public Number3D lerp(Number3D from, Number3D to, float amount) {
Number3D out = new Number3D();
out.x = from.x + (to.x - from.x) * amount;
out.y = from.y + (to.y - from.y) * amount;
out.z = from.z + (to.z - from.z) * amount;
return out;
}
public Number3D cross(Number3D w) {
_temp.setAllFrom(this);
x = w.y * _temp.z - w.z * _temp.y;
y = w.z * _temp.x - w.x * _temp.z;
z = w.x * _temp.y - w.y * _temp.x;
return this;
}
public static Number3D getAxisVector(Axis axis) {
Number3D axisVector = new Number3D();
switch (axis) {
case X:
axisVector.setAll(1, 0, 0);
break;
case Y:
axisVector.setAll(0, 1, 0);
break;
case Z:
axisVector.setAll(0, 0, 1);
break;
}
return axisVector;
}
public void rotateZ(float angle) {
float cosRY = FloatMath.cos(angle);
float sinRY = FloatMath.sin(angle);
_temp.setAll(this.x, this.y, this.z);
this.x = (_temp.x * cosRY) - (_temp.y * sinRY);
this.y = (_temp.x * sinRY) + (_temp.y * cosRY);
}
/**
* http://ogre.sourcearchive.com/documentation/1.4.5/classOgre_1_1Vector3_eeef4472ad0c4d5f34a038a9f2faa819.html#eeef4472ad0c4d5f34a038a9f2faa819
*
* @param direction
* @return
*/
public Quaternion getRotationTo(Number3D direction) {
// Based on Stan Melax's article in Game Programming Gems
Quaternion q = new Quaternion();
// Copy, since cannot modify local
Number3D v0 = this;
Number3D v1 = direction;
v0.normalize();
v1.normalize();
float d = Number3D.dot(v0, v1);
// If dot == 1, vectors are the same
if (d >= 1.0f) {
q.setIdentity();
}
if (d < 0.000001f - 1.0f) {
// Generate an axis
Number3D axis = Number3D.cross(Number3D.getAxisVector(Axis.X), this);
if (axis.length() == 0) // pick another if colinear
axis = Number3D.cross(Number3D.getAxisVector(Axis.Y), this);
axis.normalize();
q.fromAngleAxis(MathUtil.radiansToDegrees(MathUtil.PI), axis);
} else {
float s = FloatMath.sqrt((1 + d) * 2);
float invs = 1f / s;
Number3D c = Number3D.cross(v0, v1);
q.x = c.x * invs;
q.y = c.y * invs;
q.z = c.z * invs;
q.w = s * 0.5f;
q.normalize();
}
return q;
}