public static void RotateColors(IntPtr hwnd)
{
SafeDCHandle deviceContext = GetDCEx(
hwnd,
IntPtr.Zero,
DeviceContextValues.DCX_LOCKWINDOWUPDATE | DeviceContextValues.DCX_CACHE | DeviceContextValues.DCX_WINDOW);
if (deviceContext == SafeDCHandle.Null)
{
throw new Exception("Failed to get a device context");
}
bool rectResult = GetWindowRect(hwnd, out RECT rect);
if (!rectResult)
{
ThrowLoastWin32();
}
Console.WriteLine("Press Q to quit");
using (Graphics gr = Graphics.FromHdc(deviceContext.DangerousGetHandle()))
{
const int numSteps = 512;
const double max = 2 * Math.PI;
const double stepSize = max / numSteps;
const double center = 255f / 2;
const double rPhase = 0;
const double gPhase = 2 * Math.PI / 3;
const double bPhase = 2 * Math.PI / 3 * 2;
bool keepLooping = true;
while (keepLooping)
{
for (double theta = 0; theta <= max && keepLooping; theta += stepSize)
{
byte r = (byte)(Math.Sin(theta + rPhase) * center + center);
byte g = (byte)(Math.Sin(theta + gPhase) * center + center);
byte b = (byte)(Math.Sin(theta + bPhase) * center + center);
gr.FillRectangle(new SolidBrush(Color.FromArgb(r, g, b)), rect.left, rect.top, rect.right - rect.left, rect.bottom - rect.top);
Thread.Sleep(10);
while (Console.KeyAvailable)
{
var key = Console.ReadKey(true);
if (key.Key == ConsoleKey.Q)
{
Console.WriteLine("Exiting...");
keepLooping = false;
break;
}
}
}
}
}
_ = ReleaseDC(hwnd, deviceContext.HWnd);
}
/// <summary>Draws the image indicated by the given index on the specified <see cref="Graphics"/> at the specified location.</summary>
/// <param name="imageList">The image list.</param>
/// <param name="g">The <see cref="Graphics"/> to draw on.</param>
/// <param name="bounds">The bounds in which to draw the image. Set width and height to 0 to draw image at full size.</param>
/// <param name="index">The index of the image in the ImageList to draw.</param>
/// <param name="bgColor">
/// The background color of the image. This parameter can be a <see cref="Color"/> value or <see cref="COLORREF.None"/> so the image is drawn
/// transparently or <see cref="COLORREF.Default"/> so the image is drawn using the background color of the image list.
/// </param>
/// <param name="fgColor">
/// The foreground color of the image. This parameter can be a <see cref="Color"/> value or <see cref="COLORREF.None"/> so the image is blended
/// with the color of the destination device context or <see cref="COLORREF.Default"/> so the image is drawn using the system highlight color
/// as the foreground color.
/// </param>
/// <param name="style">The drawing style.</param>
/// <param name="overlayImageIndex">Optional index of an overlay image.</param>
/// <exception cref="System.ComponentModel.Win32Exception">Unable to draw the image with defined parameters.</exception>
public static void Draw(this ImageList imageList, Graphics g, Rectangle bounds, int index, COLORREF bgColor, COLORREF fgColor, IMAGELISTDRAWFLAGS style = IMAGELISTDRAWFLAGS.ILD_NORMAL, int overlayImageIndex = 0)
{
if (index < 0 || index >= imageList.Images.Count)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
if (overlayImageIndex < 0 || overlayImageIndex > imageList.GetOverlayCount())
{
throw new ArgumentOutOfRangeException(nameof(overlayImageIndex));
}
using (var hg = new SafeDCHandle(g))
{
var p = new IMAGELISTDRAWPARAMS(hg.DangerousGetHandle(), bounds, index, bgColor, style | (IMAGELISTDRAWFLAGS)INDEXTOOVERLAYMASK(overlayImageIndex))
{
rgbFg = fgColor
};
imageList.GetIImageList().Draw(p);
}
}
