- Qt 6.8
- Qt Quick
- QML Types
- matrix4x4
- Qt 6.8.3 Reference Documentation

# matrix4x4 QML Value Type

A matrix4x4 type is a 4-row and 4-column matrix. More...

## Detailed Description

A `matrix4x4` type has sixteen values, each accessible via the properties `m11` through `m44` in QML (in row/column order). Values of this type can be composed with the Qt.matrix4x4() function. Each attribute in a matrix4x4 is stored as a real (single-precision on ARM, double-precision on x86).

A property of type `matrix4x4` defaults to the identity matrix, whose diagonal entries `m11`, `m22`, `m33` and `m44` are all `1`, with all other components `0`.

The matrix4x4 type has the following idempotent functions which can be invoked in QML:

Function Signature | Description | Example
--- | --- | ---

translate(vector3d vector)

Multiplies `this` matrix4x4 by another that translates coordinates by the components of `vector`

     var m = Qt.matrix4x4();
     m.translate(Qt.vector3d(1,2,3));
     console.log(m.toString());
     // QMatrix4x4(1, 0, 0, 1, 0, 1, 0, 2, 0, 0, 1, 3, 0, 0, 0, 1)

rotate(real angle, vector3d axis)

Multiples `this` matrix4x4 by another that rotates coordinates through `angle` degrees about `axis`

     var m = Qt.matrix4x4();
     m.rotate(180,Qt.vector3d(1,0,0));
     console.log(m.toString());
     // QMatrix4x4(1, 0, 0, 0, 0, -1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1)

rotate(quaternion quaternion)

Multiples `this` matrix4x4 by another that rotates coordinates according to a specified `quaternion`. The `quaternion` is assumed to have been normalized.

     var m = Qt.matrix4x4();
     m.rotate(Qt.quaternion(0.5,0.5,0.5,-0.5));
     console.log(m.toString());
     // QMatrix4x4(0, 1, 0, 0, 0, 0, -1, 0, -1, 0, 0, 0, 0, 0, 0, 1)

scale(real factor)

Multiplies `this` matrix4x4 by another that scales coordinates by the given `factor`

     var m = Qt.matrix4x4();
     m.scale(2);
     console.log(m.toString());
     // QMatrix4x4(2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 2, 0, 0, 0, 0, 1)

scale(real x, real y, real z)

Multiplies `this` matrix4x4 by another that scales coordinates by the components `x`, `y`, and `z`

     var m = Qt.matrix4x4();
     m.scale(1,2,3);
     console.log(m.toString());
     // QMatrix4x4(1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 3, 0, 0, 0, 0, 1)

scale(vector3d vector)

Multiplies `this` matrix4x4 by another that scales coordinates by the components of `vector`

     var m = Qt.matrix4x4();
     m.scale(Qt.vector3d(1,2,3));
     console.log(m.toString());
     // QMatrix4x4(1, 0, 0, 0, 0, 2, 0, 0, 0, 0, 3, 0, 0, 0, 0, 1)

lookAt(vector3d eye, vector3d center, vector3d up)

Multiplies `this` matrix4x4 by a viewing matrix derived from an `eye` point. The `center` vector3d indicates the center of the view that the `eye` is looking at. The `up` vector3d indicates which direction should be considered up with respect to the `eye`.

     var m = Qt.matrix4x4();
     m.lookAt(Qt.vector3d(1,2,3),Qt.vector3d(1,2,0),Qt.vector3d(0,1,0));
     console.log(m.toString());
     // QMatrix4x4(1, 0, 0, -1, 0, 1, 0, -2, 0, 0, 1, -3, 0, 0, 0, 1)

matrix4x4 times(matrix4x4 other)

Returns the matrix4x4 result of multiplying `this` matrix4x4 with the `other` matrix4x4

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.matrix4x4(4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19);
     var c = a.times(b);
     console.log(c.toString());
     // QMatrix4x4(120, 130, 140, 150, 280, 306, 332, 358, 440, 482,
     //524, 566, 600, 658, 716, 774)

vector4d times(vector4d vector)

Returns the vector4d result of transforming the `vector` according to `this` matrix4x4 with the matrix applied pre-vector

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.vector4d(5,6,7,8);
     var c = a.times(b);
     console.log(c.toString()); // QVector4D(70, 174, 278, 382)

vector3d times(vector3d vector)

Returns the vector3d result of transforming the `vector` according to `this` matrix4x4 with the matrix applied pre-vector

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.vector3d(5,6,7);
     var c = a.times(b);
     console.log(c.toString()); // QVector3D(0.155556, 0.437037, 0.718518)

matrix4x4 times(real factor)

Returns the matrix4x4 result of multiplying `this` matrix4x4 with the scalar `factor`

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = 4.48;
     var c = a.times(b);
     console.log(c.toString());
     // QMatrix4x4(4.48, 8.96, 13.44, 17.92, 22.4, 26.88, 31.36, 35.84,
     // 40.32, 44.8, 49.28, 53.76, 58.24, 62.72, 67.2, 71.68)

matrix4x4 plus(matrix4x4 other)

Returns the matrix4x4 result of the addition of `this` matrix4x4 with the `other` matrix4x4

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.matrix4x4(5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20);
     var c = a.plus(b);
     console.log(c.toString());
     // QMatrix4x4(6, 8, 10, 12, 14, 16, 18, 20, 22,
     // 24, 26, 28, 30, 32, 34, 36)

matrix4x4 minus(matrix4x4 other)

Returns the matrix4x4 result of the subtraction of `other` matrix4x4 from `this` matrix4x4

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.matrix4x4(5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20);
     var c = a.minus(b);
     console.log(c.toString());
     // QMatrix4x4(-4, -4, -4, -4, -4, -4, -4, -4, -4,
     // -4, -4, -4, -4, -4, -4, -4)

vector4d row(int which)

Returns the vector4d row of `this` specified by `which`. Note: the `which` is 0-based access into the matrix.

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.vector4d(a.m21, a.m22, a.m23, a.m24);
     var c = a.row(2); // zero based access!  so not equal to b
     console.log(b.toString() + " " + c.toString());
     // QVector4D(5, 6, 7, 8) QVector4D(9, 10, 11, 12)

vector4d column(int which)

Returns the vector4d column of `this` specified by `which`. Note: the `which` is 0-based access into the matrix.

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.vector4d(a.m12, a.m22, a.m32, a.m42);
     var c = a.column(2); // zero based access!  so not equal to b
     console.log(b.toString() + " " + c.toString());
     // QVector4D(2, 6, 10, 14) QVector4D(3, 7, 11, 15)

real determinant()

Returns the determinant of `this` matrix4x4

     var a = Qt.matrix4x4(1,0,0,0,0,2,0,0,0,0,3,0,100,200,300,1);
     var b = a.determinant();
     console.log(b); // 6

matrix4x4 inverted()

Returns the inverse of `this` matrix4x4 if it exists, else the identity matrix.

     var a = Qt.matrix4x4(1,0,0,0,0,2,0,0,0,0,3,0,100,200,300,1);
     var b = a.inverted();
     console.log(b.toString());
     // QMatrix4x4(1, 0, 0, 0, 0, 0.5, 0, 0, 0, 0, 0.333333, 0, -100,
     // -100, -100, 1)

matrix4x4 transposed()

Returns the transpose of `this` matrix4x4

     var a = Qt.matrix4x4(1,0,0,0,0,2,0,0,0,0,3,0,100,200,300,1);
     var b = a.transposed();
     console.log(b.toString());
     // QMatrix4x4(1, 0, 0, 100, 0, 2, 0, 200, 0, 0, 3, 300, 0, 0, 0, 1)

rect mapRect(rect)

Maps the provided rectangle into the coordinate system defined by this matrix. If rotation or shearing has been specified, this function returns the bounding rectangle. This function was introduced in Qt 6.5.

     var a = Qt.matrix4x4(2,0,0,0,0,2,0,0,0,0,1,0,0,0,0,1);
     var b = a.mapRect(Qt.rect(10, 20, 30, 40));
     console.log(b.toString());
     // Qt.rect(20, 40, 60, 80)

point map(point)

Maps the provided point into the coordinate system defined by this matrix. This function was introduced in Qt 6.5.

     var a = Qt.matrix4x4(2,0,0,0,0,2,0,0,0,0,1,0,0,0,0,1);
     var b = a.map(10, 20);
     console.log(b.toString());
     // Qt.point(20, 40)

bool fuzzyEquals(matrix4x4 other, real epsilon)

Returns true if `this` matrix4x4 is approximately equal to the `other` matrix4x4. The approximation will be true if each attribute of `this` is within `epsilon` of the respective attribute of `other`. Note that `epsilon` is an optional argument, the default `epsilon` is 0.00001.

     var a = Qt.matrix4x4(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16);
     var b = Qt.matrix4x4(1.0001,2.0001,3.0002,4.0003,5.0001,6.0002,
                          7.0002,8.0004, 9.0001,10.0003,
                          11.0003,12.0004,13.0001,
                          14.0002,15.0003,16.0004);
     var c = a.fuzzyEquals(b);        // default epsilon
     var d = a.fuzzyEquals(b, 0.005); // supplied epsilon
     console.log(c + " " + d); // false true

This value type is provided by the QtQuick import.

See also QML Value Types.