Methods
static Cesium.Transforms.computeFixedToIcrfMatrix(date, result) → Matrix3
Computes a rotation matrix to transform a point or vector from the Earth-Fixed frame axes (ITRF)
to the International Celestial Reference Frame (GCRF/ICRF) inertial frame axes
at a given time. This function may return undefined if the data necessary to
do the transformation is not yet loaded.
Name | Type | Description |
---|---|---|
date |
JulianDate | The time at which to compute the rotation matrix. |
result |
Matrix3 | optional The object onto which to store the result. If this parameter is not specified, a new instance is created and returned. |
Returns:
The rotation matrix, or undefined if the data necessary to do the
transformation is not yet loaded.
Example:
// Transform a point from the ICRF axes to the Fixed axes.
const now = Cesium.JulianDate.now();
const pointInFixed = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const fixedToIcrf = Cesium.Transforms.computeIcrfToFixedMatrix(now);
let pointInInertial = new Cesium.Cartesian3();
if (Cesium.defined(fixedToIcrf)) {
pointInInertial = Cesium.Matrix3.multiplyByVector(fixedToIcrf, pointInFixed, pointInInertial);
}
See:
static Cesium.Transforms.computeIcrfToFixedMatrix(date, result) → Matrix3
Computes a rotation matrix to transform a point or vector from the International Celestial
Reference Frame (GCRF/ICRF) inertial frame axes to the Earth-Fixed frame axes (ITRF)
at a given time. This function may return undefined if the data necessary to
do the transformation is not yet loaded.
Name | Type | Description |
---|---|---|
date |
JulianDate | The time at which to compute the rotation matrix. |
result |
Matrix3 | optional The object onto which to store the result. If this parameter is not specified, a new instance is created and returned. |
Returns:
The rotation matrix, or undefined if the data necessary to do the
transformation is not yet loaded.
Example:
scene.postUpdate.addEventListener(function(scene, time) {
// View in ICRF.
const icrfToFixed = Cesium.Transforms.computeIcrfToFixedMatrix(time);
if (Cesium.defined(icrfToFixed)) {
const offset = Cesium.Cartesian3.clone(camera.position);
const transform = Cesium.Matrix4.fromRotationTranslation(icrfToFixed);
camera.lookAtTransform(transform, offset);
}
});
See:
static Cesium.Transforms.computeTemeToPseudoFixedMatrix(date, result) → Matrix3
Computes a rotation matrix to transform a point or vector from True Equator Mean Equinox (TEME) axes to the
pseudo-fixed axes at a given time. This method treats the UT1 time standard as equivalent to UTC.
Name | Type | Description |
---|---|---|
date |
JulianDate | The time at which to compute the rotation matrix. |
result |
Matrix3 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix3 instance if none was provided.
Example:
//Set the view to the inertial frame.
scene.postUpdate.addEventListener(function(scene, time) {
const now = Cesium.JulianDate.now();
const offset = Cesium.Matrix4.multiplyByPoint(camera.transform, camera.position, new Cesium.Cartesian3());
const transform = Cesium.Matrix4.fromRotationTranslation(Cesium.Transforms.computeTemeToPseudoFixedMatrix(now));
const inverseTransform = Cesium.Matrix4.inverseTransformation(transform, new Cesium.Matrix4());
Cesium.Matrix4.multiplyByPoint(inverseTransform, offset, offset);
camera.lookAtTransform(transform, offset);
});
static Cesium.Transforms.eastNorthUpToFixedFrame(origin, ellipsoid, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame with an east-north-up axes
centered at the provided origin to the provided ellipsoid's fixed reference frame.
The local axes are defined as:
- The
x
axis points in the local east direction. - The
y
axis points in the local north direction. - The
z
axis points in the direction of the ellipsoid surface normal which passes through the position.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.
Example:
// Get the transform from local east-north-up at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const transform = Cesium.Transforms.eastNorthUpToFixedFrame(center);
static Cesium.Transforms.fixedFrameToHeadingPitchRoll(transform, ellipsoid, fixedFrameTransform, result) → HeadingPitchRoll
Computes heading-pitch-roll angles from a transform in a particular reference frame. Heading is the rotation from the local north
direction where a positive angle is increasing eastward. Pitch is the rotation from the local east-north plane. Positive pitch angles
are above the plane. Negative pitch angles are below the plane. Roll is the first rotation applied about the local east axis.
Name | Type | Default | Description |
---|---|---|---|
transform |
Matrix4 | The transform | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
fixedFrameTransform |
Transforms.LocalFrameToFixedFrame |
Transforms.eastNorthUpToFixedFrame
|
optional A 4x4 transformation matrix from a reference frame to the provided ellipsoid's fixed reference frame |
result |
HeadingPitchRoll | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new HeadingPitchRoll instance if none was provided.
static Cesium.Transforms.headingPitchRollQuaternion(origin, headingPitchRoll, ellipsoid, fixedFrameTransform, result) → Quaternion
Computes a quaternion from a reference frame with axes computed from the heading-pitch-roll angles
centered at the provided origin. Heading is the rotation from the local north
direction where a positive angle is increasing eastward. Pitch is the rotation from the local east-north plane. Positive pitch angles
are above the plane. Negative pitch angles are below the plane. Roll is the first rotation applied about the local east axis.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
headingPitchRoll |
HeadingPitchRoll | The heading, pitch, and roll. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
fixedFrameTransform |
Transforms.LocalFrameToFixedFrame |
Transforms.eastNorthUpToFixedFrame
|
optional A 4x4 transformation matrix from a reference frame to the provided ellipsoid's fixed reference frame |
result |
Quaternion | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Quaternion instance if none was provided.
Example:
// Get the quaternion from local heading-pitch-roll at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const heading = -Cesium.Math.PI_OVER_TWO;
const pitch = Cesium.Math.PI_OVER_FOUR;
const roll = 0.0;
const hpr = new HeadingPitchRoll(heading, pitch, roll);
const quaternion = Cesium.Transforms.headingPitchRollQuaternion(center, hpr);
static Cesium.Transforms.headingPitchRollToFixedFrame(origin, headingPitchRoll, ellipsoid, fixedFrameTransform, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame with axes computed from the heading-pitch-roll angles
centered at the provided origin to the provided ellipsoid's fixed reference frame. Heading is the rotation from the local north
direction where a positive angle is increasing eastward. Pitch is the rotation from the local east-north plane. Positive pitch angles
are above the plane. Negative pitch angles are below the plane. Roll is the first rotation applied about the local east axis.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
headingPitchRoll |
HeadingPitchRoll | The heading, pitch, and roll. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
fixedFrameTransform |
Transforms.LocalFrameToFixedFrame |
Transforms.eastNorthUpToFixedFrame
|
optional A 4x4 transformation matrix from a reference frame to the provided ellipsoid's fixed reference frame |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.
Example:
// Get the transform from local heading-pitch-roll at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const heading = -Cesium.Math.PI_OVER_TWO;
const pitch = Cesium.Math.PI_OVER_FOUR;
const roll = 0.0;
const hpr = new Cesium.HeadingPitchRoll(heading, pitch, roll);
const transform = Cesium.Transforms.headingPitchRollToFixedFrame(center, hpr);
static Cesium.Transforms.localFrameToFixedFrameGenerator(firstAxis, secondAxis) → Transforms.LocalFrameToFixedFrame
Generates a function that computes a 4x4 transformation matrix from a reference frame
centered at the provided origin to the provided ellipsoid's fixed reference frame.
Name | Type | Description |
---|---|---|
firstAxis |
String | name of the first axis of the local reference frame. Must be 'east', 'north', 'up', 'west', 'south' or 'down'. |
secondAxis |
String | name of the second axis of the local reference frame. Must be 'east', 'north', 'up', 'west', 'south' or 'down'. |
Returns:
The function that will computes a
4x4 transformation matrix from a reference frame, with first axis and second axis compliant with the parameters,
static Cesium.Transforms.northEastDownToFixedFrame(origin, ellipsoid, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame with an north-east-down axes
centered at the provided origin to the provided ellipsoid's fixed reference frame.
The local axes are defined as:
- The
x
axis points in the local north direction. - The
y
axis points in the local east direction. - The
z
axis points in the opposite direction of the ellipsoid surface normal which passes through the position.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.
Example:
// Get the transform from local north-east-down at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const transform = Cesium.Transforms.northEastDownToFixedFrame(center);
static Cesium.Transforms.northUpEastToFixedFrame(origin, ellipsoid, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame with an north-up-east axes
centered at the provided origin to the provided ellipsoid's fixed reference frame.
The local axes are defined as:
- The
x
axis points in the local north direction. - The
y
axis points in the direction of the ellipsoid surface normal which passes through the position. - The
z
axis points in the local east direction.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.
Example:
// Get the transform from local north-up-east at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const transform = Cesium.Transforms.northUpEastToFixedFrame(center);
static Cesium.Transforms.northWestUpToFixedFrame(origin, ellipsoid, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame with an north-west-up axes
centered at the provided origin to the provided ellipsoid's fixed reference frame.
The local axes are defined as:
- The
x
axis points in the local north direction. - The
y
axis points in the local west direction. - The
z
axis points in the direction of the ellipsoid surface normal which passes through the position.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.
Example:
// Get the transform from local north-West-Up at cartographic (0.0, 0.0) to Earth's fixed frame.
const center = Cesium.Cartesian3.fromDegrees(0.0, 0.0);
const transform = Cesium.Transforms.northWestUpToFixedFrame(center);
static Cesium.Transforms.pointToWindowCoordinates(modelViewProjectionMatrix, viewportTransformation, point, result) → Cartesian2
Transform a point from model coordinates to window coordinates.
Name | Type | Description |
---|---|---|
modelViewProjectionMatrix |
Matrix4 | The 4x4 model-view-projection matrix. |
viewportTransformation |
Matrix4 | The 4x4 viewport transformation. |
point |
Cartesian3 | The point to transform. |
result |
Cartesian2 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Cartesian2 instance if none was provided.
Preloads the data necessary to transform between the ICRF and Fixed axes, in either
direction, over a given interval. This function returns a promise that, when resolved,
indicates that the preload has completed.
Name | Type | Description |
---|---|---|
timeInterval |
TimeInterval | The interval to preload. |
Returns:
A promise that, when resolved, indicates that the preload has completed
and evaluation of the transformation between the fixed and ICRF axes will
no longer return undefined for a time inside the interval.
Example:
const interval = new Cesium.TimeInterval(...);
Promise.resolve(Cesium.Transforms.preloadIcrfFixed(interval)).then(function() {
// the data is now loaded
});
See:
static Cesium.Transforms.rotationMatrixFromPositionVelocity(position, velocity, ellipsoid, result) → Matrix3
Transform a position and velocity to a rotation matrix.
Name | Type | Default | Description |
---|---|---|---|
position |
Cartesian3 | The position to transform. | |
velocity |
Cartesian3 | The velocity vector to transform. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix3 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix3 instance if none was provided.
Type Definitions
Cesium.Transforms.LocalFrameToFixedFrame(origin, ellipsoid, result) → Matrix4
Computes a 4x4 transformation matrix from a reference frame
centered at the provided origin to the provided ellipsoid's fixed reference frame.
Name | Type | Default | Description |
---|---|---|---|
origin |
Cartesian3 | The center point of the local reference frame. | |
ellipsoid |
Ellipsoid |
Ellipsoid.WGS84
|
optional The ellipsoid whose fixed frame is used in the transformation. |
result |
Matrix4 | optional The object onto which to store the result. |
Returns:
The modified result parameter or a new Matrix4 instance if none was provided.