internal static Vector3 Do(int id, Vector3 position, Vector3 offset, Vector3 handleDirection, Vector3 slideDirection, float size, Handles.CapFunction capFunction, float snap)
{
Event evt = Event.current;
var eventType = evt.GetTypeForControl(id);
switch (eventType)
{
case EventType.Layout:
case EventType.MouseMove:
if (capFunction != null)
{
capFunction(id, position + offset, Quaternion.LookRotation(handleDirection), size, eventType);
}
else
{
HandleUtility.AddControl(id, HandleUtility.DistanceToCircle(position + offset, size * .2f));
}
break;
case EventType.MouseDown:
// am I closest to the thingy?
if (HandleUtility.nearestControl == id && evt.button == 0 && GUIUtility.hotControl == 0 && !evt.alt)
{
GUIUtility.hotControl = id; // Grab mouse focus
s_StartMousePosition = evt.mousePosition;
s_ConstraintOrigin = Handles.matrix.MultiplyPoint3x4(position);
s_StartPosition = position;
s_ConstraintDirection = Handles.matrix.MultiplyVector(slideDirection);
s_HandleOffset = HandleUtility.CalcPositionOnConstraint(Camera.current, evt.mousePosition, s_ConstraintOrigin, s_ConstraintDirection, out Vector3 point)
? s_ConstraintOrigin - point
: Vector3.zero;
evt.Use();
s_StartHandleSize = HandleUtility.GetHandleSize(point);
}
break;
case EventType.MouseDrag:
if (GUIUtility.hotControl == id)
{
// First try to calculate the translation by casting a mouse ray against a world position plane
// oriented towards the camera. This gives more accurate results than doing the line translation
// in 2D space, but is more prone towards skewing extreme values when the ray is near parallel
// to the plane. To address this, CalcPositionOnConstraint will fail if the mouse ray is close
// to parallel (see HandleUtility.k_MinRayConstraintDot) and fall back to 2D based movement.
if (HandleUtility.CalcPositionOnConstraint(Camera.current, evt.mousePosition, s_ConstraintOrigin, s_ConstraintDirection, out Vector3 worldPosition))
{
var handleOffset = s_HandleOffset * (HandleUtility.GetHandleSize(worldPosition) / s_StartHandleSize);
worldPosition += handleOffset;
if (EditorSnapSettings.incrementalSnapActive)
{
Vector3 dir = worldPosition - s_ConstraintOrigin;
float dist = Handles.SnapValue(dir.magnitude, snap) * Mathf.Sign(Vector3.Dot(s_ConstraintDirection, dir));
worldPosition = s_ConstraintOrigin + s_ConstraintDirection.normalized * dist;
}
else if (EditorSnapSettings.gridSnapActive)
{
worldPosition = Snapping.Snap(worldPosition, GridSettings.size, (SnapAxis) new SnapAxisFilter(s_ConstraintDirection));
}
position = Handles.inverseMatrix.MultiplyPoint(worldPosition);
s_StartPosition = position;
s_StartMousePosition = evt.mousePosition;
}
else
{
// Unlike HandleUtility.CalcPositionOnConstraint, CalcLineTranslation _does_ multiply constraint
// origin and direction by Handles.matrix, so make sure to pass in unmodified vectors here
float dist = HandleUtility.CalcLineTranslation(s_StartMousePosition, evt.mousePosition, s_StartPosition, slideDirection);
dist = Handles.SnapValue(dist, snap);
worldPosition = Handles.matrix.MultiplyPoint(s_StartPosition) + s_ConstraintDirection * dist;
if (EditorSnapSettings.gridSnapActive)
{
worldPosition = Snapping.Snap(worldPosition, GridSettings.size, (SnapAxis) new SnapAxisFilter(s_ConstraintDirection));
}
position = Handles.inverseMatrix.MultiplyPoint(worldPosition);
}
GUI.changed = true;
evt.Use();
}
break;
case EventType.MouseUp:
if (GUIUtility.hotControl == id && (evt.button == 0 || evt.button == 2))
{
GUIUtility.hotControl = 0;
evt.Use();
}
break;
case EventType.Repaint:
Color temp = Color.white;
if (id == GUIUtility.hotControl)
{
temp = Handles.color;
Handles.color = Handles.selectedColor;
}
else if (id == HandleUtility.nearestControl && GUIUtility.hotControl == 0 && !evt.alt)
{
temp = Handles.color;
Handles.color = Handles.preselectionColor;
}
capFunction(id, position + offset, Quaternion.LookRotation(handleDirection), size, EventType.Repaint);
if (id == GUIUtility.hotControl || id == HandleUtility.nearestControl && GUIUtility.hotControl == 0)
{
Handles.color = temp;
}
break;
}
return(position);
}