38 * optional alpha components corresponding to each index. All components
39 * are represented in the colormap as 8-bit unsigned integral values.
40 * Some constructors allow the caller to specify "holes" in the colormap
41 * by indicating which colormap entries are valid and which represent
42 * unusable colors via the bits set in a {@code BigInteger} object.
43 * This color model is similar to an X11 PseudoColor visual.
44 * <p>
45 * Some constructors provide a means to specify an alpha component
46 * for each pixel in the colormap, while others either provide no
47 * such means or, in some cases, a flag to indicate whether the
48 * colormap data contains alpha values. If no alpha is supplied to
49 * the constructor, an opaque alpha component (alpha = 1.0) is
50 * assumed for each entry.
51 * An optional transparent pixel value can be supplied that indicates a
52 * pixel to be made completely transparent, regardless of any alpha
53 * component supplied or assumed for that pixel value.
54 * Note that the color components in the colormap of an
55 * {@code IndexColorModel} objects are never pre-multiplied with
56 * the alpha components.
57 * <p>
58 * <a name="transparency">
59 * The transparency of an {@code IndexColorModel} object is
60 * determined by examining the alpha components of the colors in the
61 * colormap and choosing the most specific value after considering
62 * the optional alpha values and any transparent index specified.
63 * The transparency value is {@code Transparency.OPAQUE}
64 * only if all valid colors in
65 * the colormap are opaque and there is no valid transparent pixel.
66 * If all valid colors
67 * in the colormap are either completely opaque (alpha = 1.0) or
68 * completely transparent (alpha = 0.0), which typically occurs when
69 * a valid transparent pixel is specified,
70 * the value is {@code Transparency.BITMASK}.
71 * Otherwise, the value is {@code Transparency.TRANSLUCENT}, indicating
72 * that some valid color has an alpha component that is
73 * neither completely transparent nor completely opaque
74 * (0.0 < alpha < 1.0).
75 * </a>
76 *
77 * <p>
78 * If an {@code IndexColorModel} object has
79 * a transparency value of {@code Transparency.OPAQUE},
80 * then the {@code hasAlpha}
81 * and {@code getNumComponents} methods
82 * (both inherited from {@code ColorModel})
83 * return false and 3, respectively.
84 * For any other transparency value,
85 * {@code hasAlpha} returns true
86 * and {@code getNumComponents} returns 4.
87 *
88 * <p>
89 * <a name="index_values">
90 * The values used to index into the colormap are taken from the least
91 * significant <em>n</em> bits of pixel representations where
92 * <em>n</em> is based on the pixel size specified in the constructor.
93 * For pixel sizes smaller than 8 bits, <em>n</em> is rounded up to a
94 * power of two (3 becomes 4 and 5,6,7 become 8).
95 * For pixel sizes between 8 and 16 bits, <em>n</em> is equal to the
96 * pixel size.
97 * Pixel sizes larger than 16 bits are not supported by this class.
98 * Higher order bits beyond <em>n</em> are ignored in pixel representations.
99 * Index values greater than or equal to the map size, but less than
100 * 2<sup><em>n</em></sup>, are undefined and return 0 for all color and
101 * alpha components.
102 * </a>
103 * <p>
104 * For those methods that use a primitive array pixel representation of
105 * type {@code transferType}, the array length is always one.
106 * The transfer types supported are {@code DataBuffer.TYPE_BYTE} and
107 * {@code DataBuffer.TYPE_USHORT}. A single int pixel
108 * representation is valid for all objects of this class, since it is
109 * always possible to represent pixel values used with this class in a
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38 * optional alpha components corresponding to each index. All components
39 * are represented in the colormap as 8-bit unsigned integral values.
40 * Some constructors allow the caller to specify "holes" in the colormap
41 * by indicating which colormap entries are valid and which represent
42 * unusable colors via the bits set in a {@code BigInteger} object.
43 * This color model is similar to an X11 PseudoColor visual.
44 * <p>
45 * Some constructors provide a means to specify an alpha component
46 * for each pixel in the colormap, while others either provide no
47 * such means or, in some cases, a flag to indicate whether the
48 * colormap data contains alpha values. If no alpha is supplied to
49 * the constructor, an opaque alpha component (alpha = 1.0) is
50 * assumed for each entry.
51 * An optional transparent pixel value can be supplied that indicates a
52 * pixel to be made completely transparent, regardless of any alpha
53 * component supplied or assumed for that pixel value.
54 * Note that the color components in the colormap of an
55 * {@code IndexColorModel} objects are never pre-multiplied with
56 * the alpha components.
57 * <p>
58 * <a id="transparency">
59 * The transparency of an {@code IndexColorModel} object is
60 * determined by examining the alpha components of the colors in the
61 * colormap and choosing the most specific value after considering
62 * the optional alpha values and any transparent index specified.
63 * The transparency value is {@code Transparency.OPAQUE}
64 * only if all valid colors in
65 * the colormap are opaque and there is no valid transparent pixel.
66 * If all valid colors
67 * in the colormap are either completely opaque (alpha = 1.0) or
68 * completely transparent (alpha = 0.0), which typically occurs when
69 * a valid transparent pixel is specified,
70 * the value is {@code Transparency.BITMASK}.
71 * Otherwise, the value is {@code Transparency.TRANSLUCENT}, indicating
72 * that some valid color has an alpha component that is
73 * neither completely transparent nor completely opaque
74 * (0.0 < alpha < 1.0).
75 * </a>
76 *
77 * <p>
78 * If an {@code IndexColorModel} object has
79 * a transparency value of {@code Transparency.OPAQUE},
80 * then the {@code hasAlpha}
81 * and {@code getNumComponents} methods
82 * (both inherited from {@code ColorModel})
83 * return false and 3, respectively.
84 * For any other transparency value,
85 * {@code hasAlpha} returns true
86 * and {@code getNumComponents} returns 4.
87 *
88 * <p>
89 * <a id="index_values">
90 * The values used to index into the colormap are taken from the least
91 * significant <em>n</em> bits of pixel representations where
92 * <em>n</em> is based on the pixel size specified in the constructor.
93 * For pixel sizes smaller than 8 bits, <em>n</em> is rounded up to a
94 * power of two (3 becomes 4 and 5,6,7 become 8).
95 * For pixel sizes between 8 and 16 bits, <em>n</em> is equal to the
96 * pixel size.
97 * Pixel sizes larger than 16 bits are not supported by this class.
98 * Higher order bits beyond <em>n</em> are ignored in pixel representations.
99 * Index values greater than or equal to the map size, but less than
100 * 2<sup><em>n</em></sup>, are undefined and return 0 for all color and
101 * alpha components.
102 * </a>
103 * <p>
104 * For those methods that use a primitive array pixel representation of
105 * type {@code transferType}, the array length is always one.
106 * The transfer types supported are {@code DataBuffer.TYPE_BYTE} and
107 * {@code DataBuffer.TYPE_USHORT}. A single int pixel
108 * representation is valid for all objects of this class, since it is
109 * always possible to represent pixel values used with this class in a
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