private static bool ConstructPlaneIntersection(Vector3 Position, Matrix4x4 viewProjection, Ray ray, Vector3 perpendicularVector0, Vector3 perpendicularVector1, out Vector3 intersection)
{
// Choose the perpendicular plane that is more parallel to the camera plane to
// maximize the available accuracy in the view space.
Vector3 viewDirection = new Vector3(viewProjection.M31, viewProjection.M32, viewProjection.M33);
float perpendicularVector0Dot = Math.Abs(Vector3.Dot(viewDirection, perpendicularVector0));
float perpendicularVector1Dot = Math.Abs(Vector3.Dot(viewDirection, perpendicularVector1));
Plane plane = MathC.CreatePlaneAtPoint(Position, perpendicularVector0Dot > perpendicularVector1Dot ? perpendicularVector0 : perpendicularVector1);
// Construct intersection
return(Collision.RayIntersectsPlane(ray, plane, out intersection));
}
public PickingResultGizmo DoPicking(Ray ray)
{
if (!DrawGizmo)
{
return(null);
}
bool upside = Orientation == GizmoOrientation.UpsideDown;
// Check for translation
if (SupportTranslateX)
{
float unused;
BoundingSphere sphereX = new BoundingSphere(Position + Vector3.UnitX * (upside ? -Size : Size) * _arrowHeadOffsetMultiplier, TranslationConeSize / 1.5f);
if (Collision.RayIntersectsSphere(ray, sphereX, out unused))
{
return(new PickingResultGizmo(GizmoMode.TranslateX));
}
}
if (SupportTranslateY)
{
float unused;
BoundingSphere sphereY = new BoundingSphere(Position + Vector3.UnitY * (upside ? -Size : Size) * _arrowHeadOffsetMultiplier, TranslationConeSize / 1.5f);
if (Collision.RayIntersectsSphere(ray, sphereY, out unused))
{
return(new PickingResultGizmo(GizmoMode.TranslateY));
}
}
if (SupportTranslateZ)
{
float unused;
BoundingSphere sphereZ = new BoundingSphere(Position - Vector3.UnitZ * (upside ? -Size : Size) * _arrowHeadOffsetMultiplier, TranslationConeSize / 1.5f);
if (Collision.RayIntersectsSphere(ray, sphereZ, out unused))
{
return(new PickingResultGizmo(GizmoMode.TranslateZ));
}
}
// Check for scale
if (SupportScale)
{
float unused;
BoundingBox scaleX = new BoundingBox(Position + Vector3.UnitX * (upside ? -Size : Size) / 2.0f - new Vector3(ScaleCubeSize / 2.0f),
Position + Vector3.UnitX * (upside ? -Size : Size) / 2.0f + new Vector3(ScaleCubeSize / 2.0f));
if (Collision.RayIntersectsBox(ray, scaleX, out unused))
{
return(new PickingResultGizmo(GizmoMode.ScaleX));
}
BoundingBox scaleY = new BoundingBox(Position + Vector3.UnitY * (upside ? -Size : Size) / 2.0f - new Vector3(ScaleCubeSize / 2.0f),
Position + Vector3.UnitY * (upside ? -Size : Size) / 2.0f + new Vector3(ScaleCubeSize / 2.0f));
if (Collision.RayIntersectsBox(ray, scaleY, out unused))
{
return(new PickingResultGizmo(GizmoMode.ScaleY));
}
BoundingBox scaleZ = new BoundingBox(Position - Vector3.UnitZ * (upside ? -Size : Size) / 2.0f - new Vector3(ScaleCubeSize / 2.0f),
Position - Vector3.UnitZ * (upside ? -Size : Size) / 2.0f + new Vector3(ScaleCubeSize / 2.0f));
if (Collision.RayIntersectsBox(ray, scaleZ, out unused))
{
return(new PickingResultGizmo(GizmoMode.ScaleZ));
}
}
// Check for rotation
float pickRadius = LineThickness / 2 + (Size * 0.045f);
if (SupportRotationZ)
{
Plane planeZ = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitZ, RotateMatrixZ));
Vector3 intersectionPoint;
if (Collision.RayIntersectsPlane(ray, planeZ, out intersectionPoint))
{
var distance = (intersectionPoint - Position).Length();
if (distance >= Size - pickRadius && distance <= Size + pickRadius)
{
Vector3 startDirection = Vector3.Normalize(intersectionPoint - Position);
float sin = Vector3.Dot(Vector3.UnitY, startDirection);
float cos = Vector3.Dot(planeZ.Normal, Vector3.Cross(Vector3.UnitY, startDirection));
return(new PickingResultGizmo(GizmoMode.RotateZ, (float)Math.Atan2(-sin, cos), distance));
}
}
}
if (SupportRotationX)
{
Plane planeX = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitX, RotateMatrixX));
Vector3 intersectionPoint;
if (Collision.RayIntersectsPlane(ray, planeX, out intersectionPoint))
{
var distance = (intersectionPoint - Position).Length();
if (distance >= Size - pickRadius && distance <= Size + pickRadius)
{
Vector3 startDirection = Vector3.Normalize(intersectionPoint - Position);
float sin = Vector3.Dot(Vector3.UnitY, startDirection);
float cos = Vector3.Dot(planeX.Normal, Vector3.Cross(Vector3.UnitY, startDirection));
return(new PickingResultGizmo(GizmoMode.RotateX, (float)Math.Atan2(-sin, cos), distance));
}
}
}
if (SupportRotationY)
{
Plane planeY = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitY, RotateMatrixY));
Vector3 intersectionPoint;
if (Collision.RayIntersectsPlane(ray, planeY, out intersectionPoint))
{
var distance = (intersectionPoint - Position).Length();
if (distance >= Size - pickRadius && distance <= Size + pickRadius)
{
Vector3 startDirection = Vector3.Normalize(intersectionPoint - Position);
float sin = Vector3.Dot(Vector3.UnitZ, startDirection);
float cos = Vector3.Dot(planeY.Normal, Vector3.Cross(Vector3.UnitZ, startDirection));
return(new PickingResultGizmo(GizmoMode.RotateY, (float)Math.Atan2(-sin, cos), distance));
}
}
}
return(null);
}
/// <returns>true, if an iteraction with the gizmo is happening</returns>
public bool MouseMoved(Matrix4x4 viewProjection, Ray ray)
{
if (!DrawGizmo || _mode == GizmoMode.None)
{
return(false);
}
bool upside = Orientation == GizmoOrientation.UpsideDown;
bool flippedScale = false;
// Flip sizing dimensions if object is rotateable on Y axis
if ((_mode == GizmoMode.ScaleX || _mode == GizmoMode.ScaleZ) && SupportRotationY)
{
flippedScale = MathC.RadToDeg(RotationY) % 180.0f >= 45.0f;
}
// First get the ray in 3D space from X, Y mouse coordinates
switch (_mode)
{
case GizmoMode.TranslateX:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitY, Vector3.UnitZ, out intersection))
{
GizmoMove(new Vector3(intersection.X - (upside ? -Size : Size) * _arrowHeadOffsetMultiplier, Position.Y, Position.Z));
GizmoMoveDelta(new Vector3(intersection.X - (upside ? -Size : Size) * _arrowHeadOffsetMultiplier - Position.X, 0.0f, 0.0f));
}
}
break;
case GizmoMode.TranslateY:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitX, Vector3.UnitZ, out intersection))
{
GizmoMove(new Vector3(Position.X, intersection.Y - (upside ? -Size : Size) * _arrowHeadOffsetMultiplier, Position.Z));
GizmoMoveDelta(new Vector3(0.0f, intersection.Y - (upside ? -Size : Size) * _arrowHeadOffsetMultiplier - Position.Y, 0.0f));
}
}
break;
case GizmoMode.TranslateZ:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitX, Vector3.UnitY, out intersection))
{
GizmoMove(new Vector3(Position.X, Position.Y, intersection.Z + (upside ? -Size : Size) * _arrowHeadOffsetMultiplier));
GizmoMoveDelta(new Vector3(0.0f, 0.0f, intersection.Z + (upside ? -Size : Size) * _arrowHeadOffsetMultiplier - Position.Z));
}
}
break;
case GizmoMode.ScaleX:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitY, Vector3.UnitZ, out intersection))
{
if (flippedScale)
{
GizmoScaleZ(_scaleBase.Z * (float)Math.Exp(_scaleSpeed * (intersection.X - Position.X)));
}
else
{
GizmoScaleX(_scaleBase.X * (float)Math.Exp(_scaleSpeed * (intersection.X - Position.X)));
}
}
}
break;
case GizmoMode.ScaleY:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitX, Vector3.UnitZ, out intersection))
{
GizmoScaleY(_scaleBase.Y * (float)Math.Exp(_scaleSpeed * (intersection.Y - Position.Y)));
}
}
break;
case GizmoMode.ScaleZ:
{
Vector3 intersection;
if (ConstructPlaneIntersection(Position, viewProjection, ray, Vector3.UnitX, Vector3.UnitY, out intersection))
{
if (flippedScale)
{
GizmoScaleX(_scaleBase.X * (float)Math.Exp(_scaleSpeed * -(intersection.Z - Position.Z)));
}
else
{
GizmoScaleZ(_scaleBase.Z * (float)Math.Exp(_scaleSpeed * -(intersection.Z - Position.Z)));
}
}
}
break;
case GizmoMode.RotateY:
{
Plane rotationPlane = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitY, RotateMatrixY));
Vector3 rotationIntersection;
if (Collision.RayIntersectsPlane(ray, rotationPlane, out rotationIntersection))
{
Vector3 direction = rotationIntersection - Position;
_rotationLastMouseRadius = direction.Length();
direction = Vector3.Normalize(direction);
float sin = Vector3.Dot(Vector3.UnitZ, direction);
float cos = Vector3.Dot(rotationPlane.Normal, Vector3.Cross(Vector3.UnitZ, direction));
_rotationLastMouseAngle = (float)Math.Atan2(-sin, cos);
GizmoRotateY(SimplifyAngle(_rotationPickAngleOffset + _rotationLastMouseAngle));
}
}
break;
case GizmoMode.RotateX:
{
Plane rotationPlane = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitX, RotateMatrixX));
Vector3 rotationIntersection;
if (Collision.RayIntersectsPlane(ray, rotationPlane, out rotationIntersection))
{
Vector3 direction = rotationIntersection - Position;
_rotationLastMouseRadius = direction.Length();
direction = Vector3.Normalize(direction);
float sin = Vector3.Dot(Vector3.UnitY, direction);
float cos = Vector3.Dot(rotationPlane.Normal, Vector3.Cross(Vector3.UnitY, direction));
_rotationLastMouseAngle = (float)Math.Atan2(-sin, cos);
GizmoRotateX(SimplifyAngle(_rotationPickAngleOffset + _rotationLastMouseAngle));
}
}
break;
case GizmoMode.RotateZ:
{
Plane rotationPlane = MathC.CreatePlaneAtPoint(Position, MathC.HomogenousTransform(Vector3.UnitZ, RotateMatrixZ));
Vector3 rotationIntersection;
if (Collision.RayIntersectsPlane(ray, rotationPlane, out rotationIntersection))
{
Vector3 direction = rotationIntersection - Position;
_rotationLastMouseRadius = direction.Length();
direction = Vector3.Normalize(direction);
float sin = Vector3.Dot(Vector3.UnitY, direction);
float cos = Vector3.Dot(rotationPlane.Normal, Vector3.Cross(Vector3.UnitY, direction));
_rotationLastMouseAngle = (float)Math.Atan2(-sin, cos);
GizmoRotateZ(SimplifyAngle(_rotationPickAngleOffset + _rotationLastMouseAngle));
}
}
break;
}
return(true);
}