// 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) {
Roi roi = imp.getRoi();
if (roi != null || showAllROIs || overlay != null) {
if (roi != null) roi.updatePaste();
if (!IJ.isMacOSX() && imageWidth != 0) {
paintDoubleBuffered(g);
return;
}
}
try {
if (imageUpdated) {
imageUpdated = false;
imp.updateImage();
}
Java2.setBilinearInterpolation(g, Prefs.interpolateScaledImages);
Image img = imp.getImage();
if (img != null)
g.drawImage(
img,
0,
0,
(int) (srcRect.width * magnification),
(int) (srcRect.height * magnification),
srcRect.x,
srcRect.y,
srcRect.x + srcRect.width,
srcRect.y + srcRect.height,
null);
if (overlay != null) drawOverlay(g);
if (showAllROIs) drawAllROIs(g);
if (roi != null) drawRoi(roi, g);
if (srcRect.width < imageWidth || srcRect.height < imageHeight) drawZoomIndicator(g);
if (IJ.debugMode) showFrameRate(g);
} catch (OutOfMemoryError e) {
IJ.outOfMemory("Paint");
}
}