public void Update(int X, int Y)
{
phi = -rotateScale * X + (float)Math.PI;
theta = rotateScale * Y + 0.5f * (float)Math.PI;
if (theta <= 0.00001f)
{
theta = 0.00001f;
Y = -(int)((0.5f * Math.PI) / rotateScale);
}
else if (theta >= Math.PI)
{
theta = (float)Math.PI;
Y = (int)((0.5f * (float)Math.PI) / rotateScale);
}
forward = new Vec3((float)(Math.Sin(theta) * Math.Sin(phi)), (float)(Math.Cos(theta)), (float)(Math.Sin(theta) * Math.Cos(phi)));
forward.normalize();
right = new Vec3(Vec3.cross(new Vec3(forward.x, 0, forward.z), forward));
right.normalize();
Quaternion rotationPhi = new Quaternion(new Vec3(0.0f, 1.0f, 0.0f), phi);
float axisTheta = phi + 0.5f * (float)Math.PI;
Vec3 rotateThetaAxis = new Vec3((float)Math.Sin(axisTheta), 0.0f, (float)Math.Cos(axisTheta));
Quaternion rotationTheta = new Quaternion(rotateThetaAxis, theta);
rotation = rotationTheta * rotationPhi;
}
public static Transform rotate(Vec3 axis, float degree)
{
axis.normalize();
Mat4 m1 = new Mat4();
float cosa = (float)Math.Cos(degree);
float sina = (float)-Math.Sin(degree);
float ncosa = 1 - cosa;
float xy = axis.x * axis.y;
float xz = axis.x * axis.z;
float yz = axis.y * axis.z;
m1[0, 0] = cosa + (axis.x * axis.x) * ncosa;
m1[0, 1] = xy * ncosa - axis.z * sina;
m1[0, 2] = xz * ncosa + axis.y * sina;
m1[0, 3] = 0;
m1[1, 0] = xy * ncosa + axis.z * sina;
m1[1, 1] = cosa + axis.y * axis.y * ncosa;
m1[1, 2] = yz * ncosa - axis.x * sina;
m1[1, 3] = 0;
m1[2, 0] = xz * ncosa - axis.y * sina;
m1[2, 1] = yz * ncosa + axis.x * sina;
m1[2, 2] = axis.z * axis.z * ncosa + cosa;
m1[2, 3] = 0;
m1[3, 0] = 0;
m1[3, 1] = 0;
m1[3, 2] = 0;
m1[3, 3] = 1;
return(new Transform(m1));
}
public Quaternion(Vec3 axis, float theta)
{
axis.normalize();
imaginaryPart = (float)Math.Sin(0.5f * theta) * axis;
realPart = (float)Math.Cos(0.5f * theta);
}