public void rotate(float x0, float y0, double angle) {
Log.i("Polygon", "Degree: " + angle);
for(int i = 0; i < mPoints.size(); i++) {
Point point = mPoints.get(i);
float x = (float) (x0 + (point.x - x0) * Math.cos(Utilities.toRadians(angle)) -
(point.y - y0) * Math.sin(Utilities.toRadians(angle)));
float y = (float) (y0 + (point.x - x0) * Math.sin(Utilities.toRadians(angle)) +
(point.y - y0) * Math.cos(Utilities.toRadians(angle)));
point.x = x;
point.y = y;
}
}
The sprite rotation is done through a libgdx spritebatch and I am certain its correct.
public void draw(SpriteBatch batch, float x, float y, float degree) {
batch.draw(mImage, x - width() / 2, y - height() / 2,
pivotX(), pivotY(),
width(), height(),
mScale, mScale,
degree,
0, 0,
(int) width(), (int) height(),
false, false);
}
The delta time comes from libgdx and is the time since last frame.
float deltaTime = Gdx.graphics.getDeltaTime();
I am almost certain its something in the polygon rotation code... I was testing it... it would rotate until a certain point and then go the other way.