public Camera(Vector3 position, Quaternion rotation, float aspectRatio, float fov)
{
_position = position;
_rotation = rotation.Normalized();
AspectRatio = aspectRatio;
FoV = fov;
}
public Mesh(Vector3[] vertices, Triangle[] triangles, Vector3 position, Quaternion rotation, Shader shader, ISampler normalSampler)
{
Vertices = vertices;
_triangles = triangles;
Shader = shader;
Position = position;
Rotation = rotation;
_normalSampler = normalSampler;
Init();
}
public static Quaternion LookRotation(Vector3 direction, Vector3 up)
{
Vector3 directionNormalized = direction.Normalized();
// Rotate around up vector
Vector3 directionProjected = (directionNormalized - up * Vector3.Dot(directionNormalized, up)).Normalized();
Vector3 forwardProjected = (Vector3.Forward - up * Vector3.Dot(Vector3.Forward, up)).Normalized();
float rotationAroundUpAngleHalf = (float) Math.Acos((Vector3.Dot(directionProjected, forwardProjected))) / 2;
var rotationAroundUp = new Quaternion(up * (float) Math.Sin(rotationAroundUpAngleHalf),
(float) Math.Cos(rotationAroundUpAngleHalf));
// Rotate around horizontal vector
Vector3 rotationAxis = Vector3.Cross(directionNormalized, directionProjected);
double angleHalf = Math.Acos(Vector3.Dot(directionNormalized, directionProjected)) / 2;
var rotationAroundHorizontal = new Quaternion(rotationAxis * (float) Math.Sin(angleHalf),
(float) Math.Cos(angleHalf));
return rotationAroundUp * rotationAroundHorizontal;
}
public Vector3 RotatedBy(Quaternion quaternion)
{
Vector3 t = 2 * Cross(quaternion.XYZ, this);
Vector3 rotated = this + quaternion.W * t + Cross(quaternion.XYZ, t);
return rotated;
}