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////////////////////////////////////////////////////////////////////////////////
//
// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements. See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License. You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
////////////////////////////////////////////////////////////////////////////////
package mx.utils
{
import flash.display.DisplayObject;
import flash.geom.Matrix;
import flash.geom.Matrix3D;
import flash.geom.PerspectiveProjection;
import flash.geom.Point;
import flash.geom.Rectangle;
import flash.geom.Utils3D;
import flash.geom.Vector3D;
import flash.system.ApplicationDomain;
import mx.core.mx_internal;
use namespace mx_internal;
[ExcludeClass]
/**
* @private
* The MatrixUtil class is for internal use only.
* Class for matrix and geometric related math routines.
*/
public final class MatrixUtil
{
include "../core/Version.as";
private static const RADIANS_PER_DEGREES:Number = Math.PI / 180;
mx_internal static var SOLUTION_TOLERANCE:Number = 0.1;
mx_internal static var MIN_MAX_TOLERANCE:Number = 0.1;
private static var staticPoint:Point = new Point();
// For use in getConcatenatedMatrix function
private static var fakeDollarParent:QName;
private static var uiComponentClass:Class;
private static var uiMovieClipClass:Class;
private static var usesMarshalling:Object;
private static var lastModuleFactory:Object;
private static var computedMatrixProperty:QName;
private static var $transformProperty:QName;
//--------------------------------------------------------------------------
//
// Class methods
//
//--------------------------------------------------------------------------
/**
* Returns rotation value clamped between -180 and 180 degreeds.
* This mimicks the Flash player behavior.
*/
public static function clampRotation(value:Number):Number
{
// Flash player doesn't handle values larger than 2^15 - 1 (FP-749).
if (value > 180 || value < -180)
{
value = value % 360;
if (value > 180)
value = value - 360;
else if (value < -180)
value = value + 360;
}
return value;
}
/**
* Returns a static Point object with the result.
* If matrix is null, point is untransformed.
*/
public static function transformPoint(x:Number, y:Number, m:Matrix):Point
{
if (!m)
{
staticPoint.x = x;
staticPoint.y = y;
return staticPoint;
}
staticPoint.x = m.a * x + m.c * y + m.tx;
staticPoint.y = m.b * x + m.d * y + m.ty;
return staticPoint;
}
public static function composeMatrix(x:Number = 0,
y:Number = 0,
scaleX:Number = 1,
scaleY:Number = 1,
rotation:Number = 0,
transformX:Number = 0,
transformY:Number = 0):Matrix
{
var m:Matrix = new Matrix();
m.translate(-transformX, -transformY);
m.scale(scaleX, scaleY);
if (rotation != 0)
m.rotate(rotation / 180 * Math.PI);
m.translate(transformX + x, transformY + y);
return m;
}
/**
* Decompose a matrix into its component scale, rotation, and translation parts.
* The Vector of Numbers passed in the components parameter will be
* populated by this function with the component parts.
*
* @param components Vector which holds the component scale, rotation
* and translation values.
* x = components[0]
* y = components[1]
* rotation = components[2]
* scaleX = components[3]
* scaleY = components[4]
*
* @param matrix The matrix to decompose
* @param transformX The x value of the transform center
* @param transformY The y value of the transform center
*/
public static function decomposeMatrix(components:Vector.<Number>,
matrix:Matrix,
transformX:Number = 0,
transformY:Number = 0):void
{
// else decompose matrix. Don't use MatrixDecompose(), it can return erronous values
// when negative scales (and therefore skews) are in use.
var Ux:Number;
var Uy:Number;
var Vx:Number;
var Vy:Number;
Ux = matrix.a;
Uy = matrix.b;
components[3] = Math.sqrt(Ux*Ux + Uy*Uy);
Vx = matrix.c;
Vy = matrix.d;
components[4] = Math.sqrt(Vx*Vx + Vy*Vy );
// sign of the matrix determinant will tell us if the space is inverted by a 180 degree skew or not.
var determinant:Number = Ux*Vy - Uy*Vx;
if (determinant < 0) // if so, choose y-axis scale as the skewed one. Unfortunately, its impossible to tell if it originally was the y or x axis that had the negative scale/skew.
{
components[4] = -(components[4]);
Vx = -Vx;
Vy = -Vy;
}
components[2] = Math.atan2( Uy, Ux ) / RADIANS_PER_DEGREES;
if (transformX != 0 || transformY != 0)
{
var postTransformCenter:Point = matrix.transformPoint(new Point(transformX,transformY));
components[0] = postTransformCenter.x - transformX;
components[1] = postTransformCenter.y - transformY;
}
else
{
components[0] = matrix.tx;
components[1] = matrix.ty;
}
}
/**
* @return Returns the union of <code>rect</code> and
* <code>Rectangle(left, top, right - left, bottom - top)</code>.
* Note that if rect is non-null, it will be updated to reflect the return value.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function rectUnion(left:Number, top:Number, right:Number, bottom:Number,
rect:Rectangle):Rectangle
{
if (!rect)
return new Rectangle(left, top, right - left, bottom - top);
var minX:Number = Math.min(rect.left, left);
var minY:Number = Math.min(rect.top, top);
var maxX:Number = Math.max(rect.right, right);
var maxY:Number = Math.max(rect.bottom, bottom);
rect.x = minX;
rect.y = minY;
rect.width = maxX - minX;
rect.height = maxY - minY;
return rect;
}
/**
* Calculates the bounding box of a post-transformed ellipse.
*
* @param cx The x coordinate of the ellipse's center
* @param cy The y coordinate of the ellipse's center
* @param rx The horizontal radius of the ellipse
* @param ry The vertical radius of the ellipse
* @param matrix The transformation matrix.
* @param rect If non-null, rect will be updated to the union of rect and
* the segment bounding box.
* @return Returns the union of the passed in rect with the
* bounding box of the the post-transformed ellipse.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function getEllipseBoundingBox(cx:Number, cy:Number,
rx:Number, ry:Number,
matrix:Matrix,
rect:Rectangle = null):Rectangle
{
var a:Number = matrix.a;
var b:Number = matrix.b;
var c:Number = matrix.c;
var d:Number = matrix.d;
// Ellipse can be represented by the following parametric equations:
//
// (1) x = cx + rx * cos(t)
// (2) y = cy + ry * sin(t)
//
// After applying transformation with matrix m(a, c, b, d) we get:
//
// (3) x = a * cx + a * cos(t) * rx + c * cy + c * sin(t) * ry + m.tx
// (4) y = b * cx + b * cos(t) * rx + d * cy + d * sin(t) * ry + m.ty
//
// In (3) and (4) x and y are functions of a parameter t. To find the extremums we need
// to find where dx/dt and dy/dt reach zero:
//
// (5) dx/dt = - a * sin(t) * rx + c * cos(t) * ry
// (6) dy/dt = - b * sin(t) * rx + d * cos(t) * ry
// (7) dx/dt = 0 <=> sin(t) / cos(t) = (c * ry) / (a * rx);
// (8) dy/dt = 0 <=> sin(t) / cos(t) = (d * ry) / (b * rx);
if (rx == 0 && ry == 0)
{
var pt:Point = new Point(cx, cy);
pt = matrix.transformPoint(pt);
return rectUnion(pt.x, pt.y, pt.x, pt.y, rect);
}
var t:Number;
var t1:Number;
if (a * rx == 0)
t = Math.PI / 2;
else
t = Math.atan((c * ry) / (a * rx));
if (b * rx == 0)
t1 = Math.PI / 2;
else
t1 = Math.atan((d * ry) / (b * rx));
var x1:Number = a * Math.cos(t) * rx + c * Math.sin(t) * ry;
var x2:Number = -x1;
x1 += a * cx + c * cy + matrix.tx;
x2 += a * cx + c * cy + matrix.tx;
var y1:Number = b * Math.cos(t1) * rx + d * Math.sin(t1) * ry;
var y2:Number = -y1;
y1 += b * cx + d * cy + matrix.ty;
y2 += b * cx + d * cy + matrix.ty;
return rectUnion(Math.min(x1, x2), Math.min(y1, y2), Math.max(x1, x2), Math.max(y1, y2), rect);
}
/**
* @param x0 x coordinate of the first control point
* @param y0 y coordinate of the first control point
* @param x1 x coordinate of the second control point
* @param y1 y coordinate of the second control point
* @param x2 x coordinate of the third control point
* @param y2 y coordinate of the third control point
* @param sx The pre-transform scale factor for x coordinates.
* @param sy The pre-transform scale factor for y coordinates.
* @param matrix The transformation matrix. Can be null for identity transformation.
* @param rect If non-null, rect will be updated to the union of rect and
* the segment bounding box.
* @return Returns the union of the post-transformed quadratic
* bezier segment's axis aligned bounding box and the passed in rect.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static public function getQBezierSegmentBBox(x0:Number, y0:Number,
x1:Number, y1:Number,
x2:Number, y2:Number,
sx:Number, sy:Number,
matrix:Matrix,
rect:Rectangle):Rectangle
{
var pt:Point;
pt = MatrixUtil.transformPoint(x0 * sx, y0 * sy, matrix);
x0 = pt.x;
y0 = pt.y;
pt = MatrixUtil.transformPoint(x1 * sx, y1 * sy, matrix);
x1 = pt.x;
y1 = pt.y;
pt = MatrixUtil.transformPoint(x2 * sx, y2 * sy, matrix);
x2 = pt.x;
y2 = pt.y;
var minX:Number = Math.min(x0, x2);
var maxX:Number = Math.max(x0, x2);
var minY:Number = Math.min(y0, y2);
var maxY:Number = Math.max(y0, y2);
var txDiv:Number = x0 - 2 * x1 + x2;
if (txDiv != 0)
{
var tx:Number = (x0 - x1) / txDiv;
if (0 <= tx && tx <= 1)
{
var x:Number = (1 - tx) * (1 - tx) * x0 + 2 * tx * (1 - tx) * x1 + tx * tx * x2;
minX = Math.min(x, minX);
maxX = Math.max(x, maxX);
}
}
var tyDiv:Number = y0 - 2 * y1 + y2;
if (tyDiv != 0)
{
var ty:Number = (y0 - y1) / tyDiv;
if (0 <= ty && ty <= 1)
{
var y:Number = (1 - ty) * (1 - ty) * y0 + 2 * ty * (1 - ty) * y1 + ty * ty * y2;
minY = Math.min(y, minY);
maxY = Math.max(y, maxY);
}
}
return rectUnion(minX, minY, maxX, maxY, rect);
}
/**
* @param width The width of the bounds to be transformed.
* @param height The height of the bounds to be transformed.
* @param matrix The transfomration matrix.
*
* @param vec If vec is non-null it will be set to the vector from the
* transformed bounds top left to the untransformed bounds top left
* in the coordinate space defined by <code>matrix</code>.
* This is useful if you want to align the transformed bounds to x,y
* by modifying the object's position. Moving the object by
* <code>x + vec.x</code> and <code>y + vec.y</code> respectively
* will offset the transformed bounds top left corner by x,y.
*
* @return Returns the transformed bounds. Note that the Point object returned will be reused
* by other MatrixUtil methods.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function transformSize(width:Number, height:Number, matrix:Matrix):Point
{
const a:Number = matrix.a;
const b:Number = matrix.b;
const c:Number = matrix.c;
const d:Number = matrix.d;
// transform point (0,0)
var x1:Number = 0;
var y1:Number = 0;
// transform point (width, 0)
var x2:Number = width * a;
var y2:Number = width * b;
// transform point (0, height)
var x3:Number = height * c;
var y3:Number = height * d;
// transform point (width, height)
var x4:Number = x2 + x3;
var y4:Number = y2 + y3;
var minX:Number = Math.min(Math.min(x1, x2), Math.min(x3, x4));
var maxX:Number = Math.max(Math.max(x1, x2), Math.max(x3, x4));
var minY:Number = Math.min(Math.min(y1, y2), Math.min(y3, y4));
var maxY:Number = Math.max(Math.max(y1, y2), Math.max(y3, y4));
staticPoint.x = maxX - minX;
staticPoint.y = maxY - minY;
return staticPoint;
}
/**
* @param width The width of the bounds to be transformed.
* @param height The height of the bounds to be transformed.
* @param matrix The transfomration matrix.
*
* @param topleft If topLeft is non-null it will be used as the origin of the bounds
* rectangle to be transformed. On return, it will be set to the top left of the rectangle
* after transformation.
*
* @return Returns the transformed width and height. Note that the Point object returned will be reused
* by other MatrixUtil methods.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function transformBounds(width:Number, height:Number, matrix:Matrix, topLeft:Point = null):Point
{
const a:Number = matrix.a;
const b:Number = matrix.b;
const c:Number = matrix.c;
const d:Number = matrix.d;
// transform point (0,0)
var x1:Number = 0;
var y1:Number = 0;
// transform point (width, 0)
var x2:Number = width * a;
var y2:Number = width * b;
// transform point (0, height)
var x3:Number = height * c;
var y3:Number = height * d;
// transform point (width, height)
var x4:Number = x2 + x3;
var y4:Number = y2 + y3;
var minX:Number = Math.min(Math.min(x1, x2), Math.min(x3, x4));
var maxX:Number = Math.max(Math.max(x1, x2), Math.max(x3, x4));
var minY:Number = Math.min(Math.min(y1, y2), Math.min(y3, y4));
var maxY:Number = Math.max(Math.max(y1, y2), Math.max(y3, y4));
staticPoint.x = maxX - minX;
staticPoint.y = maxY - minY;
if (topLeft)
{
const tx:Number = matrix.tx;
const ty:Number = matrix.ty;
const x:Number = topLeft.x;
const y:Number = topLeft.y;
topLeft.x = minX + a * x + b * y + tx;
topLeft.y = minY + c * x + d * y + ty;
}
return staticPoint;
}
/**
* Returns the axis aligned bounding box <code>bounds</code> transformed
* with <code>matrix</code> and then projected with <code>projection</code>.
*
* @param bounds The bounds, in child coordinates, to be transformed and projected.
* @param matrix <p>The transformation matrix. Note that the method will clobber the
* original matrix values.</p>
* @param projection The projection.
* @return Returns the <code>bounds</code> parameter that has been updated with the
* transformed and projected bounds.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function projectBounds(bounds:Rectangle,
matrix:Matrix3D,
projection:PerspectiveProjection):Rectangle
{
// Setup the matrix
var centerX:Number = projection.projectionCenter.x;
var centerY:Number = projection.projectionCenter.y;
matrix.appendTranslation(-centerX, -centerY, projection.focalLength);
matrix.append(projection.toMatrix3D());
// Project the corner points
var pt1:Vector3D = new Vector3D(bounds.left, bounds.top, 0);
var pt2:Vector3D = new Vector3D(bounds.right, bounds.top, 0)
var pt3:Vector3D = new Vector3D(bounds.left, bounds.bottom, 0);
var pt4:Vector3D = new Vector3D(bounds.right, bounds.bottom, 0);
pt1 = Utils3D.projectVector(matrix, pt1);
pt2 = Utils3D.projectVector(matrix, pt2);
pt3 = Utils3D.projectVector(matrix, pt3);
pt4 = Utils3D.projectVector(matrix, pt4);
// Find the bounding box in 2D
var maxX:Number = Math.max(Math.max(pt1.x, pt2.x), Math.max(pt3.x, pt4.x));
var minX:Number = Math.min(Math.min(pt1.x, pt2.x), Math.min(pt3.x, pt4.x));
var maxY:Number = Math.max(Math.max(pt1.y, pt2.y), Math.max(pt3.y, pt4.y));
var minY:Number = Math.min(Math.min(pt1.y, pt2.y), Math.min(pt3.y, pt4.y));
// Add back the projection center
bounds.x = minX + centerX;
bounds.y = minY + centerY;
bounds.width = maxX - minX;
bounds.height = maxY - minY;
return bounds;
}
/**
* @param matrix
* @return Returns true when <code>pt == matrix.DeltaTransformPoint(pt)</code>
* for any <code>pt:Point</code> (<code>matrix</code> is identity matrix,
* when disregarding the translation part).
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function isDeltaIdentity(matrix:Matrix):Boolean
{
return (matrix.a == 1 && matrix.d == 1 &&
matrix.b == 0 && matrix.c == 0);
}
/**
* <code>fitBounds</code> Calculates a size (x,y) for a bounding box (0,0,x,y)
* such that the bounding box transformed with <code>matrix</code> will fit
* into (0,0,width,height).
*
* @param width This is the width of the bounding box that calculated size
* needs to fit in.
*
* @param height This is the height of the bounding box that the calculated
* size needs to fit in.
*
* @param matrix This defines the transformations that the function will take
* into account when calculating the size. The bounding box (0,0,x,y) of the
* calculated size (x,y) transformed with <code>matrix</code> will fit in the
* specified <code>width</code> and <code>height</code>.
*
* @param explicitWidth Explicit width for the calculated size. The function
* will first try to find a solution using this width.
*
* @param explicitHeight Preferred height for the calculated size. The function
* will first try to find a solution using this height.
*
* @param preferredWidth Preferred width for the calculated size. If possible
* the function will set the calculated size width to this value.
*
* @param preferredHeight Preferred height for the calculated size. If possible
* the function will set the calculated size height to this value.
*
* @param minWidth The minimum allowed value for the calculated size width.
*
* @param minHeight The minimum allowed value for the calculated size height.
*
* @param maxWidth The maximum allowed value for the calculated size width.
*
* @param maxHeight The maximum allowed value for the calculated size height.
*
* @return Returns the size (x,y) such that the bounding box (0,0,x,y) will
* fit into (0,0,width,height) after transformation with <code>matrix</code>.
* Returns null if there is no possible solution.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function fitBounds(width:Number, height:Number, matrix:Matrix,
explicitWidth:Number, explicitHeight:Number,
preferredWidth:Number, preferredHeight:Number,
minWidth:Number, minHeight:Number,
maxWidth:Number, maxHeight:Number):Point
{
if (isNaN(width) && isNaN(height))
return new Point(preferredWidth, preferredHeight);
// Allow for precision errors by including tolerance for certain values.
const newMinWidth:Number = (minWidth < MIN_MAX_TOLERANCE) ? 0 : minWidth - MIN_MAX_TOLERANCE;
const newMinHeight:Number = (minHeight < MIN_MAX_TOLERANCE) ? 0 : minHeight - MIN_MAX_TOLERANCE;
const newMaxWidth:Number = maxWidth + MIN_MAX_TOLERANCE;
const newMaxHeight:Number = maxHeight + MIN_MAX_TOLERANCE;
var actualSize:Point;
if (!isNaN(width) && !isNaN(height))
{
actualSize = calcUBoundsToFitTBounds(width, height, matrix,
newMinWidth, newMinHeight,
newMaxWidth, newMaxHeight);
// If we couldn't fit in both dimensions, try to fit only one and
// don't stick out of the other
if (!actualSize)
{
var actualSize1:Point;
actualSize1 = fitTBoundsWidth(width, matrix,
explicitWidth, explicitHeight,
preferredWidth, preferredHeight,
newMinWidth, newMinHeight,
newMaxWidth, newMaxHeight);
// If we fit the width, but not the height.
if (actualSize1)
{
var fitHeight:Number = transformSize(actualSize1.x, actualSize1.y, matrix).y;
if (fitHeight - SOLUTION_TOLERANCE > height)
actualSize1 = null;
}
var actualSize2:Point
actualSize2 = fitTBoundsHeight(height, matrix,
explicitWidth, explicitHeight,
preferredWidth, preferredHeight,
newMinWidth, newMinHeight,
newMaxWidth, newMaxHeight);
// If we fit the height, but not the width
if (actualSize2)
{
var fitWidth:Number = transformSize(actualSize2.x, actualSize2.y, matrix).x;
if (fitWidth - SOLUTION_TOLERANCE > width)
actualSize2 = null;
}
if (actualSize1 && actualSize2)
{
// Pick a solution
actualSize = ((actualSize1.x * actualSize1.y) > (actualSize2.x * actualSize2.y)) ? actualSize1 : actualSize2;
}
else if (actualSize1)
{
actualSize = actualSize1;
}
else
{
actualSize = actualSize2;
}
}
return actualSize;
}
else if (!isNaN(width))
{
return fitTBoundsWidth(width, matrix,
explicitWidth, explicitHeight,
preferredWidth, preferredHeight,
newMinWidth, newMinHeight,
newMaxWidth, newMaxHeight);
}
else
{
return fitTBoundsHeight(height, matrix,
explicitWidth, explicitHeight,
preferredWidth, preferredHeight,
newMinWidth, newMinHeight,
newMaxWidth, newMaxHeight);
}
}
/**
* @private
*
* <code>fitTBoundsWidth</code> Calculates a size (x,y) for a bounding box (0,0,x,y)
* such that the bounding box transformed with <code>matrix</code> will fit
* into the specified width.
*
* @param width This is the width of the bounding box that calculated size
* needs to fit in.
*
* @param matrix This defines the transformations that the function will take
* into account when calculating the size. The bounding box (0,0,x,y) of the
* calculated size (x,y) transformed with <code>matrix</code> will fit in the
* specified <code>width</code> and <code>height</code>.
*
* @param explicitWidth Explicit width for the calculated size. The function
* will first try to find a solution using this width.
*
* @param explicitHeight Preferred height for the calculated size. The function
* will first try to find a solution using this height.
*
* @param preferredWidth Preferred width for the calculated size. If possible
* the function will set the calculated size width to this value.
*
* @param preferredHeight Preferred height for the calculated size. If possible
* the function will set the calculated size height to this value.
*
* @param minWidth The minimum allowed value for the calculated size width.
*
* @param minHeight The minimum allowed value for the calculated size height.
*
* @param maxWidth The maximum allowed value for the calculated size width.
*
* @param maxHeight The maximum allowed value for the calculated size height.
*
* @return Returns the size (x,y) such that the bounding box (0,0,x,y) will
* fit into (0,0,width,height) after transformation with <code>matrix</code>.
* Returns null if there is no possible solution.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
private static function fitTBoundsWidth(width:Number, matrix:Matrix,
explicitWidth:Number, explicitHeight:Number,
preferredWidth:Number, preferredHeight:Number,
minWidth:Number, minHeight:Number,
maxWidth:Number, maxHeight:Number):Point
{
var actualSize:Point;
// cases 1 and 2: only explicit width or explicit height is specified,
// so we try to find a solution with that hard constraint.
if (!isNaN(explicitWidth) && isNaN(explicitHeight))
{
actualSize = calcUBoundsToFitTBoundsWidth(width, matrix,
explicitWidth, preferredHeight,
explicitWidth, minHeight,
explicitWidth, maxHeight);
if (actualSize)
return actualSize;
}
else if (isNaN(explicitWidth) && !isNaN(explicitHeight))
{
actualSize = calcUBoundsToFitTBoundsWidth(width, matrix,
preferredWidth, explicitHeight,
minWidth, explicitHeight,
maxWidth, explicitHeight);
if (actualSize)
return actualSize;
}
// case 3: default case. When explicitWidth, explicitHeight are both set
// or not set, we use the preferred size since calcUBoundsToFitTBoundsWidth
// will just pick one.
actualSize = calcUBoundsToFitTBoundsWidth(width, matrix,
preferredWidth, preferredHeight,
minWidth, minHeight,
maxWidth, maxHeight);
return actualSize;
}
/**
* @private
*
* <code>fitTBoundsWidth</code> Calculates a size (x,y) for a bounding box (0,0,x,y)
* such that the bounding box transformed with <code>matrix</code> will fit
* into the specified height.
*
* @param height This is the height of the bounding box that the calculated
* size needs to fit in.
*
* @param matrix This defines the transformations that the function will take
* into account when calculating the size. The bounding box (0,0,x,y) of the
* calculated size (x,y) transformed with <code>matrix</code> will fit in the
* specified <code>width</code> and <code>height</code>.
*
* @param explicitWidth Explicit width for the calculated size. The function
* will first try to find a solution using this width.
*
* @param explicitHeight Preferred height for the calculated size. The function
* will first try to find a solution using this height.
*
* @param preferredWidth Preferred width for the calculated size. If possible
* the function will set the calculated size width to this value.
*
* @param preferredHeight Preferred height for the calculated size. If possible
* the function will set the calculated size height to this value.
*
* @param minWidth The minimum allowed value for the calculated size width.
*
* @param minHeight The minimum allowed value for the calculated size height.
*
* @param maxWidth The maximum allowed value for the calculated size width.
*
* @param maxHeight The maximum allowed value for the calculated size height.
*
* @return Returns the size (x,y) such that the bounding box (0,0,x,y) will
* fit into (0,0,width,height) after transformation with <code>matrix</code>.
* Returns null if there is no possible solution.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
private static function fitTBoundsHeight(height:Number, matrix:Matrix,
explicitWidth:Number, explicitHeight:Number,
preferredWidth:Number, preferredHeight:Number,
minWidth:Number, minHeight:Number,
maxWidth:Number, maxHeight:Number):Point
{
var actualSize:Point;
// cases 1 and 2: only explicit width or explicit height is specified,
// so we try to find a solution with that hard constraint.
if (!isNaN(explicitWidth) && isNaN(explicitHeight))
{
actualSize = calcUBoundsToFitTBoundsHeight(height, matrix,
explicitWidth, preferredHeight,
explicitWidth, minHeight,
explicitWidth, maxHeight);
if (actualSize)
return actualSize;
}
else if (isNaN(explicitWidth) && !isNaN(explicitHeight))
{
actualSize = calcUBoundsToFitTBoundsHeight(height, matrix,
preferredWidth, explicitHeight,
minWidth, explicitHeight,
maxWidth, explicitHeight);
if (actualSize)
return actualSize;
}
// case 3: default case. When explicitWidth, explicitHeight are both set
// or not set, we use the preferred size since calcUBoundsToFitTBoundsWidth
// will just pick one.
actualSize = calcUBoundsToFitTBoundsHeight(height, matrix,
preferredWidth, preferredHeight,
minWidth, minHeight,
maxWidth, maxHeight);
return actualSize;
}
/**
* Calculates (x,y) such that the bounding box (0,0,x,y) transformed
* with <code>matrix</code> will have bounding box with
* height equal to <code>h</code>.
* x and y are restricted by <code>minX</code>, <code>maxX</code> and
* <code>minY</code>, <code>maxY</code>.
*
* If possible x will be set to <code>preferredX</code> or
* y will be set to <code>preferredY</code>.
*
* When there are multiple solutions, the function picks the one that
* minimizes the bounding box area of transformed (0,0,x,y).
*
* The functon assumes <code>minX >= 0</code> and <code>minY >= 0</code>
* (solution components x and y are non-negative).
*
* @return Returns Point(x,y) or null if no solution exists.
*
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static public function calcUBoundsToFitTBoundsHeight(h:Number,
matrix:Matrix,
preferredX:Number,
preferredY:Number,
minX:Number,
minY:Number,
maxX:Number,
maxY:Number):Point
{
// Untransformed bounds size is (x,y). The corners of the untransformed
// bounding box are p1(0,0) p2(x,0) p3(0,y) p4(x,y).
// Matrix is | a c tx |
// | b d ty |
//
// After transfomation with the matrix those four points are:
// t1 = (0, 0) = matrix.deltaTransformPoint(p1)
// t2 = (ax, bx) = matrix.deltaTransformPoint(p2)
// t3 = (cy, dy) = matrix.deltaTransformPoint(p3)
// t4 = (ax + cy, cx + dy) = matrix.deltaTransformPoint(p4)
//
// The transformed bounds bounding box dimensions are (w,h):
// (1) w = max( t1.x, t2.x, t3.x, t4.x ) - min( t1.x, t2.x, t3.x, t4.x)
// (2) h = max( t1.y, t2.y, t3.y, t4.y ) - min( t1.y, t2.y, t3.y, t4.y)
//
// Looking at all the possible cases for min and max functions above,
// we can construct and solve simple linear systems for x and y.
// For example in the case of
// t1.x <= t2.x <= t3.x <= t4.x
// our first equation is
// (1) w = t4.x - t1.x <==> w = ax + cy
//
// To minimize the cases we're looking at we can take advantage of
// the limits we have: x >= 0, y >= 0;
// Taking into account these limits we deduce that:
// a*c >= 0 gives us (1) w = abs( t4.x - t1.x ) = abs( ax + cy )
// a*c < 0 gives us (1) w = abs( t2.x - t3.x ) = abs( ax - cy )
// b*d >= 0 gives us (2) h = abs( t4.y - t1.y ) = abs( bx + dy )
// b*d < 0 gives us (2) h = abs( t2.y - t3.y ) = abs( bx - dy )
//
// If we do a substitution such that
// c1 = a*c >= 0 ? c : -c
// d1 = b*d >= 0 ? d : -d
// we get the following linear system:
// (1) w = abs( ax + c1y )
// (2) h = abs( bx + d1y )
//
// Since we're matching height we only care about (2)
var b:Number = matrix.b;
var d:Number = matrix.d;
// If components are very close to zero, zero them out to handle the special cases
if (-1.0e-9 < b && b < +1.0e-9)
b = 0;
if (-1.0e-9 < d && d < +1.0e-9)
d = 0;
if (b == 0 && d == 0)
return null; // No solution
// Handle special cases first
if (b == 0 && d == 0)
return null; // No solution
if (b == 0)
return new Point( preferredX, h / Math.abs(d) );
else if (d == 0)
return new Point( h / Math.abs(b), preferredY );
const d1:Number = (b*d >= 0) ? d : -d;
// Now we have the following linear sytesm:
// (1) x = preferredX or y = preferredY
// (2) h = abs( bx + d1y )
var s:Point;
var x:Number;
var y:Number;
if (d1 != 0 && preferredX > 0)
{
const invD1:Number = 1 / d1;
preferredX = Math.max(minX, Math.min(maxX, preferredX));
x = preferredX;
// Case1:
// bx + d1y >= 0
// x = preferredX
y = (h - b * x) * invD1;
if (minY <= y && y <= maxY &&
b * x + d1 * y >= 0 ) // Satisfy Case1
{
s = new Point(x, y);
}
// Case2:
// bx + d1y < 0
// x = preferredX
y = (-h - b * x) * invD1;
if (minY <= y && y <= maxY &&
b * x + d1 * y < 0 ) // Satisfy Case2
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).x > transformSize(x, y, matrix).x)
s = new Point(x, y);
}
}
if (b != 0 && preferredY > 0)
{
const invB:Number = 1 / b;
preferredY = Math.max(minY, Math.min(maxY, preferredY));
y = preferredY;
// Case3:
// bx + d1y >= 0
// y = preferredY
x = ( h - d1 * y ) * invB;
if (minX <= x && x <= maxX &&
b * x + d1 * y >= 0) // Satisfy Case3
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).x > transformSize(x, y, matrix).x)
s = new Point(x, y);
}
// Case4:
// bx + d1y < 0
// y = preferredY
x = ( -h - d1 * y ) * invB;
if (minX <= x && x <= maxX &&
b * x + d1 * y < 0) // Satisfy Case4
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).x > transformSize(x, y, matrix).x)
s = new Point(x, y);
}
}
// If there's already a solution that matches preferred dimention, return
if (s)
return s;
// Find a solution that matches the width and minimizes the height:
const a:Number = matrix.a;
const c:Number = matrix.c;
const c1:Number = ( a*c >= 0 ) ? c : -c;
return solveEquation(b, d1, h, minX, minY, maxX, maxY, a, c1);
}
/**
* Calculates (x,y) such that the bounding box (0,0,x,y) transformed
* with <code>matrix</code> will have bounding box with
* width equal to <code>w</code>.
* x and y are restricted by <code>minX</code>, <code>maxX</code> and
* <code>minY</code>, <code>maxY</code>.
*
* If possible x will be set to <code>preferredX</code> or
* y will be set to <code>preferredY</code>.
*
* When there are multiple solutions, the function picks the one that
* minimizes the bounding box area of transformed (0,0,x,y).
*
* The functon assumes <code>minX >= 0</code> and <code>minY >= 0</code>
* (solution components x and y are non-negative).
*
* @return Returns Point(x,y) or null if no solution exists.
*
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static public function calcUBoundsToFitTBoundsWidth(w:Number,
matrix:Matrix,
preferredX:Number,
preferredY:Number,
minX:Number,
minY:Number,
maxX:Number,
maxY:Number):Point
{
// Untransformed bounds size is (x,y). The corners of the untransformed
// bounding box are p1(0,0) p2(x,0) p3(0,y) p4(x,y).
// Matrix is | a c tx |
// | b d ty |
//
// After transfomation with the matrix those four points are:
// t1 = (0, 0) = matrix.deltaTransformPoint(p1)
// t2 = (ax, bx) = matrix.deltaTransformPoint(p2)
// t3 = (cy, dy) = matrix.deltaTransformPoint(p3)
// t4 = (ax + cy, cx + dy) = matrix.deltaTransformPoint(p4)
//
// The transformed bounds bounding box dimensions are (w,h):
// (1) w = max( t1.x, t2.x, t3.x, t4.x ) - min( t1.x, t2.x, t3.x, t4.x)
// (2) h = max( t1.y, t2.y, t3.y, t4.y ) - min( t1.y, t2.y, t3.y, t4.y)
//
// Looking at all the possible cases for min and max functions above,
// we can construct and solve simple linear systems for x and y.
// For example in the case of
// t1.x <= t2.x <= t3.x <= t4.x
// our first equation is
// (1) w = t4.x - t1.x <==> w = ax + cy
//
// To minimize the cases we're looking at we can take advantage of
// the limits we have: x >= 0, y >= 0;
// Taking into account these limits we deduce that:
// a*c >= 0 gives us (1) w = abs( t4.x - t1.x ) = abs( ax + cy )
// a*c < 0 gives us (1) w = abs( t2.x - t3.x ) = abs( ax - cy )
// b*d >= 0 gives us (2) h = abs( t4.y - t1.y ) = abs( bx + dy )
// b*d < 0 gives us (2) h = abs( t2.y - t3.y ) = abs( bx - dy )
//
// If we do a substitution such that
// c1 = a*c >= 0 ? c : -c
// d1 = b*d >= 0 ? d : -d
// we get the following linear system:
// (1) w = abs( ax + c1y )
// (2) h = abs( bx + d1y )
//
// Since we're matching width we only care about (1)
var a:Number = matrix.a;
var c:Number = matrix.c;
// If components are very close to zero, zero them out to handle the special cases
if (-1.0e-9 < a && a < +1.0e-9)
a = 0;
if (-1.0e-9 < c && c < +1.0e-9)
c = 0;
// Handle special cases first
if (a == 0 && c == 0)
return null; // No solution
if (a == 0)
return new Point( preferredX, w / Math.abs(c) );
else if (c == 0)
return new Point( w / Math.abs(a), preferredY );
const c1:Number = ( a*c >= 0 ) ? c : -c;
// Now we have the following linear sytesm:
// (1) w = abs( ax + c1y )
// (2) x = preferredX or y = preferredY
var s:Point;
var x:Number;
var y:Number;
if (c1 != 0 && preferredX > 0)
{
const invC1:Number = 1 / c1;
preferredX = Math.max(minX, Math.min(maxX, preferredX));
x = preferredX;
// Case1:
// a * x + c1 * y >= 0
// x = preferredX
y = (w - a * x) * invC1;
if (minY <= y && y <= maxY &&
a * x + c1 * y >= 0 ) // Satisfy Case1
{
s = new Point(x, y);
}
// Case2:
// a * x + c1 * y < 0
// x = preferredX
y = (-w - a * x) * invC1;
if (minY <= y && y <= maxY &&
a * x + c1 * y < 0 ) // Satisfy Case2
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).y > transformSize(x, y, matrix).y)
s = new Point(x, y);
}
}
if (a != 0 && preferredY > 0)
{
const invA:Number = 1 / a;
preferredY = Math.max(minY, Math.min(maxY, preferredY));
y = preferredY;
// Case3:
// a * x + c1 * y >= 0
// y = preferredY
x = (w - c1 * y ) * invA;
if (minX <= x && x <= maxX &&
a * x + c1 * y >= 0) // Satisfy Case3
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).y > transformSize(x, y, matrix).y)
s = new Point(x, y);
}
// Case4:
// a * x + c1 * y < 0
// y = preferredY
x = (-w - c1 * y ) * invA;
if (minX <= x && x <= maxX &&
a * x + c1 * y < 0) // Satisfy Case4
{
// If there is no solution, or the new solution yields smaller value, pick the new solution.
if (!s || transformSize(s.x, s.y, matrix).y > transformSize(x, y, matrix).y)
s = new Point(x, y);
}
}
// If there's already a solution that matches preferred dimention, return
if (s)
return s;
// Find a solution that matches the width and minimizes the height:
const b:Number = matrix.b;
const d:Number = matrix.d;
const d1:Number = (b*d >= 0) ? d : -d;
return solveEquation(a, c1, w, minX, minY, maxX, maxY, b, d1);
}
/**
* Finds a solution (x,y) for the equation abs(a*x + c*y) = w such that
* abs(b*x +d*y) is minimized.
* If there is infinite number of solutions, x and y are picked to be
* as close as possible.
*
* Doesn't handle cases where <code>a</code> or <code>c</code> are zero.
*
* @return Returns Point(x,y)
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static private function solveEquation(a:Number,
c:Number,
w:Number,
minX:Number,
minY:Number,
maxX:Number,
maxY:Number,
b:Number,
d:Number):Point
{
if (a == 0 || c == 0)
return null; // x and y are not co-dependent
// (1) w = abs( ax + cy )
// Find the range of solutsion for y and pick:
var x:Number;
var y:Number;
var s:Point;
// Case1: ax + cy >= 0, from (1) above we get:
// (1) x = (w - cy) / a
//
// Lets find the possible range of values for y:
// We know that
// (3) minX <= x <= maxX
//
// Substitute x with (w - cy)/a in (3):
// (3) minX - w/a <= -cy/a <= maxX - w/a
// (3) min( A, B ) <= y <= max( A, B ), where
// A = (minX - w/a) * (-a/c)
// B = (maxX - w/a) * (-a/c)
var A:Number = (w - minX * a) / c;
var B:Number = (w - maxX * a) / c;
var rangeMinY:Number = Math.max(minY, Math.min(A, B));
var rangeMaxY:Number = Math.min(maxY, Math.max(A, B));
const det:Number = (b * c - a * d);
// We have a possible solution for Case1 if the range for y is valid
if (rangeMinY <= rangeMaxY)
{
// Now that we have a valid range for y, we need to pick a value within
// that range.
//
// We calculate the value based on a custom condition.
//
// The custom condition that we use could be anything that defines
// another equation for x and y. Some examples are:
// "make x and y as close as possible": y = w / ( a + c );
// "minimize abs(bx + dy)": y = b * w / det
// "preserve aspect ratio": y = w / ( a * preferredX / preferredY + c );
if (Math.abs(det) < 1.0e-9)
{
// There is infinite number of solutions, lets pick x == y
y = w / ( a + c );
}
else
{
// Minimize abs(bx + dy) - we need to solve:
// abs( b * ( w - c * y ) / a + d * y ) = 0
// which gives us:
y = b * w / det;
}
// Now that we have the y value calculated from the custom condition,
// we clamp with the range. This gives us a solution with
// values as close as possible to satisfy our custom condition when
// the condition is a linear function of x and y (in our case it is).
y = Math.max(rangeMinY, Math.min(y, rangeMaxY));
x = (w - c * y) / a;
return new Point(x, y);
}
// Case2: ax + cy < 0, from (1) above we get:
// (1) x = (-w - cy) / a
//
// Lets find the possible range of values for y:
// We know that
// (3) minX <= x <= maxX
//
// Substitute x with (-w - cy)/a in (3):
// (3) minX + w/a <= -cy/a <= maxX + w/a
// (3) min( A, B ) <= y <= max( A, B ), where
// A = (minX + w/a) * (-a/c)
// B = (maxX + w/a) * (-a/c)
A = -(minX * a + w) / c;
B = -(maxX * a + w) / c;
rangeMinY = Math.max(minY, Math.min(A, B));
rangeMaxY = Math.min(maxY, Math.max(A, B));
// We have a possible solution for Case2 if the range for y is valid
if (rangeMinY <= rangeMaxY)
{
// Now that we have a valid range for y, we need to pick a value within
// that range.
//
// We calculate the value based on a custom condition.
//
// The custom condition that we use could be anything that defines
// another equation for x and y. Some examples are:
// "make x and y as close as possible": y = -w / ( a + c );
// "minimize abs(bx + dy)": y = -b * w / det
// "preserve aspect ratio": y = w / ( a * preferredX / preferredY + c );
if (Math.abs(det) < 1.0e-9)
{
// There is infinite number of solutions, lets pick x == y
y = -w / ( a + c );
}
else
{
// Minimize abs(bx + dy) - we need to solve:
// abs( b * ( -w - c * y ) / a + d * y ) = 0
// which gives us:
y = -b * w / det;
}
// Now that we have the y value calculated from the custom condition,
// we clamp with the range. This gives us a solution with
// values as close as possible to satisfy our custom condition when
// the condition is a linear function of x and y (in our case it is).
y = Math.max(rangeMinY, Math.min(y, rangeMaxY));
x = (-w - c * y) / a;
return new Point(x, y);
}
return null; // No solution
}
/**
* Calculates (x,y) such that the bounding box (0,0,x,y) transformed
* with <code>matrix</code> will have bounding box (0,0,w,h).
* x and y are restricted by <code>minX</code>, <code>maxX</code> and
* <code>minY</code>, <code>maxY</code>.
*
* When there is infinite number of solutions, the function will
* calculate x and y to be as close as possible.
*
* The functon assumes <code>minX >= 0</code> and <code>minY >= 0</code>
* (solution components x and y are non-negative).
*
* @return Point(x,y) or null if no solution exists.
*
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static public function calcUBoundsToFitTBounds(w:Number,
h:Number,
matrix:Matrix,
minX:Number,
minY:Number,
maxX:Number,
maxY:Number):Point
{
// Untransformed bounds size is (x,y). The corners of the untransformed
// bounding box are p1(0,0) p2(x,0) p3(0,y) p4(x,y).
// Matrix is | a c tx |
// | b d ty |
//
// After transfomation with the matrix those four points are:
// t1 = (0, 0) = matrix.deltaTransformPoint(p1)
// t2 = (ax, bx) = matrix.deltaTransformPoint(p2)
// t3 = (cy, dy) = matrix.deltaTransformPoint(p3)
// t4 = (ax + cy, cx + dy) = matrix.deltaTransformPoint(p4)
//
// The transformed bounds bounding box dimensions are (w,h):
// (1) w = max( t1.x, t2.x, t3.x, t4.x ) - min( t1.x, t2.x, t3.x, t4.x)
// (2) h = max( t1.y, t2.y, t3.y, t4.y ) - min( t1.y, t2.y, t3.y, t4.y)
//
// Looking at all the possible cases for min and max functions above,
// we can construct and solve simple linear systems for x and y.
// For example in the case of
// t1.x <= t2.x <= t3.x <= t4.x
// our first equation is
// (1) w = t4.x - t1.x <==> w = ax + cy
//
// To minimize the cases we're looking at we can take advantage of
// the limits we have: x >= 0, y >= 0;
// Taking into account these limits we deduce that:
// a*c >= 0 gives us (1) w = abs( t4.x - t1.x ) = abs( ax + cy )
// a*c < 0 gives us (1) w = abs( t2.x - t3.x ) = abs( ax - cy )
// b*d >= 0 gives us (2) h = abs( t4.y - t1.y ) = abs( bx + dy )
// b*d < 0 gives us (2) h = abs( t2.y - t3.y ) = abs( bx - dy )
//
// If we do a substitution such that
// c1 = a*c >= 0 ? c : -c
// d1 = b*d >= 0 ? d : -d
// we get the following linear system:
// (1) w = abs( ax + c1y )
// (2) h = abs( bx + d1y )
//
var a:Number = matrix.a;
var b:Number = matrix.b;
var c:Number = matrix.c;
var d:Number = matrix.d;
// If components are very close to zero, zero them out to handle the special cases
if (-1.0e-9 < a && a < +1.0e-9)
a = 0;
if (-1.0e-9 < b && b < +1.0e-9)
b = 0;
if (-1.0e-9 < c && c < +1.0e-9)
c = 0;
if (-1.0e-9 < d && d < +1.0e-9)
d = 0;
// Handle special cases.
if (b == 0 && c == 0)
{
// No solution in the following cases since the matrix collapses
// all points into a line.
if (a == 0 || d == 0)
return null;
// (1) w = abs( ax + cy ) <=> w = abs( ax ) <=> w = abs(a)x
// (2) h = abs( bx + dy ) <=> h = abs( dy ) <=> h = abs(d)y
return new Point(w / Math.abs(a), h / Math.abs(d));
}
if (a == 0 && d == 0)
{
// No solution in the following cases since the matrix collapses
// all points into a line.
if (b == 0 || c == 0)
return null;
// (1) w = abs( ax + cy ) <=> w = abs( cy ) <=> w = abs(c)y
// (2) h = abs( bx + dy ) <=> h = abs( bx ) <=> h = abs(b)x
return new Point(h / Math.abs(b), w / Math.abs(c));
}
// Handle general cases.
const c1:Number = ( a*c >= 0 ) ? c : -c;
const d1:Number = ( b*d >= 0 ) ? d : -d;
// we get the following linear system:
// (1) w = abs( ax + c1y )
// (2) h = abs( bx + d1y )
// Calculate the determinant of the system
const det:Number = a * d1 - b * c1;
if (Math.abs(det) < 1.0e-9)
{
// No solution in these cases since the matrix
// collapses all points into a line.
if (c1 == 0 || a == 0 || a == -c1)
return null;
if (Math.abs(a * h - b * w) > 1.0e-9)
return null; // No solution in this case
// Determinant is zero, the equations (1) & (2) are equivalent and
// we have only one equation:
// (1) w = abs( ax + c1y )
//
// Solve it finding x and y as close as possible:
return solveEquation(a, c1, w, minX, minX, maxX, maxY, b, d1);
}
// Pre-multiply w & h by the inverse dteterminant
const invDet:Number = 1 / det;
w *= invDet;
h *= invDet;
// Case 1:
// a * x + c1 * y >= 0
// b * x + d1 * y >= 0
var s:Point;
s = solveSystem(a, c1, b, d1, w, h);
if (s &&
minX <= s.x && s.x <= maxX && minY <= s.y && s.y <= maxY &&
a * s.x + c1 * s.x >= 0 &&
b * s.x + d1 * s.y >= 0)
return s;
// Case 2:
// a * x + c1 * y >= 0
// b * x + d1 * y < 0
s = solveSystem( a, c1, b, d1, w, -h);
if (s &&
minX <= s.x && s.x <= maxX && minY <= s.y && s.y <= maxY &&
a * s.x + c1 * s.x >= 0 &&
b * s.x + d1 * s.y < 0)
return s;
// Case 3:
// a * x + c1 * y < 0
// b * x + d1 * y >= 0
s = solveSystem( a, c1, b, d1, -w, h);
if (s &&
minX <= s.x && s.x <= maxX && minY <= s.y && s.y <= maxY &&
a * s.x + c1 * s.x < 0 &&
b * s.x + d1 * s.y >= 0)
return s;
// Case 4:
// a * x + c1 * y < 0
// b * x + d1 * y < 0
s = solveSystem( a, c1, b, d1, -w, -h);
if (s &&
minX <= s.x && s.x <= maxX && minY <= s.y && s.y <= maxY &&
a * s.x + c1 * s.x < 0 &&
b * s.x + d1 * s.y < 0)
return s;
return null; // No solution.
}
/**
* Determine if two Matrix instances are equal.
*
* @return true if the matrices are equal.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function isEqual(m1:Matrix, m2:Matrix):Boolean
{
return ((m1 && m2 &&
m1.a == m2.a &&
m1.b == m2.b &&
m1.c == m2.c &&
m1.d == m2.d &&
m1.tx == m2.tx &&
m1.ty == m2.ty) ||
(!m1 && !m2));
}
/**
* Determine if two Matrix3D instances are equal.
*
* @return true if the matrices are equal.
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
public static function isEqual3D(m1:Matrix3D, m2:Matrix3D):Boolean
{
if (m1 && m2 && m1.rawData.length == m2.rawData.length)
{
var r1:Vector.<Number> = m1.rawData;
var r2:Vector.<Number> = m2.rawData;
return (r1[0] == r2[0] &&
r1[1] == r2[1] &&
r1[2] == r2[2] &&
r1[3] == r2[3] &&
r1[4] == r2[4] &&
r1[5] == r2[5] &&
r1[6] == r2[6] &&
r1[7] == r2[7] &&
r1[8] == r2[8] &&
r1[9] == r2[9] &&
r1[10] == r2[10] &&
r1[11] == r2[11] &&
r1[12] == r2[12] &&
r1[13] == r2[13] &&
r1[14] == r2[14] &&
r1[15] == r2[15]);
}
return (!m1 && !m2);
}
/**
* Calculates (x,y) such as to satisfy the linear system:
* | a * x + c * y = m
* | b * x + d * y = n
*
* @param mOverDet <code>mOverDet must be equal to m / (a*d - b*c)</code>
* @param nOverDet <code>mOverDet must be equal to n / (a*d - b*c)</code>
*
* @return returns Point(x,y)
*
*
* @langversion 3.0
* @playerversion Flash 9
* @playerversion AIR 1.1
* @productversion Flex 3
*/
static private function solveSystem(a:Number,
c:Number,
b:Number,
d:Number,
mOverDet:Number,
nOverDet:Number):Point
{
return new Point(d * mOverDet - c * nOverDet,
a * nOverDet - b * mOverDet);
}
/**
* Workaround for player's concatenatedMatrix being wrong in some situations, such
* as when there is a filter or a scrollRect somewhere in the object's container
* hierarchy. Walk the parent tree manually, calculating the matrix manually.
*
* @param displayObject Calculate the concatenatedMatrix for this displayObject
*
* @param topParent <p>When specified, the matrix is computed up to the topParent,
* excluding topParent's concatenated matrix. This is useful when computing a transform
* in order to move an object to a different parent but the object's transform needs
* to be adjusted in order to keep its original position on screen.</p>
*
* @return The concatenatedMatrix for the displayObject
*
* @langversion 3.0
* @playerversion Flash 10
* @playerversion AIR 1.5
* @productversion Flex 4
*/
public static function getConcatenatedMatrix(displayObject:DisplayObject, topParent:DisplayObject):Matrix
{
return getConcatenatedMatrixHelper(displayObject, false, topParent);
}
/**
* Workaround for player's concatenatedMatrix being wrong in some situations, such
* as when there is a filter or a scrollRect somewhere in the object's container
* hierarchy. Walk the parent tree manually, calculating the matrix manually.
*
* This function differs from getConcatenatedMatrix in that it combines the
* computedMatrix of each ancestor. The computedMatrix includes transform offsets.
*
* @param displayObject Calculate the concatenatedMatrix for this displayObject
*
* @param topParent <p>When specified, the matrix is computed up to the topParent,
* excluding topParent's concatenated matrix. This is useful when computing a transform
* in order to move an object to a different parent but the object's transform needs
* to be adjusted in order to keep its original position on screen.</p>
*
* @return The concatenatedMatrix for the displayObject
*
* @langversion 3.0
* @playerversion Flash 10
* @playerversion AIR 1.5
* @productversion Flex 4
*/
public static function getConcatenatedComputedMatrix(displayObject:DisplayObject, topParent:DisplayObject):Matrix
{
return getConcatenatedMatrixHelper(displayObject, true, topParent);
}
/**
* @private
*/
private static function getConcatenatedMatrixHelper(displayObject:DisplayObject, useComputedMatrix:Boolean, topParent:DisplayObject):Matrix
{
var m:Matrix = new Matrix();
// This check should be made once per top-level ApplicationDomain
if (usesMarshalling == null)
{
// Check if marshalling support has been turned on
usesMarshalling = ApplicationDomain.currentDomain.hasDefinition("mx.managers.systemClasses.MarshallingSupport");
// If we aren't using marshalling, then we only have one ApplicationDomain and thus one class
// definition for UIComponent
if (!usesMarshalling && ApplicationDomain.currentDomain.hasDefinition("mx.core.UIComponent"))
uiComponentClass = Class(ApplicationDomain.currentDomain.getDefinition("mx.core.UIComponent"));
// same thing for UIMovieClip
if (!usesMarshalling && ApplicationDomain.currentDomain.hasDefinition("mx.flash.UIMovieClip"))
uiMovieClipClass = Class(ApplicationDomain.currentDomain.getDefinition("mx.flash.UIMovieClip"));
}
// Note, root will be "null" if the displayObject is off the display list. In particular,
// during start-up, before applicationComplete is dispatched, root will be null.
// Note that getConcatenatedMatrixHelper() with topParent == sandboxRoot will still work
// correctly in those cases as we use ".$parent" to walk up the parent chain and during start-up
// $parent will be null for the application before applicationComplete has been dispatched.
if (fakeDollarParent == null)
fakeDollarParent = new QName(mx_internal, "$parent");
if (useComputedMatrix && computedMatrixProperty == null)
computedMatrixProperty = new QName(mx_internal, "computedMatrix");
if ($transformProperty == null)
$transformProperty = new QName(mx_internal, "$transform");
var displayObjectMatrix:Matrix = displayObject ? displayObject.transform.matrix : null ;
var notTopAndHasMatrix:Boolean = displayObjectMatrix!=null && displayObject != topParent;
while (notTopAndHasMatrix)
{
var scrollRect:Rectangle = displayObject.scrollRect;
if (scrollRect != null)
m.translate(-scrollRect.x, -scrollRect.y);
// If we are using marshalling, we can have multiple class definitions of UIComponent
if (usesMarshalling && "moduleFactory" in displayObject)
{
var moduleFactory:Object = displayObject["moduleFactory"];
// If the module factory has changed, then we are in a different ApplicationDomain
if (moduleFactory && moduleFactory !== lastModuleFactory && "info" in moduleFactory)
{
var appDomain:ApplicationDomain;
appDomain = moduleFactory["info"]()["currentDomain"];
// Get the class definition for UIComponent in the current ApplicationDomain
if (appDomain && appDomain.hasDefinition("mx.core.UIComponent"))
uiComponentClass = Class(appDomain.getDefinition("mx.core.UIComponent"));
// same thing for UIMovieClip
if (appDomain && appDomain.hasDefinition("mx.flash.UIMovieClip"))
uiMovieClipClass = Class(appDomain.getDefinition("mx.flash.UIMovieClip"));
lastModuleFactory = moduleFactory;
}
}
var isUIComponent:Boolean = uiComponentClass && displayObject is uiComponentClass;
var isUIMovieClip:Boolean = uiMovieClipClass && displayObject is uiMovieClipClass;
if (useComputedMatrix && isUIComponent)
m.concat(displayObject[computedMatrixProperty]);
else if (isUIMovieClip)
m.concat(displayObject[$transformProperty].matrix);
else
m.concat(displayObjectMatrix);
// Try to access $parent, which is the true display list parent
if (isUIComponent)
displayObject = displayObject[fakeDollarParent] as DisplayObject;
else
displayObject = displayObject.parent as DisplayObject;
displayObjectMatrix = displayObject ? displayObject.transform.matrix : null;
notTopAndHasMatrix = displayObjectMatrix!=null && displayObject != topParent;
}
return m;
}
}
}