@Override
protected void paintDirect(BufferedImage buf, Rectangle bounds) {
// TODO: paint frame decoration if window is decorated
Window win = SwingUtilities.getWindowAncestor(this);
GDI32 gdi = GDI32.INSTANCE;
User32 user = User32.INSTANCE;
int x = bounds.x;
int y = bounds.y;
Point origin = SwingUtilities.convertPoint(this, x, y, win);
int w = bounds.width;
int h = bounds.height;
int ww = win.getWidth();
int wh = win.getHeight();
HDC screenDC = user.GetDC(null);
HANDLE oldBitmap = null;
try {
if (memDC == null) {
memDC = gdi.CreateCompatibleDC(screenDC);
}
if (hBitmap == null || !win.getSize().equals(bitmapSize)) {
if (hBitmap != null) {
gdi.DeleteObject(hBitmap);
hBitmap = null;
}
BITMAPINFO bmi = new BITMAPINFO();
bmi.bmiHeader.biWidth = ww;
bmi.bmiHeader.biHeight = wh;
bmi.bmiHeader.biPlanes = 1;
bmi.bmiHeader.biBitCount = 32;
bmi.bmiHeader.biCompression = WinGDI.BI_RGB;
bmi.bmiHeader.biSizeImage = ww * wh * 4;
PointerByReference ppbits = new PointerByReference();
hBitmap = gdi.CreateDIBSection(memDC, bmi,
WinGDI.DIB_RGB_COLORS,
ppbits, null, 0);
pbits = ppbits.getValue();
bitmapSize = new Dimension(ww, wh);
}
oldBitmap = gdi.SelectObject(memDC, hBitmap);
Raster raster = buf.getData();
int[] pixel = new int[4];
int[] bits = new int[w];
for (int row = 0; row < h; row++) {
for (int col = 0; col < w; col++) {
raster.getPixel(col, row, pixel);
int alpha = (pixel[3] & 0xFF) << 24;
int red = (pixel[2] & 0xFF);
int green = (pixel[1] & 0xFF) << 8;
int blue = (pixel[0] & 0xFF) << 16;
bits[col] = alpha | red | green | blue;
}
int v = wh - (origin.y + row) - 1;
pbits.write((v*ww+origin.x)*4, bits, 0, bits.length);
}
SIZE winSize = new SIZE();
winSize.cx = win.getWidth();
winSize.cy = win.getHeight();
POINT winLoc = new POINT();
winLoc.x = win.getX();
winLoc.y = win.getY();
POINT srcLoc = new POINT();
BLENDFUNCTION blend = new BLENDFUNCTION();
HWND hWnd = getHWnd(win);
// extract current constant alpha setting, if possible
ByteByReference bref = new ByteByReference();
IntByReference iref = new IntByReference();
byte level = getAlpha(win);
try {
// GetLayeredwindowAttributes supported WinXP and later
if (user.GetLayeredWindowAttributes(hWnd, null, bref, iref)
&& (iref.getValue() & User32.LWA_ALPHA) != 0) {
level = bref.getValue();
}
}
catch(UnsatisfiedLinkError e) {
}
blend.SourceConstantAlpha = level;
blend.AlphaFormat = User32.AC_SRC_ALPHA;
user.UpdateLayeredWindow(hWnd, screenDC, winLoc, winSize, memDC,
srcLoc, 0, blend, User32.ULW_ALPHA);
}
finally {
user.ReleaseDC(null, screenDC);
if (memDC != null && oldBitmap != null) {
gdi.SelectObject(memDC, oldBitmap);
}
}
}