public synchronized void paint(Graphics gin) {
Graphics2D g = (Graphics2D) gin;
if (im == null) return;
int height = getHeight();
int width = getWidth();
if (fit) {
t = new AffineTransform();
double scale = Math.min(((double) width) / im.getWidth(), ((double) height) / im.getHeight());
// we'll re-center the transform in a moment.
t.scale(scale, scale);
}
// if the image (in either X or Y) is smaller than the view port, then center
// the image with respect to that axis.
double mwidth = im.getWidth() * t.getScaleX();
double mheight = im.getHeight() * t.getScaleY();
if (mwidth < width)
t.preConcatenate(
AffineTransform.getTranslateInstance((width - mwidth) / 2.0 - t.getTranslateX(), 0));
if (mheight < height)
t.preConcatenate(
AffineTransform.getTranslateInstance(0, (height - mheight) / 2.0 - t.getTranslateY()));
// if we're allowing panning (because only a portion of the image is visible),
// don't allow translations that show less information that is possible.
Point2D topleft = t.transform(new Point2D.Double(0, 0), null);
Point2D bottomright = t.transform(new Point2D.Double(im.getWidth(), im.getHeight()), null);
if (mwidth > width) {
if (topleft.getX() > 0)
t.preConcatenate(AffineTransform.getTranslateInstance(-topleft.getX(), 0));
if (bottomright.getX() < width)
t.preConcatenate(AffineTransform.getTranslateInstance(width - bottomright.getX(), 0));
// t.translate(width-bottomright.getX(), 0);
}
if (mheight > height) {
if (topleft.getY() > 0)
t.preConcatenate(AffineTransform.getTranslateInstance(0, -topleft.getY()));
if (bottomright.getY() < height)
t.preConcatenate(AffineTransform.getTranslateInstance(0, height - bottomright.getY()));
}
g.drawImage(im, t, null);
}
// zoom out a notch
void zoomOut(Point2D p) {
double nz = t.getScaleX() * .5;
nz = Math.max(nz, 1.0 / 32.0);
adjustZoom(nz, p);
}
// zoom in a notch
void zoomIn(Point2D p) {
double nz = t.getScaleX() * 2.0;
nz = Math.min(nz, 64);
adjustZoom(nz, p);
}