public static void Create(Control control, EInkCanvas canvas, int pollingIntervalMs)
{
if (control.Width > canvas.Width || control.Height > canvas.Height)
{
throw new Exception($"Control must be equal to or smaller than the device's canvas (device canvas is {canvas.Width}x{canvas.Height})");
}
var existingControl = _registeredControls.FirstOrDefault(c => c.Control == control);
if (existingControl != null)
{
existingControl.Timer.Stop();
_registeredControls.Remove(existingControl);
}
var registeredControl = new RegisteredInkControl()
{
Control = control,
Canvas = canvas,
Timer = new Timer()
{
Interval = pollingIntervalMs
}
};
registeredControl.Timer.Tick += (s, e) =>
{
var bmp = new Bitmap(canvas.Width, canvas.Height);
using (Graphics gb = Graphics.FromImage(bmp))
using (Graphics gc = Graphics.FromHwnd(control.Handle))
{
IntPtr hdcDest = IntPtr.Zero;
IntPtr hdcSrc = IntPtr.Zero;
try
{
hdcDest = gb.GetHdc();
hdcSrc = gc.GetHdc();
// BitBlt copies directly from the gfx buffer; gets around GDI vs DX rendering issues
BitBlt(hdcDest, 0, 0, canvas.Width, canvas.Height, hdcSrc, 0, 0, SRC_COPY);
}
finally
{
if (hdcDest != IntPtr.Zero)
{
gb.ReleaseHdc(hdcDest);
}
if (hdcSrc != IntPtr.Zero)
{
gc.ReleaseHdc(hdcSrc);
}
}
}
canvas.UpdateSurface(bmp);
};
registeredControl.Timer.Start();
_registeredControls.Add(registeredControl);
}
public static void RegisterForInk(this Control control, EInkCanvas canvas, int pollingIntervalMs = 500)
{
RegisteredInkControl.Create(control, canvas, pollingIntervalMs);
}
