@Override
protected void transformInverse(int x, int y, float[] out) {
float dx = x - icentreX;
float dy = y - icentreY;
float distance = dx * dx + dy * dy;
if (distance > radius2 || distance == 0) {
// out[0] = x;
// out[1] = y;
double angle = FastMath.atan2(dy, dx);
angle += rotateResultAngle;
double r = Math.sqrt(distance);
double zoomedR = r / zoom;
float u = (float) (zoomedR * FastMath.cos(angle));
float v = (float) (zoomedR * FastMath.sin(angle));
out[0] = (u + icentreX);
out[1] = (v + icentreY);
} else {
float scaledDist = (float) Math.sqrt(distance / radius2);
float pinchBulgeFactor =
(float) FastMath.pow(FastMath.sin(Math.PI * 0.5 * scaledDist), -pinchBulgeAmount);
// pinch-bulge
dx *= pinchBulgeFactor;
dy *= pinchBulgeFactor;
// twirl
float e = 1 - scaledDist;
float a = angle * e * e;
a += rotateResultAngle;
float sin = (float) FastMath.sin(a);
float cos = (float) FastMath.cos(a);
float u = (cos * dx - sin * dy) / zoom;
float v = (sin * dx + cos * dy) / zoom;
out[0] = icentreX + u;
out[1] = icentreY + v;
}
}
