public static IPixelCanvas Blit(IPixelCanvas first, IPixelCanvas second, BlendMode blendMode)
{
var pc = new PixelArrayCanvas(first.Width, first.Height);
pc.Blit(second, blendMode);
return pc;
}
/// <summary>
/// http://en.wikipedia.org/wiki/Alpha_compositing
/// </summary>
/// <param name="destination_rect"></param>
/// <param name="source"></param>
/// <param name="source_rect"></param>
/// <param name="alpha"></param>
/// <param name="red"></param>
/// <param name="green"></param>
/// <param name="blue"></param>
/// <param name="blendMode"></param>
public static void DEBUG__Blit(
this IPixelCanvas pc,
Rectangle destination_rect,
IPixelCanvas source,
Rect source_rect,
byte alpha,
byte red,
byte green,
byte blue,
BlendMode blendMode)
{
int debug_counter = 0;
var debug_destination_pc = new PixelArrayCanvas(pc.Width, pc.Height);
debug_destination_pc.Blit(pc, BlendMode.Copy);
debug_destination_pc.Save(@"c:\temp\blend\{0}_destination.bmp".FormatWith(debug_counter));
var debug_source_pc = new PixelArrayCanvas(source.Width, source.Height);
debug_source_pc.Blit(pc, BlendMode.Copy);
debug_source_pc.Save(@"c:\temp\blend\{0}_source.bmp".FormatWith(debug_counter));
// http://keithp.com/~keithp/porterduff/p253-porter.pdf
// http://en.wikipedia.org/wiki/Alpha_compositing
// tint with transparent color, nothing to do here, since this would make every source pixel transparent
if (alpha == 0)
return;
if (!pc.IntersectsWith(destination_rect))
return;
// tinted if color is not opaque white
var is_tinted = alpha != 255 || red != 255 || green != 255 || blue != 255;
var source_width = source.Width;
var source_pixels = source;
var source_length = source.Length;
int source_rectangle_x = (int)source_rect.X;
int source_rectangle_y = (int)source_rect.Y;
var destination_width = pc.Width;
var destination_height = pc.Height;
var destination_pixels = pc;
var destination_length = pc.Length;
int destination_rectangle_x = (int)destination_rect.X;
int destination_rectangle_y = (int)destination_rect.Y;
int destination_rect_width = (int)destination_rect.Width;
int destination_rect_height = (int)destination_rect.Height;
int sourceIdx = -1;
int idx;
double ii;
double jj;
int source_pixel = 0;
int source_alpha = 0;
int source_red = 0;
int source_green = 0;
int source_blue = 0;
int destination_alpha;
int destination_red;
int destination_green;
int destination_blue;
var source_rectangle_width = source_rect.Width;
var sdx = source_rect.Width / destination_rect.Width;
var sdy = source_rect.Height / destination_rect.Height;
int lastii = -1;
int lastjj = -1;
jj = source_rectangle_y;
int current_x;
int current_y = destination_rectangle_y;
// each row in destination rectangle
for (int destination_rect_row = 0; destination_rect_row < destination_rect_height; destination_rect_row++)
{
// check if current y is within destination rectangle bounds (todo: >= 0? should it be destination_rect_y ?)
if (current_y >= 0 && current_y < destination_height)
{
ii = source_rectangle_x;
idx = destination_rectangle_x + current_y * destination_width;
// start from left most column in destination rectangle
current_x = destination_rectangle_x;
// each column in destination rectangle
for (int destination_rect_col = 0; destination_rect_col < destination_rect_width; destination_rect_col++)
{
// todo: >= 0?
if (current_x >= 0 && current_x < destination_width)
{
if ((int)ii != lastii || (int)jj != lastjj)
{
sourceIdx = (int)ii + (int)jj * source_width;
if (sourceIdx >= 0 && sourceIdx < source_length)
{
// retrieve current source pixel and it's channels values
source_pixel = source_pixels[sourceIdx];
if (blendMode == BlendMode.Copy)
{
destination_pixels[idx] = source_pixel;
current_x++;
idx++;
ii += sdx;
continue;
}
if (source_pixel != 0)
{
source_alpha = ((source_pixel >> 24) & 0xff);
source_red = ((source_pixel >> 16) & 0xff);
source_green = ((source_pixel >> 8) & 0xff);
source_blue = ((source_pixel) & 0xff);
// tint the pixel if needed
if (is_tinted && source_alpha != 0)
{
source_alpha = (((source_alpha * alpha) * 0x8081) >> 23);
source_red = ((((((source_red * red) * 0x8081) >> 23) * alpha) * 0x8081) >> 23);
source_green = ((((((source_green * green) * 0x8081) >> 23) * alpha) * 0x8081) >> 23);
source_blue = ((((((source_blue * blue) * 0x8081) >> 23) * alpha) * 0x8081) >> 23);
source_pixel = (source_alpha << 24) | (source_red << 16) | (source_green << 8) | source_blue;
}
}
else
{
source_alpha = 0;
}
}
else
{
source_alpha = 0;
}
}
if (source_alpha == 0)
{
current_x++;
idx++;
ii += sdx;
continue;
}
else
{
// get destination pixel
int destPixel = destination_pixels[idx];
destination_alpha = ((destPixel >> 24) & 0xff);
// destination is transparent or source is opaque,
// just replace destination pixel with source pixel
if (blendMode == BlendMode.Alpha && (source_alpha == 255 || destination_alpha == 0))
{
// debug code
debug_counter++;
debug_destination_pc[idx] = pc.GetColor(System.Windows.Media.Colors.Red);
debug_source_pc[sourceIdx] = pc.GetColor(System.Windows.Media.Colors.Red);
debug_destination_pc.Save(@"c:\temp\blend\{0}_destination.bmp".FormatWith(debug_counter));
debug_source_pc.Save(@"c:\temp\blend\{0}_source.bmp".FormatWith(debug_counter));
// end debug code
destination_pixels[idx] = source_pixel;
current_x++;
idx++;
ii += sdx;
continue;
}
// get destination pixel rgb values
destination_red = ((destPixel >> 16) & 0xff);
destination_green = ((destPixel >> 8) & 0xff);
destination_blue = ((destPixel) & 0xff);
if (blendMode == BlendMode.Alpha)
{
var isa = 255 - source_alpha;
// debug code
debug_destination_pc[idx] = pc.GetColor(System.Windows.Media.Colors.Red);
debug_source_pc[sourceIdx] = pc.GetColor(System.Windows.Media.Colors.Red);
var deb_part = new PixelArrayCanvas(3, 1);
deb_part[0] = source_pixel;
deb_part[1] = destPixel;
// end debug code
destPixel = (((((source_alpha << 8) + isa * destination_alpha) >> 8) & 0xff) << 24) |
(((((source_red << 8) + isa * destination_red) >> 8) & 0xff) << 16) |
(((((source_green << 8) + isa * destination_green) >> 8) & 0xff) << 8) |
((((source_blue << 8) + isa * destination_blue) >> 8) & 0xff);
// debug code
deb_part[2] = destPixel;
debug_counter++;
debug_destination_pc.Save(@"c:\temp\blend\{0}_destination.bmp".FormatWith(debug_counter));
debug_source_pc.Save(@"c:\temp\blend\{0}_source.bmp".FormatWith(debug_counter));
deb_part.Save(@"c:\temp\blend\{0}_blend.bmp".FormatWith(debug_counter));
//end debug code
}
else
throw new NotSupportedException();
destination_pixels[idx] = destPixel;
}
}
current_x++;
idx++;
ii += sdx;
}
}
jj += sdy;
current_y++;
}
// debug code
debug_destination_pc.Save(@"c:\temp\blend\final_destination.bmp".FormatWith(debug_counter));
debug_source_pc.Save(@"c:\temp\blend\final_source.bmp".FormatWith(debug_counter));
pc.Save(@"c:\temp\blend\final_blend.bmp".FormatWith(debug_counter));
// end debug code
}
public static void DrawGeometry(
this IPixelCanvas pc,
int x,
int y,
Geometry geometry,
Brush fillBrush,
Pen pen,
BlendMode blendMode)
{
var size = geometry.GetRenderBounds(pen).Size;
var width = (int)size.Width;
var height = (int)size.Height;
var bmp =
geometry.RenderToBitmap(
size,
new Point(),
size,
fillBrush,
pen,
PixelFormats.Pbgra32);
int[] pixels;
if (blendMode == BlendMode.Copy && width == pc.Width && height == pc.Height)
{
pixels = pc.GetPixels();
bmp.CopyPixels(pixels, pc.Stride, 0);
}
else
{
var pc2 = new PixelArrayCanvas(width, height);
pixels = pc2.GetPixels();
bmp.CopyPixels(pixels, pc2.Stride, 0);
pc.Blit(
new Rectangle(x, y, width, height),
pc2,
new Rectangle(0, 0, width, height),
255, 255, 255, 255, blendMode);
}
}
public static void DrawVisual(this IPixelCanvas pc, int x, int y, ContainerVisual visual, BlendMode blendMode)
{
if (visual.ContentBounds.IsEmpty)
return;
var width = (int)visual.ContentBounds.Width;
var height = (int)visual.ContentBounds.Height;
var bmp = visual.RenderToBitmap(visual.ContentBounds.Size, new Point(0, 0));
if (blendMode == BlendMode.Copy && width == pc.Width && height == pc.Height)
{
var pac = pc as PixelArrayCanvas;
if(pac == null)
{
throw new NotSupportedException("BlendMode.Copy is only supported with PixelArrayCanvas");
}
bmp.CopyPixels(pac.Pixels, pc.Stride, 0);
}
else
{
var sw = Stopwatch.StartNew();
var pc2 = new PixelArrayCanvas(width, height);
bmp.CopyPixels(pc2.Pixels, pc2.Stride, 0);
Debug.WriteLine("Copy Pixels " + sw.GetElapsedAndRestart().TotalMilliseconds);
pc.Blit(
new Rectangle(x, y, width, height),
pc2,
new Rectangle(0, 0, width, height),
255, 255, 255, 255, blendMode);
Debug.WriteLine("Blit " + sw.GetElapsedAndRestart().TotalMilliseconds);
}
}
public static void DrawLine(this IPixelCanvas pc, int x1, int y1, int x2, int y2, System.Windows.Media.Color color, double width)
{
var l = new Shapes.Line();
l.X1 = x1;
l.Y1 = y1;
l.X2 = x2;
l.Y2 = y2;
l.Stroke = new SolidColorBrush(color);
l.StrokeThickness = width;
l.Arrange(pc.Bounds.ToRect());
var sw = Stopwatch.StartNew();
var bitmap_source = l.RenderToBitmap(pc.Bounds.ToSize(), new Point(x1, y1));
var pixels = new int[pc.Length];
bitmap_source.CopyPixels(pixels, pc.Stride, 0);
var pc2 = new PixelArrayCanvas(pc.Width, pc.Height);
pc2.ReplaceFromPixels(pixels, pc.Width, pc.Height);
pc.Blit(pc2, BlendMode.Alpha);
}
