Matrix Class
The Matrix class holds a 3x3 matrix. This matrix is used mostly to set transform information for Bitmap or Canvas transformation.
Example:
var bitmap = Bitmap.fromFile("dat://moscrif.jpg");
var matrix = new Matrix();
//move bitmap to the midle of screen
matrix.setTranslate(System.width / 2 - bitmap.width / 2, System.height / 2 - bitmap.height / 2);
//rotate bitmap to 45°
matrix.preRotate(45);
//draw rotated bitmap
canvas.drawBitmapMatrix(bitmap, matrix);
Item Index
Methods
Properties
Methods
this
()
Object constructor creates new 3x3 matrix
postRotate
degreespxpy
Postconcats the matrix with the specified rotation. M' = R(degrees, px, py) * M.
Parameters:
Returns:
Example:
this._path = Path.fromSVG("M1....8.63z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setScale(2, 2, System.width / 2, System.height / 2);
// apply rotation
m.postRotate(-90, System.width / 3, System.height / 2); // rotate CCW
// apply transformation to the object
this._path.transform(m);
postScale
sxsy[px][py]
Postconcats the matrix with the specified scale. M' = S(sx, sy, px, py) * M.
Parameters:
Returns:
Example:
this._path = Path.fromSVG("M16...3z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setTranslate(0, -1*System.height / 4);
m.postScale(2, 2, System.width / 2, System.height / 4);
// apply transformation to the object
this._path.transform(m);
postSkew
kxky[px][py]
Postconcats the matrix with the specified skew. M' = K(kx, ky, px, py) * M.
Parameters:
Returns:
postTranslate
dxdy
Postconcats the matrix with the specified translation. M' = T(dx, dy) * M.
Returns:
Example:
this._path = Path.fromSVG("M1...3z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setScale(2, 2, System.width / 2, System.height / 2);
// apply movement
m.postTranslate(-1*System.width / 8, 0);
// apply transformation to the object
this._path.transform(m);
preRotate
degreespxpy
Preconcats the matrix with the specified rotation. M' = M * R(degrees, px, py).
Parameters:
Returns:
Example:
this._path = Path.fromSVG("M16.......63z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setScale(2, 2, System.width / 2, System.height / 2);
// apply rotation
m.preRotate(-90, System.width / 3, System.height / 2);
// apply transformation to the object
this._path.transform(m);
preScale
sxsy[px][py]
Preconcats the matrix with the specified scale. M' = M * S(sx, sy, px, py).
Parameters:
Returns:
Example:
this._path = Path.fromSVG("M16...3z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setTranslate(0, -1*System.height / 4);
m.preScale(2, 2, System.width / 2, System.height / 4);
// apply transformation to the object
this._path.transform(m);
preSkew
kxky[px][py]
Preconcats the matrix with the specified skew. M' = M * K(kx, ky, px, py).
Parameters:
Returns:
preTranslate
dxdy
Preconcats the matrix with the specified translation. M' = M * T(dx, dy).
Returns:
Example:
this._path = Path.fromSVG("M1...3z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// scale path
m.setScale(2, 2, System.width / 2, System.height / 2);
// apply movement
m.preTranslate(-1*System.width / 8, 0);
// apply transformation to the object
this._path.transform(m);
reset
()
Reset matrix to the matrix identity.
setRectToRect
srcleftsrctopsrcrightsrcbottomdstleftdsttopdstrightdstbottomscaleToFit
Set the matrix to the scale and translate values that map the source rectangle to the destination rectangle, returning true if the the result can be represented.
Parameters:
-
srcleftIntegerThe source rectangle to map from.
-
srctopIntegerThe source rectangle to map from.
-
srcrightIntegerThe source rectangle to map from.
-
srcbottomIntegerThe source rectangle to map from.
-
dstleftIntegerThe destination rectangle to map to.
-
dsttopIntegerThe destination rectangle to map to.
-
dstrightIntegerThe destination rectangle to map to.
-
dstbottomIntegerThe destination rectangle to map to.
-
scaleToFitSymbolThe source rectangle to map from.
- #fill - Scale in X and Y independently, so that src matches dst exactly. This may change the aspect ratio of the src.
- #start - Compute a scale that will maintain the original src aspect ratio, but will also ensure that src fits entirely inside dst. At least one axis (X or Y) will fit exactly. kStart aligns the result to the left and top edges of dst.
- #center - Compute a scale that will maintain the original src aspect ratio, but will also ensure that src fits entirely inside dst. At least one axis (X or Y) will fit exactly. The result is centered inside dst.
- #end - Compute a scale that will maintain the original src aspect ratio, but will also ensure that src fits entirely inside dst. At least one axis (X or Y) will fit exactly. kEnd aligns the result to the right and bottom edges of dst.
Returns:
Example:
this._path = Path.fromSVG("M16...63z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// map whole screen to the left bottom quarter of the screen
m.setRectToRect(0, 0, System.width, System.height,System.width / 2, System.height / 2, System.width, System.height, #fill);
// apply to the path object
this._path.transform(m);
setRotate
degreespxpy
Set the matrix to rotate around a pivot point at (px, py). The pivot point is the coordinate that should remain unchanged by the specified transformation.
Parameters:
Example:
this._path = Path.fromSVG("M16....128.63z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// enlarge pictures, keep coordinates of the center
m.setScale(4, 4, System.width / 2, System.height / 2);
// apply transformation to the path
this._path.transform(m);
setScale
sxsy[px][py]
Set the matrix to scale by sx and sy, with a pivot point at (px, py). The pivot point is the coordinate that should stay unchanged by the specified transformation.
Parameters:
Example:
this._path = Path.fromSVG("M16....128.63z");
// create transform matrix
var (l, t, r, b) = this._path.getBounds();
this._path.offset(-1*l, -1*t);
this._path.offset((System.width - (r - l)) / 2, (System.height - (b - t)) / 2);
var m = new Matrix();
// enlarge pictures, keep coordinates of the center
m.setScale(4, 4, System.width / 2, System.height / 2);
// apply transformation to the path
this._path.transform(m);
setSkew
kxky[px][py]
Set the matrix to skew by sx and sy, with a pivot point at (px, py). The pivot point is the coordinate that should remain unchanged by the specified transformation.
setTranslate
dxdy
Set the matrix to translate by (dx, dy).
Example:
// create transform matrix
var m = new Matrix();
// apply movement
m.setTranslate(320, 480);
// apply transformation to the path
this._path.transform(m);