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manderin87

Member Since 20 Feb 2005
Offline Last Active Dec 14 2012 10:38 PM
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Posts I've Made

In Topic: Polygon rotation is too fast compared to objects rotation

30 November 2012 - 01:11 PM

Ive rechecked everything... The rotation code was the problem.... I made two lists to keep track of the points... the original points and the rotated points. Both were pointing to the same object, i thought they were seperate, but they were not... so I just made both lists create a new point when adding to the list. The rotation is now correct.

Here is the polygon constructor

public Polygon(Point... points) {
  if(points.length < 3) {
   throw new IllegalArgumentException("polygons must contain at least 3 points.");
  }

  for(Point p : points) {
   mRotatedPoints.add(new Point(p));
   mOriginalPoints.add(new Point(p));
  }
}

And the rotation code.

public void rotate(float x0, float y0, float degree) {
  for(int i = 0; i < mOriginalPoints.size(); i++) {
   Point point = mOriginalPoints.get(i);
  
   float x = (float) (x0 + (point.x - x0) * Math.cos(Utilities.toRadians(degree)) -
				  (point.y - y0) * Math.sin(Utilities.toRadians(degree)));
   float y = (float) (y0 + (point.x - x0) * Math.sin(Utilities.toRadians(degree)) +
			(point.y - y0) * Math.cos(Utilities.toRadians(degree)));

   Point p = mRotatedPoints.get(i);
   p.x = x;
   p.y = y;
  }

thanks everyone for the help and forgive my idiocy for not noticing they were they same instead of being seperate.

In Topic: Polygon rotation is too fast compared to objects rotation

29 November 2012 - 09:11 PM

while(mDegree >= 360) {mDegree -= 360;}
while(mDegree < 0) {mDegree += 360;}


Didnt fix it. I know it has to be something wrong with the polygone rotation, its not working correctly. Ive stared at it for hours and i dont know what the problem is. Ive checked several places and the algorithm seems to be correct, but its not rotating correctly.

In Topic: Polygon rotation is too fast compared to objects rotation

29 November 2012 - 09:04 PM

Does SpriteBatch::draw() want degrees or radians?


Degrees

In Topic: Polygon rotation is too fast compared to objects rotation

29 November 2012 - 06:38 PM

Its the same thing... my Utilities.toRadians() calls Math.toRadians()

In Topic: Polygon rotation is too fast compared to objects rotation

29 November 2012 - 05:34 PM

This method is better for fixing the degree but it didnt change the behavior that I am experiencing

if(mDegree >= 360) {
   mDegree -= 360;
  } else if(mDegree < 0) {
   mDegree += 360;
  }

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