/**
* Finds the first occurance of a given color
*
* @param red the RGB red component, between 0 and 255 inclusive
* @param green the RGB green component, between 0 and 255 inclusive
* @param blue the RGB blue component, between 0 and 255 inclusive
* @return the color, or null if the color does not exist in this palette
*/
public HSSFColor findColor(byte red, byte green, byte blue) {
byte[] b = _palette.getColor(PaletteRecord.FIRST_COLOR_INDEX);
for (short i = PaletteRecord.FIRST_COLOR_INDEX; b != null; b = _palette.getColor(++i)) {
if (b[0] == red && b[1] == green && b[2] == blue) {
return new CustomColor(i, b);
}
}
return null;
}
/**
* Adds a new color into an empty color slot.
*
* @param red The red component
* @param green The green component
* @param blue The blue component
* @return The new custom color.
* @throws RuntimeException if there are more more free color indexes.
*/
public HSSFColor addColor(byte red, byte green, byte blue) {
byte[] b = _palette.getColor(PaletteRecord.FIRST_COLOR_INDEX);
short i;
for (i = PaletteRecord.FIRST_COLOR_INDEX;
i < PaletteRecord.STANDARD_PALETTE_SIZE + PaletteRecord.FIRST_COLOR_INDEX;
b = _palette.getColor(++i)) {
if (b == null) {
setColorAtIndex(i, red, green, blue);
return getColor(i);
}
}
throw new RuntimeException("Could not find free color index");
}
/**
* Finds the closest matching color in the custom palette. The method for finding the distance
* between the colors is fairly primative.
*
* @param red The red component of the color to match.
* @param green The green component of the color to match.
* @param blue The blue component of the color to match.
* @return The closest color or null if there are no custom colors currently defined.
*/
public HSSFColor findSimilarColor(int red, int green, int blue) {
HSSFColor result = null;
int minColorDistance = Integer.MAX_VALUE;
byte[] b = _palette.getColor(PaletteRecord.FIRST_COLOR_INDEX);
for (short i = PaletteRecord.FIRST_COLOR_INDEX; b != null; b = _palette.getColor(++i)) {
int colorDistance =
Math.abs(red - unsignedInt(b[0]))
+ Math.abs(green - unsignedInt(b[1]))
+ Math.abs(blue - unsignedInt(b[2]));
if (colorDistance < minColorDistance) {
minColorDistance = colorDistance;
result = getColor(i);
}
}
return result;
}
/**
* Retrieves the color at a given index
*
* @param index the palette index, between 0x8 to 0x40 inclusive
* @return the color, or null if the index is not populated
*/
public HSSFColor getColor(short index) {
// Handle the special AUTOMATIC case
if (index == HSSFColor.AUTOMATIC.index) {
return HSSFColor.AUTOMATIC.getInstance();
}
byte[] b = _palette.getColor(index);
if (b != null) {
return new CustomColor(index, b);
}
return null;
}
/**
* Sets the color at the given offset
*
* @param index the palette index, between 0x8 to 0x40 inclusive
* @param red the RGB red component, between 0 and 255 inclusive
* @param green the RGB green component, between 0 and 255 inclusive
* @param blue the RGB blue component, between 0 and 255 inclusive
*/
public void setColorAtIndex(short index, byte red, byte green, byte blue) {
_palette.setColor(index, red, green, blue);
}