poi-scratchpad/src/main/java/org/apache/poi/hwmf/record/HwmfMapMode.java

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   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

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   distributed under the License is distributed on an "AS IS" BASIS,
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   See the License for the specific language governing permissions and
   limitations under the License.
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package org.apache.poi.hwmf.record;

/**
 * A 16-bit unsigned integer that defines the mapping mode.
 *
 * The MapMode defines how logical units are mapped to physical units;
 * that is, assuming that the origins in both the logical and physical coordinate systems
 * are at the same point on the drawing surface, what is the physical coordinate (x',y')
 * that corresponds to logical coordinate (x,y).
 *
 * For example, suppose the mapping mode is MM_TEXT. Given the following definition of that
 * mapping mode, and an origin (0,0) at the top left corner of the drawing surface, logical
 * coordinate (4,5) would map to physical coordinate (4,5) in pixels.
 *
 * Now suppose the mapping mode is MM_LOENGLISH, with the same origin as the previous
 * example. Given the following definition of that mapping mode, logical coordinate (4,-5)
 * would map to physical coordinate (0.04,0.05) in inches.
 */
public enum HwmfMapMode {
    /**
     *  Each logical unit is mapped to one device pixel.
     *  Positive x is to the right; positive y is down.
     */
    MM_TEXT(0x0001, 0),
    
    /**
     *  Each logical unit is mapped to 0.1 millimeter.
     *  Positive x is to the right; positive y is up.
     */
    MM_LOMETRIC(0x0002, 254),
    
    /**
     *  Each logical unit is mapped to 0.01 millimeter.
     *  Positive x is to the right; positive y is up.
     */
    MM_HIMETRIC(0x0003, 2540),
    
    /**
     *  Each logical unit is mapped to 0.01 inch.
     *  Positive x is to the right; positive y is up.
     */
    MM_LOENGLISH(0x0004, 100),
    
    /**
     *  Each logical unit is mapped to 0.001 inch.
     *  Positive x is to the right; positive y is up.
     */
    MM_HIENGLISH(0x0005, 1000),
    
    /**
     *  Each logical unit is mapped to one twentieth (1/20) of a point.
     *  In printing, a point is 1/72 of an inch; therefore, 1/20 of a point is 1/1440 of an inch.
     *  This unit is also known as a "twip".
     *  Positive x is to the right; positive y is up.
     */
    MM_TWIPS(0x0006, 1440),
    
    /**
     *  Logical units are mapped to arbitrary device units with equally scaled axes;
     *  that is, one unit along the x-axis is equal to one unit along the y-axis.
     *  The META_SETWINDOWEXT and META_SETVIEWPORTEXT records specify the units and the
     *  orientation of the axes.
     *  The processing application SHOULD make adjustments as necessary to ensure the x and y
     *  units remain the same size. For example, when the window extent is set, the viewport
     *  SHOULD be adjusted to keep the units isotropic.
     */
    MM_ISOTROPIC(0x0007, -1),
    
    /**
     *  Logical units are mapped to arbitrary units with arbitrarily scaled axes.
     */
    MM_ANISOTROPIC(0x0008, -1);
    
    /**
     * native flag
     */
    public final int flag;
    
    /**
     * transformation units - usually scale relative to current dpi.
     * when scale == 0, then don't scale
     * when scale == -1, then scale relative to window dimension. 
     */
    public final int scale;
    
    HwmfMapMode(int flag, int scale) {
        this.flag = flag;
        this.scale = scale;
    }

    public static HwmfMapMode valueOf(int flag) {
        for (HwmfMapMode mm : values()) {
            if (mm.flag == flag) return mm;
        }
        return MM_ISOTROPIC;
    }        
}