/// <summary>
/// Creates a new WriteableBitmap which is contrast adjusted version of this one and returns it.
/// </summary>
/// <param name="bmp">The WriteableBitmap.</param>
/// <param name="level">Level of contrast as double. [-255.0, 255.0] </param>
/// <returns>The new WriteableBitmap.</returns>
public static BitmapBuffer AdjustContrast(this BitmapBuffer bmp, double level)
{
int factor = (int)((259.0 * (level + 255.0)) / (255.0 * (259.0 - level)) * 255.0);
using (BitmapContext context = bmp.GetBitmapContext(ReadWriteMode.ReadOnly))
{
int nWidth = context.Width;
int nHeight = context.Height;
unsafe
{
NativeInt32Arr px1 = context.Pixels;
int * px = px1._inf32Buffer;
BitmapBuffer result = BitmapBufferFactory.New(nWidth, nHeight);
using (BitmapContext dest = result.GetBitmapContext())
{
NativeInt32Arr rp1 = dest.Pixels;
int * rp = rp1._inf32Buffer;
int len = context.Length;
for (int i = 0; i < len; i++)
{
// Extract
int c = px[i];
int a = (c >> 24) & 0xff;
int r = (c >> 16) & 0xff;
int g = (c >> 8) & 0xff;
int b = (c) & 0xff;
// Adjust contrast based on computed factor
//TODO: create lookup table for this
r = ((factor * (r - 128)) >> 8) + 128;
g = ((factor * (g - 128)) >> 8) + 128;
b = ((factor * (b - 128)) >> 8) + 128;
// Clamp
r = r < 0 ? 0 : r > 255 ? 255 : r;
g = g < 0 ? 0 : g > 255 ? 255 : g;
b = b < 0 ? 0 : b > 255 ? 255 : b;
// Set
rp[i] = (a << 24) | (r << 16) | (g << 8) | b;
}
}
return(result);
}
}
}
/// <summary>
/// Creates a new WriteableBitmap which is the grayscaled version of this one and returns it. The gray values are equal to the brightness values.
/// </summary>
/// <param name="bmp">The WriteableBitmap.</param>
/// <returns>The new gray WriteableBitmap.</returns>
public static BitmapBuffer Gray(this BitmapBuffer bmp)
{
using (BitmapContext context = bmp.GetBitmapContext(ReadWriteMode.ReadOnly))
{
int nWidth = context.Width;
int nHeight = context.Height;
unsafe
{
BitmapBuffer result = BitmapBufferFactory.New(nWidth, nHeight);
using (BitmapContext dest = result.GetBitmapContext())
{
NativeInt32Arr px1 = context.Pixels;
NativeInt32Arr rp1 = dest.Pixels;
int len = context.Length;
int * px = px1._inf32Buffer;
int * rp = rp1._inf32Buffer;
for (int i = 0; i < len; i++)
{
// Extract
int c = px[i];
int a = (c >> 24) & 0xff;
int r = (c >> 16) & 0xff;
int g = (c >> 8) & 0xff;
int b = (c) & 0xff;
// Convert to gray with constant factors 0.2126, 0.7152, 0.0722
r = g = b = ((r * 6966 + g * 23436 + b * 2366) >> 15);
// Set
rp[i] = (a << 24) | (r << 16) | (g << 8) | b;
}
}
return(result);
}
}
}
private static void AAWidthLine(int width, int height, BitmapContext context, float x1, float y1, float x2, float y2, float lineWidth, Int32 color, RectD?clipRect = null)
{
// Perform cohen-sutherland clipping if either point is out of the viewport
if (!CohenSutherlandLineClip(clipRect ?? new RectD(0, 0, width, height), ref x1, ref y1, ref x2, ref y2))
{
return;
}
if (lineWidth <= 0)
{
return;
}
unsafe
{
NativeInt32Arr buffer1 = context.Pixels;
int * buffer = buffer1._inf32Buffer;
if (y1 > y2)
{
Swap(ref x1, ref x2);
Swap(ref y1, ref y2);
}
if (x1 == x2)
{
x1 -= (int)lineWidth / 2;
x2 += (int)lineWidth / 2;
if (x1 < 0)
{
x1 = 0;
}
if (x2 < 0)
{
return;
}
if (x1 >= width)
{
return;
}
if (x2 >= width)
{
x2 = width - 1;
}
if (y1 >= height || y2 < 0)
{
return;
}
if (y1 < 0)
{
y1 = 0;
}
if (y2 >= height)
{
y2 = height - 1;
}
for (int x = (int)x1; x <= x2; x++)
{
for (int y = (int)y1; y <= y2; y++)
{
byte a = (byte)((color & 0xff000000) >> 24);
byte r = (byte)((color & 0x00ff0000) >> 16);
byte g = (byte)((color & 0x0000ff00) >> 8);
byte b = (byte)((color & 0x000000ff) >> 0);
byte rs, gs, bs;
byte rd, gd, bd;
int d;
rs = r;
gs = g;
bs = b;
d = buffer[y * width + x];
rd = (byte)((d & 0x00ff0000) >> 16);
gd = (byte)((d & 0x0000ff00) >> 8);
bd = (byte)((d & 0x000000ff) >> 0);
rd = (byte)((rs * a + rd * (0xff - a)) >> 8);
gd = (byte)((gs * a + gd * (0xff - a)) >> 8);
bd = (byte)((bs * a + bd * (0xff - a)) >> 8);
buffer[y * width + x] = (0xff << 24) | (rd << 16) | (gd << 8) | (bd << 0);
}
}
return;
}
if (y1 == y2)
{
if (x1 > x2)
{
Swap(ref x1, ref x2);
}
y1 -= (int)lineWidth / 2;
y2 += (int)lineWidth / 2;
if (y1 < 0)
{
y1 = 0;
}
if (y2 < 0)
{
return;
}
if (y1 >= height)
{
return;
}
if (y2 >= height)
{
y2 = height - 1;
}
if (x1 >= width || y2 < 0)
{
return;
}
if (x1 < 0)
{
x1 = 0;
}
if (x2 >= width)
{
x2 = width - 1;
}
for (int x = (int)x1; x <= x2; x++)
{
for (int y = (int)y1; y <= y2; y++)
{
byte a = (byte)((color & 0xff000000) >> 24);
byte r = (byte)((color & 0x00ff0000) >> 16);
byte g = (byte)((color & 0x0000ff00) >> 8);
byte b = (byte)((color & 0x000000ff) >> 0);
Byte rs, gs, bs;
Byte rd, gd, bd;
Int32 d;
rs = r;
gs = g;
bs = b;
d = buffer[y * width + x];
rd = (byte)((d & 0x00ff0000) >> 16);
gd = (byte)((d & 0x0000ff00) >> 8);
bd = (byte)((d & 0x000000ff) >> 0);
rd = (byte)((rs * a + rd * (0xff - a)) >> 8);
gd = (byte)((gs * a + gd * (0xff - a)) >> 8);
bd = (byte)((bs * a + bd * (0xff - a)) >> 8);
buffer[y * width + x] = (0xff << 24) | (rd << 16) | (gd << 8) | (bd << 0);
}
}
return;
}
y1 += 1;
y2 += 1;
float slope = (y2 - y1) / (x2 - x1);
float islope = (x2 - x1) / (y2 - y1);
float m = slope;
float w = lineWidth;
float dx = x2 - x1;
float dy = y2 - y1;
float xtot = (float)(w * dy / Math.Sqrt(dx * dx + dy * dy));
float ytot = (float)(w * dx / Math.Sqrt(dx * dx + dy * dy));
float sm = dx * dy / (dx * dx + dy * dy);
// Center it.
x1 += xtot / 2;
y1 -= ytot / 2;
x2 += xtot / 2;
y2 -= ytot / 2;
//
//
float sx = -xtot;
float sy = +ytot;
int ix1 = (int)x1;
int iy1 = (int)y1;
int ix2 = (int)x2;
int iy2 = (int)y2;
int ix3 = (int)(x1 + sx);
int iy3 = (int)(y1 + sy);
int ix4 = (int)(x2 + sx);
int iy4 = (int)(y2 + sy);
if (lineWidth == 2)
{
if (Math.Abs(dy) < Math.Abs(dx))
{
if (x1 < x2)
{
iy3 = iy1 + 2;
iy4 = iy2 + 2;
}
else
{
iy1 = iy3 + 2;
iy2 = iy4 + 2;
}
}
else
{
ix1 = ix3 + 2;
ix2 = ix4 + 2;
}
}
int starty = Math.Min(Math.Min(iy1, iy2), Math.Min(iy3, iy4));
int endy = Math.Max(Math.Max(iy1, iy2), Math.Max(iy3, iy4));
if (starty < 0)
{
starty = -1;
}
if (endy >= height)
{
endy = height + 1;
}
for (int y = starty + 1; y < endy - 1; y++)
{
leftEdgeX[y] = -1 << 16;
rightEdgeX[y] = 1 << 16 - 1;
}
AALineQ1(width, height, context, ix1, iy1, ix2, iy2, color, sy > 0, false);
AALineQ1(width, height, context, ix3, iy3, ix4, iy4, color, sy < 0, true);
if (lineWidth > 1)
{
AALineQ1(width, height, context, ix1, iy1, ix3, iy3, color, true, sy > 0);
AALineQ1(width, height, context, ix2, iy2, ix4, iy4, color, false, sy < 0);
}
if (x1 < x2)
{
if (iy2 >= 0 && iy2 < height)
{
rightEdgeX[iy2] = Math.Min(ix2, rightEdgeX[iy2]);
}
if (iy3 >= 0 && iy3 < height)
{
leftEdgeX[iy3] = Math.Max(ix3, leftEdgeX[iy3]);
}
}
else
{
if (iy1 >= 0 && iy1 < height)
{
rightEdgeX[iy1] = Math.Min(ix1, rightEdgeX[iy1]);
}
if (iy4 >= 0 && iy4 < height)
{
leftEdgeX[iy4] = Math.Max(ix4, leftEdgeX[iy4]);
}
}
//return;
for (int y = starty + 1; y < endy - 1; y++)
{
leftEdgeX[y] = Math.Max(leftEdgeX[y], 0);
rightEdgeX[y] = Math.Min(rightEdgeX[y], width - 1);
for (int x = leftEdgeX[y]; x <= rightEdgeX[y]; x++)
{
byte a = (byte)((color & 0xff000000) >> 24);
byte r = (byte)((color & 0x00ff0000) >> 16);
byte g = (byte)((color & 0x0000ff00) >> 8);
byte b = (byte)((color & 0x000000ff) >> 0);
Byte rs, gs, bs;
Byte rd, gd, bd;
Int32 d;
rs = r;
gs = g;
bs = b;
d = buffer[y * width + x];
rd = (byte)((d & 0x00ff0000) >> 16);
gd = (byte)((d & 0x0000ff00) >> 8);
bd = (byte)((d & 0x000000ff) >> 0);
rd = (byte)((rs * a + rd * (0xff - a)) >> 8);
gd = (byte)((gs * a + gd * (0xff - a)) >> 8);
bd = (byte)((bs * a + bd * (0xff - a)) >> 8);
buffer[y * width + x] = (0xff << 24) | (rd << 16) | (gd << 8) | (bd << 0);
}
}
}
}
