// Use double buffer to reduce flicker when drawing complex ROIs.
// Author: Erik Meijering
void paintDoubleBuffered(Graphics g) {
final int srcRectWidthMag = (int) (srcRect.width * magnification);
final int srcRectHeightMag = (int) (srcRect.height * magnification);
if (offScreenImage == null
|| offScreenWidth != srcRectWidthMag
|| offScreenHeight != srcRectHeightMag) {
offScreenImage = createImage(srcRectWidthMag, srcRectHeightMag);
offScreenWidth = srcRectWidthMag;
offScreenHeight = srcRectHeightMag;
}
Roi roi = imp.getRoi();
try {
if (imageUpdated) {
imageUpdated = false;
imp.updateImage();
}
Graphics offScreenGraphics = offScreenImage.getGraphics();
Java2.setBilinearInterpolation(offScreenGraphics, Prefs.interpolateScaledImages);
Image img = imp.getImage();
if (img != null)
offScreenGraphics.drawImage(
img,
0,
0,
srcRectWidthMag,
srcRectHeightMag,
srcRect.x,
srcRect.y,
srcRect.x + srcRect.width,
srcRect.y + srcRect.height,
null);
if (overlay != null) drawOverlay(offScreenGraphics);
if (showAllROIs) drawAllROIs(offScreenGraphics);
if (roi != null) drawRoi(roi, offScreenGraphics);
if (srcRect.width < imageWidth || srcRect.height < imageHeight)
drawZoomIndicator(offScreenGraphics);
if (IJ.debugMode) showFrameRate(offScreenGraphics);
g.drawImage(offScreenImage, 0, 0, null);
} catch (OutOfMemoryError e) {
IJ.outOfMemory("Paint");
}
}
public void paint(Graphics g) {
if (histogram != null) {
if (os == null) {
os = createImage(WIDTH, HEIGHT);
osg = os.getGraphics();
osg.setColor(Color.white);
osg.fillRect(0, 0, WIDTH, HEIGHT);
osg.setColor(Color.gray);
for (int i = 0; i < WIDTH; i++) {
if (hColors != null) osg.setColor(hColors[i]);
osg.drawLine(i, HEIGHT, i, HEIGHT - ((int) (HEIGHT * histogram[i]) / hmax) - 4);
}
osg.dispose();
}
g.drawImage(os, 0, 0, this);
} else {
g.setColor(Color.white);
g.fillRect(0, 0, WIDTH, HEIGHT);
}
g.setColor(Color.black);
g.drawLine(0, HEIGHT - 4, 256, HEIGHT - 4);
g.drawRect(0, 0, WIDTH, HEIGHT);
g.drawRect((int) minHue, 1, (int) (maxHue - minHue), HEIGHT - 5);
}