computeAngle.java

//declarations
		int above = 0;
		int below = 0;
		double inverseSlope = -1/slope;
		
		//for each pixel, check if above or below slope perpendicular
		for (int i = 0; i < connectedPixels.length; ++i) {
			for (int j = 0; j < connectedPixels[0].length; ++j) {
				
				int x = j - col;
				int y = row - i;
				
				if ( y >= inverseSlope*x && connectedPixels[i][j] == true && i != row && j != col) {
					++above;
				} else if ( y < inverseSlope*x && connectedPixels[i][j] == true && i != row && j != col) {
					++below;
				}
			}
		}
		
		//calculate initial angle
		double angle = Math.atan(slope);
		
		//refine angle
		if ((angle > 0 && below>above) || (angle < 0 && below < above) ) {
			angle += Math.PI;
		} else if (slope == Double.POSITIVE_INFINITY && above>below) {
			angle = Math.PI/2;
		} else if (slope == Double.POSITIVE_INFINITY && above<below) {
			angle = -Math.PI/2;
		}
		
		return angle;
	}