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RatioUtil

Kind of class:	public class
Package:	org.casalib.util
Inherits from:	none
Version:	08/29/08
Author:	Aaron Clinger
Classpath:	org.casalib.util.RatioUtil
File last modified:	Monday, 01 December 2008, 11:16:36

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/*
    CASA Lib for ActionScript 3.0
    Copyright (c) 2008, Aaron Clinger & Contributors of CASA Lib
    All rights reserved.
    
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:
    
    - Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    
    - Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    
    - Neither the name of the CASA Lib nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.
    
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/
package org.casalib.util {
    import flash.geom.Rectangle;
    import org.casalib.math.Percent;
    
    /**
        Provides utility functions for ratio scaling.
        
        @author Aaron Clinger
        @version 08/29/08
    */
    public class RatioUtil {
        
        /**
            Determines the ratio of width to height.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
        */
        public static function widthToHeight(size:Rectangle):Number {
            return size.width / size.height;
        }
        
        /**
            Determines the ratio of height to width.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
        */
        public static function heightToWidth(size:Rectangle):Number {
            return size.height / size.width;
        }
        
        /**
            Scales an area's width and height while preserving aspect ratio.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
            @param amount: The amount you wish to scale by.
        */
        public static function scale(size:Rectangle, amount:Percent):Rectangle {
            var scaled:Rectangle = size.clone();
            
            scaled.width  *= amount.decimalPercentage;
            scaled.height *= amount.decimalPercentage;
            
            return scaled;
        }
        
        /**
            Scales the width of an area while preserving aspect ratio.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
            @param height: The new height of the area.
        */
        public static function scaleWidth(size:Rectangle, height:Number):Rectangle {
            var scaled:Rectangle = size.clone();
            var ratio:Number     = RatioUtil.widthToHeight(size);
            
            scaled.width  = height * ratio;
            scaled.height = height;
            
            return scaled;
        }
        
        /**
            Scales the height of an area while preserving aspect ratio.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
            @param width: The new width of the area.
        */
        public static function scaleHeight(size:Rectangle, width:Number):Rectangle {
            var scaled:Rectangle = size.clone();
            var ratio:Number     = RatioUtil.heightToWidth(size);
            
            scaled.width  = width;
            scaled.height = width * ratio;
            
            return scaled;
        }
        
        /**
            Resizes an area to fill the bounding area while preserving aspect ratio.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
            @param bounds: The area to fill. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
        */
        public static function scaleToFill(size:Rectangle, bounds:Rectangle):Rectangle {
            var scaled:Rectangle = RatioUtil.scaleHeight(size, bounds.width);
            
            if (scaled.height < bounds.height)
                scaled = RatioUtil.scaleWidth(size, bounds.height);
            
            return scaled;
        }
        
        /**
            Resizes an area to the maximum size of a bounding area without exceeding while preserving aspect ratio.
            
            @param size: The area's width and height expressed as a {@code Rectangle}. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
            @param bounds: The area the rectangle needs to fit within. The {@code Rectangle}'s {@code x} and {@code y} values are ignored.
        */
        public static function scaleToFit(size:Rectangle, bounds:Rectangle):Rectangle {
            var scaled:Rectangle = RatioUtil.scaleHeight(size, bounds.width);
            
            if (scaled.height > bounds.height)
                scaled = RatioUtil.scaleWidth(size, bounds.height);
            
            return scaled;
        }
    }
}

Provides utility functions for ratio scaling.

Summary

Class methods

widthToHeight (size:Rectangle) : Number
- Determines the ratio of width to height.
heightToWidth (size:Rectangle) : Number
- Determines the ratio of height to width.
scale (size:Rectangle, amount:Percent) : Rectangle
- Scales an area's width and height while preserving aspect ratio.
scaleWidth (size:Rectangle, height:Number) : Rectangle
- Scales the width of an area while preserving aspect ratio.
scaleHeight (size:Rectangle, width:Number) : Rectangle
- Scales the height of an area while preserving aspect ratio.
scaleToFill (size:Rectangle, bounds:Rectangle) : Rectangle
- Resizes an area to fill the bounding area while preserving aspect ratio.
scaleToFit (size:Rectangle, bounds:Rectangle) : Rectangle
- Resizes an area to the maximum size of a bounding area without exceeding while preserving aspect ratio.

Class methods

heightToWidth

public static function heightToWidth (

size:Rectangle) : Number

Determines the ratio of height to width.

Parameters:

size:

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

scale

public static function scale (

size:Rectangle, amount:Percent) : Rectangle

Scales an area's width and height while preserving aspect ratio.

Parameters:

size :

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

amount:

The amount you wish to scale by.

scaleHeight

public static function scaleHeight (

size:Rectangle, width:Number) : Rectangle

Scales the height of an area while preserving aspect ratio.

Parameters:

size :

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

width:

The new width of the area.

scaleToFill

public static function scaleToFill (

size:Rectangle, bounds:Rectangle) : Rectangle

Resizes an area to fill the bounding area while preserving aspect ratio.

Parameters:

size :

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

bounds:

The area to fill. The Rectangle's x and y values are ignored.

scaleToFit

public static function scaleToFit (

size:Rectangle, bounds:Rectangle) : Rectangle

Resizes an area to the maximum size of a bounding area without exceeding while preserving aspect ratio.

Parameters:

size :

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

bounds:

The area the rectangle needs to fit within. The Rectangle's x and y values are ignored.

scaleWidth

public static function scaleWidth (

size:Rectangle, height:Number) : Rectangle

Scales the width of an area while preserving aspect ratio.

Parameters:

size :

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.

height:

The new height of the area.

widthToHeight

public static function widthToHeight (

size:Rectangle) : Number

Determines the ratio of width to height.

Parameters:

size:

The area's width and height expressed as a Rectangle. The Rectangle's x and y values are ignored.