/// <summary>
/// Increment the pixel count and add to the color information
/// </summary>
public void Increment ( Color32* pixel )
{
_pixelCount++ ;
_red += pixel->Red ;
_green += pixel->Green ;
_blue += pixel->Blue ;
}
/// <summary>
/// Return the palette index for the passed color
/// </summary>
public int GetPaletteIndex ( Color32* pixel , int level )
{
int paletteIndex = _paletteIndex ;
if ( !_leaf )
{
int shift = 7 - level ;
int index = ( ( pixel->Red & mask[level] ) >> ( shift - 2 ) ) |
( ( pixel->Green & mask[level] ) >> ( shift - 1 ) ) |
( ( pixel->Blue & mask[level] ) >> ( shift ) ) ;
if ( null != _children[index] )
paletteIndex = _children[index].GetPaletteIndex ( pixel , level + 1 ) ;
else
throw new Exception ( "Didn't expect this!" ) ;
}
return paletteIndex ;
}
/// <summary>
/// Add a color into the tree
/// </summary>
/// <param name="pixel">The color</param>
/// <param name="colorBits">The number of significant color bits</param>
/// <param name="level">The level in the tree</param>
/// <param name="octree">The tree to which this node belongs</param>
public void AddColor ( Color32* pixel , int colorBits , int level , Octree octree )
{
// Update the color information if this is a leaf
if ( _leaf )
{
Increment ( pixel ) ;
// Setup the previous node
octree.TrackPrevious ( this ) ;
}
else
{
// Go to the next level down in the tree
int shift = 7 - level ;
int index = ( ( pixel->Red & mask[level] ) >> ( shift - 2 ) ) |
( ( pixel->Green & mask[level] ) >> ( shift - 1 ) ) |
( ( pixel->Blue & mask[level] ) >> ( shift ) ) ;
OctreeNode child = _children[index] ;
if ( null == child )
{
// Create a new child node & store in the array
child = new OctreeNode ( level + 1 , colorBits , octree ) ;
_children[index] = child ;
}
// Add the color to the child node
child.AddColor ( pixel , colorBits , level + 1 , octree ) ;
}
}
/// <summary>
/// Get the palette index for the passed color
/// </summary>
/// <param name="pixel"></param>
/// <returns></returns>
public int GetPaletteIndex ( Color32* pixel )
{
return _root.GetPaletteIndex ( pixel , 0 ) ;
}
/// <summary>
/// Add a given color value to the octree
/// </summary>
/// <param name="pixel"></param>
public void AddColor ( Color32* pixel )
{
// Check if this request is for the same color as the last
if ( _previousColor == pixel->ARGB )
{
// If so, check if I have a previous node setup. This will only ocurr if the first color in the image
// happens to be black, with an alpha component of zero.
if ( null == _previousNode )
{
_previousColor = pixel->ARGB ;
_root.AddColor ( pixel , _maxColorBits , 0 , this ) ;
}
else
// Just update the previous node
_previousNode.Increment ( pixel ) ;
}
else
{
_previousColor = pixel->ARGB ;
_root.AddColor ( pixel , _maxColorBits , 0 , this ) ;
}
}
private byte QuantizePixel ( Color32* pixel, Octree octree )
{
byte paletteIndex = (byte)MaxColors ; // The color at [_maxColors] is set to transparent
// Get the palette index if this non-transparent
if ( pixel->Alpha > 0 )
paletteIndex = (byte)octree.GetPaletteIndex ( pixel ) ;
return paletteIndex ;
}