cosPhi = cos(phi),
x = cos(lambda) * cosPhi,
y = sin(lambda) * cosPhi,
z = sin(phi),
k = z * cosDeltaGamma - y * sinDeltaGamma;
return [
atan2(y * cosDeltaGamma + z * sinDeltaGamma, x * cosDeltaPhi + k * sinDeltaPhi),
asin(k * cosDeltaPhi - x * sinDeltaPhi)
];
};
return rotation;
}
export default function(rotate) {
rotate = rotateRadians(rotate[0] * radians, rotate[1] * radians, rotate.length > 2 ? rotate[2] * radians : 0);
function forward(coordinates) {
coordinates = rotate(coordinates[0] * radians, coordinates[1] * radians);
return coordinates[0] *= degrees, coordinates[1] *= degrees, coordinates;
}
forward.invert = function(coordinates) {
coordinates = rotate.invert(coordinates[0] * radians, coordinates[1] * radians);
return coordinates[0] *= degrees, coordinates[1] *= degrees, coordinates;
};
return forward;
}
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