public override void MouseMove(CameraState state, Vector2 delta)
{
var mouse = Mouse.GetState();
if (mouse.IsButtonDown(MouseButton.Left))
{
HandleFreeLook(state, delta);
}
}
public override void UpdateFrame(CameraState state, float step)
{
base.UpdateFrame(state, step);
// update the up direction to always point away from the alignment point
var up = state.Position - AlignmentPoint;
up.Normalize();
// if the angle between the old and new up directions is larger than 90°
// we assume that the camera is upside down and keep it that way
state.Up = Vector3.Dot(state.Up, up) < 0 ? -up : up;
}
public override void MouseMove(CameraState state, Vector2 delta)
{
var mouse = Mouse.GetState();
if (mouse.IsButtonDown(MouseButton.Left))
{
base.MouseMove(state, delta);
var leftRight = Vector3.Cross(state.Up, state.LookAt);
Vector3.Cross(ref state.LookAt, ref leftRight, out state.Up);
state.Up.Normalize();
}
}
/// <summary>
/// TODO: add possibility to limit the pitch and prevent "flipping over"
/// </summary>
protected void HandleFreeLook(CameraState state, Vector2 delta)
{
var leftRight = Vector3.Cross(state.Up, state.LookAt);
var forward = Vector3.Cross(leftRight, state.Up);
// rotate look at direction
var rot = Matrix4.CreateFromAxisAngle(state.Up, -delta.X) * Matrix4.CreateFromAxisAngle(leftRight, delta.Y);
Vector3.Transform(ref state.LookAt, ref rot, out state.LookAt);
// renormalize to prevent summing up of floating point errors
state.LookAt.Normalize();
// flip up vector when pitched more than +/-90° from the forward direction
if (Vector3.Dot(state.LookAt, forward) < 0) state.Up *= -1;
}
public override void UpdateFrame(CameraState state, float step)
{
var keyboard = Keyboard.GetState();
var dir = Vector3.Zero;
var leftRight = Vector3.Cross(state.Up, state.LookAt).Normalized();
if (keyboard.IsKeyDown(Key.W)) dir += state.LookAt;
if (keyboard.IsKeyDown(Key.S)) dir -= state.LookAt;
if (keyboard.IsKeyDown(Key.A)) dir += leftRight;
if (keyboard.IsKeyDown(Key.D)) dir -= leftRight;
if (keyboard.IsKeyDown(Key.Space)) dir += state.Up;
if (keyboard.IsKeyDown(Key.LControl)) dir -= state.Up;
// normalize dir to enforce consistent movement speed, independent of the number of keys pressed
if (dir.LengthSquared > 0) state.Position += dir.Normalized() * step;
}
public override void MouseMove(CameraState state, Vector2 delta)
{
var mouse = Mouse.GetState();
if (mouse.IsButtonDown(MouseButton.Left))
{
// rotate look direction with mouse
HandleFreeLook(state, delta);
// recalculate the position
UpdateDistance(state, 0);
}
if (mouse.IsButtonDown(MouseButton.Right))
{
UpdateDistance(state, delta.Y);
}
}
public virtual void UpdateFrame(CameraState state, float step)
{
}
public virtual void MouseWheelChanged(CameraState state, float delta)
{
}
public virtual void MouseMove(CameraState state, Vector2 delta)
{
}
public virtual void Initialize(CameraState state)
{
}
public Camera()
{
State = new CameraState();
DefaultState = new CameraState();
}
protected void UpdateDistance(CameraState state, float scale)
{
state.Position = Origin - (state.Position - Origin).Length * (1 + scale) * state.LookAt;
}
public override void MouseWheelChanged(CameraState state, float delta)
{
if (delta > 100) delta = 100;
UpdateDistance(state, -delta);
}
public override void Initialize(CameraState state)
{
// recalculate look at direction
state.LookAt = Origin - state.Position;
state.LookAt.Normalize();
}
