public void Overwrite(
Gdi32.DeviceContextSafeHandle bitmapDC,
Gdi32.DeviceContextSafeHandle windowDC,
int windowClientLeft,
int windowClientTop,
int windowClientWidth,
int windowClientHeight,
uint windowDpi,
uint zOrder)
{
if (windowClientWidth > 0 && windowClientHeight > 0)
{
if (bitmap is null || bitmapWidth < windowClientWidth || bitmapHeight < windowClientHeight)
{
if (bitmap is null)
{
// Most of the time, windows don't resize, so save some space by not rounding up.
bitmapWidth = windowClientWidth;
bitmapHeight = windowClientHeight;
}
else
{
// Round up to the nearest 256 pixels to minimize the number of times that bitmaps are
// reallocated.
bitmapWidth = ((Math.Max(bitmapWidth, windowClientWidth) + 255) / 256) * 256;
bitmapHeight = ((Math.Max(bitmapHeight, windowClientHeight) + 255) / 256) * 256;
bitmap.Dispose();
}
bitmap = Gdi32.CreateDIBSection(windowDC, new()
{
bmiHeader =
{
biSize = Marshal.SizeOf <Gdi32.BITMAPINFOHEADER>(),
biWidth = bitmapWidth,
biHeight = -bitmapHeight,
biPlanes = 1,
biBitCount = BitsPerPixel,
},
}, Gdi32.DIB.RGB_COLORS, ppvBits: out _, hSection: IntPtr.Zero, offset: 0).ThrowLastErrorIfInvalid();
}
Gdi32.SelectObject(bitmapDC, bitmap).ThrowWithoutLastErrorAvailableIfInvalid(nameof(Gdi32.SelectObject));
if (!Gdi32.BitBlt(bitmapDC, 0, 0, windowClientWidth, windowClientHeight, windowDC, 0, 0, Gdi32.RasterOperation.SRCCOPY))
{
throw new Win32Exception();
}
}
WindowClientLeft = windowClientLeft;
WindowClientTop = windowClientTop;
WindowClientWidth = windowClientWidth;
WindowClientHeight = windowClientHeight;
WindowDpi = windowDpi;
ZOrder = zOrder;
}
public void AddFrame(
Gdi32.DeviceContextSafeHandle bitmapDC,
int windowClientLeft,
int windowClientTop,
int windowClientWidth,
int windowClientHeight,
uint windowDpi,
uint zOrder)
{
if (windowDC is null)
{
throw new InvalidOperationException("The window is closed.");
}
var frame = frames.GetNextRef() ??= new();
frame.Overwrite(bitmapDC, windowDC, windowClientLeft, windowClientTop, windowClientWidth, windowClientHeight, windowDpi, zOrder);
}
public void Compose(Gdi32.DeviceContextSafeHandle bitmapDC, Gdi32.DeviceContextSafeHandle compositionDC, (int X, int Y) compositionOffset)
