private void init(final Content c, final int x, final int y) {
xLast = x;
yLast = y;
content = c;
// some transforms
c.getLocalToVworld(localToVWorld);
localToVWorldInverse.invert(localToVWorld);
canvas.getImagePlateToVworld(ipToVWorld);
ipToVWorldInverse.invert(ipToVWorld);
// calculate the canvas position in world coords
c.getContent().getCenter(centerInVWorld);
localToVWorld.transform(centerInVWorld);
ipToVWorldInverse.transform(centerInVWorld, centerInIp);
// get the eye point in world coordinates
canvas.getCenterEyeInImagePlate(eyePtInVWorld);
ipToVWorld.transform(eyePtInVWorld);
// use picking to infer the radius of the virtual sphere which is rotated
final Point3d p = univ.getPicker().getPickPointGeometry(c, x, y);
float r = 0, dD = 0;
if (p != null) {
pickPtInVWorld.set(p);
localToVWorld.transform(pickPtInVWorld);
r = (float) pickPtInVWorld.distance(centerInVWorld);
} else {
c.getContent().getMin(p1);
localToVWorld.transform(p1);
r = (float) p1.distance(centerInVWorld);
vec.sub(centerInVWorld, eyePtInVWorld);
vec.normalize();
vec.scale(-r);
pickPtInVWorld.add(centerInVWorld, vec);
}
dD = (float) pickPtInVWorld.distance(eyePtInVWorld);
// calculate distance between eye and canvas point
canvas.getPixelLocationInImagePlate(x, y, p1);
ipToVWorld.transform(p1);
final float dd = (float) p1.distance(eyePtInVWorld);
// calculate the virtual distance between two neighboring pixels
canvas.getPixelLocationInImagePlate(x + 1, y, p2);
ipToVWorld.transform(p2);
final float dx = (float) p1.distance(p2);
// calculate the virtual distance between two neighboring pixels
canvas.getPixelLocationInImagePlate(x, y + 1, p3);
ipToVWorld.transform(p3);
final float dy = (float) p1.distance(p3);
final float dX = dD / dd * dx;
final float dY = dD / dd * dy;
anglePerPix = Math.atan2(dX, r);
univ.getViewPlatformTransformer().getYDir(axisPerDx, ipToVWorld);
univ.getViewPlatformTransformer().getXDir(axisPerDy, ipToVWorld);
translationPerDx.set(axisPerDy);
translationPerDx.scale(dX);
translationPerDy.set(axisPerDx);
translationPerDy.scale(dY);
rotateTG = c.getLocalRotate();
translateTG = c.getLocalTranslate();
c.getContent().getCenter(vec);
transl_inv.set(vec);
vec.set(-vec.x, -vec.y, -vec.z);
transl.set(vec);
}
