private void PrepareSLBitmap()
{
if (slBitmap != null)
{
slBitmap.Dispose();
}
int width = Math.Min(ClientSize.Width, ClientSize.Height) / 2;
if (width < 10)
{
slBitmap = null;
return;
}
// Prepare Bitmap
slBitmap = new Bitmap(width, width);
BitmapData bmData;
byte[] bytes;
BitmapReadBytes(slBitmap, out bytes, out bmData);
for (int y = 0; y < width; y++)
{
for (int x = 0; x < width; x++)
{
Color c = ColorMath.HslToRgb(new HslColor(hue, (byte)(x * 255 / width), (byte)(y * 255 / width)));
BitmapSetPixel(bytes, bmData, x, y, c);
}
}
BitmapWriteBytes(slBitmap, bytes, bmData);
}
private void PrepareWheelBitmap()
{
if (wheelBitmap != null)
{
wheelBitmap.Dispose();
}
int width = Math.Min(ClientSize.Width, ClientSize.Height);
Point center = new Point(width / 2, width / 2);
if (width < 10)
{
wheelBitmap = null;
return;
}
// Prepare Bitmap
wheelBitmap = new Bitmap(width, width);
// Fill background
Graphics g = Graphics.FromImage(wheelBitmap);
using (Brush b = new SolidBrush(Color.Transparent))
{
g.FillRectangle(b, 0, 0, width, width);
}
// Paint outer color wheel
double minDist = width / 2 * 0.78;
double maxDist = width / 2 - 1;
double factor = 128.0 / Math.PI; // map -pi...pi to 0...255 => map 0...pi to 0...128
BitmapData bmData;
byte[] bytes;
BitmapReadBytes(wheelBitmap, out bytes, out bmData);
for (int y = 0; y < width; y++)
{
for (int x = 0; x < width; x++)
{
double dist = GetDistance(new Point(x, y), center);
byte alpha;
if (dist < minDist - 0.5)
{
alpha = 0;
}
else if (dist < minDist + 0.5)
{
alpha = (byte)((0.5 - minDist + dist) * 255);
}
else if (dist < maxDist - 0.5)
{
alpha = 255;
}
else if (dist < maxDist + 0.5)
{
alpha = (byte)((0.5 + maxDist - dist) * 255);
}
else
{
alpha = 0;
}
if (alpha > 0)
{
double radAngle = Math.Atan2(y - center.Y, x - center.X);
// -pi -> -180° -> 192
// -pi/2 -> -90° -> 128
// 0 -> 0° -> 64
// pi/2 -> 90° -> 0
// pi -> 180° -> 192
//
// y = a * x + t;
// a = -1
// t = 192
byte hue = (byte)Mod((int)(-factor * radAngle + 192), 256);
Color c = Color.FromArgb(alpha, ColorMath.HslToRgb(new HslColor(hue, 255, 128)));
BitmapSetPixel(bytes, bmData, x, y, c);
}
}
}
BitmapWriteBytes(wheelBitmap, bytes, bmData);
}
//protected override void OnPaintBackground(PaintEventArgs pevent)
//{
// if (VisualStyleRenderer.IsSupported)
// {
// // The VisualStyleElement does not matter, we're only drawing the parent's background
// VisualStyleRenderer r = new VisualStyleRenderer(VisualStyleElement.Window.Dialog.Normal);
// r.DrawParentBackground(pevent.Graphics, ClientRectangle, this);
// }
// else
// {
// base.OnPaintBackground(pevent);
// }
//}
// NOTE: Other solution: http://dotnetrix.co.uk/custom.htm#tip3
protected override void OnPaint(PaintEventArgs pe)
{
// Draw outer color wheel bitmap
if (wheelBitmap != null)
{
pe.Graphics.DrawImage(wheelBitmap, new Point());
}
// Draw inner color bitmap
if (slBitmap != null)
{
pe.Graphics.DrawImage(slBitmap, new Point(slBitmap.Width / 2, slBitmap.Width / 2));
}
pe.Graphics.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;
// Draw hue marker
double radAngle = (double)hue / 128 * Math.PI + Math.PI / 2;
// sin(angle) = y / d
// cos(angle) = x / d
double d = 0.89 * wheelBitmap.Width / 2;
int x = (int)Math.Round(d * Math.Cos(radAngle));
int y = (int)-Math.Round(d * Math.Sin(radAngle));
// Map center-relative coordinates to window coordinates
x += wheelBitmap.Width / 2;
y += wheelBitmap.Width / 2;
Color c = ColorMath.ToGray(ColorMath.HslToRgb(new HslColor(hue, 255, 128))) > 128 ? Color.Black : Color.White;
using (Pen p = new Pen(c))
{
pe.Graphics.DrawEllipse(p, x - 3, y - 3, 6, 6);
}
// Draw secondary hue markers
if (secondaryHues != null)
{
foreach (byte sHue in secondaryHues)
{
radAngle = (double)sHue / 128 * Math.PI + Math.PI / 2;
// sin(angle) = y / d
// cos(angle) = x / d
d = 0.89 * wheelBitmap.Width / 2;
x = (int)Math.Round(d * Math.Cos(radAngle));
y = (int)-Math.Round(d * Math.Sin(radAngle));
// Map center-relative coordinates to window coordinates
x += wheelBitmap.Width / 2;
y += wheelBitmap.Width / 2;
c = ColorMath.ToGray(ColorMath.HslToRgb(new HslColor(sHue, 255, 128))) > 128 ? Color.Black : Color.White;
//using (Pen p = new Pen(Color.FromArgb(128, c)))
//{
// pe.Graphics.DrawRectangle(p, x - 2, y - 2, 4, 4);
//}
using (Brush b = new SolidBrush(Color.FromArgb(128, c)))
{
pe.Graphics.FillRectangle(b, x - 2, y - 2, 4, 4);
}
}
}
// Draw inner color marker
x = slBitmap.Width / 2 + saturation * (slBitmap.Width - 1) / 255;
y = slBitmap.Width / 2 + lightness * (slBitmap.Width - 1) / 255;
c = ColorMath.ToGray(ColorMath.HslToRgb(new HslColor(hue, saturation, lightness))) > 128 ? Color.Black : Color.White;
using (Pen p = new Pen(c))
{
pe.Graphics.DrawEllipse(p, x - 3, y - 3, 6, 6);
}
}