MathUtil.java

package erebus.core.helper;

public final class MathUtil {
	private static final float F_D2R = 0.01745329251994327F;
	private static final float F_R2D = 57.2957795130823208F;
	private static final double D_D2R = 0.01745329251994327D;
	private static final double D_R2D = 57.2957795130823208D;

	public static float toRad(float deg) {
		return deg * F_D2R;
	}

	public static double toRad(double deg) {
		return deg * D_D2R;
	}

	public static float toDeg(float rad) {
		return rad * F_R2D;
	}

	public static double toDeg(double rad) {
		return rad * D_R2D;
	}

	public static float square(float n) {
		return n * n;
	}

	public static double square(double n) {
		return n * n;
	}

	public static double distance(double xDiff, double zDiff) {
		return Math.sqrt(xDiff * xDiff + zDiff * zDiff);
	}

	public static double distance(double xDiff, double yDiff, double zDiff) {
		return Math.sqrt(xDiff * xDiff + yDiff * yDiff + zDiff * zDiff);
	}

	public static boolean triangle(int xx, int yy, int x1, int y1, int x2, int y2, int x3, int y3) {
		int a0, a1, a2, a3;
		a0 = Math.abs((x2 - x1) * (y3 - y1) - (x3 - x1) * (y2 - y1));
		a1 = Math.abs((x1 - xx) * (y2 - yy) - (x2 - xx) * (y1 - yy));
		a2 = Math.abs((x2 - xx) * (y3 - yy) - (x3 - xx) * (y2 - yy));
		a3 = Math.abs((x3 - xx) * (y1 - yy) - (x1 - xx) * (y3 - yy));
		return Math.abs(a1 + a2 + a3 - a0) <= 1 / 256;
	}

	public static double lendirx(double len, double dir) {
		return Math.sin(Math.toRadians(dir)) * len;
	}

	public static double lendiry(double len, double dir) {
		return Math.cos(Math.toRadians(dir)) * len;
	}

	public static boolean floatEquals(float val1, float val2) {
		return Math.abs(val1 - val2) < 0.00001F;
	}

	private MathUtil() {
	}
}