/// <summary>
/// Smart collision detection allowing for pixel-perfect collisions.
/// </summary>
/// <param name="obj">Object to test against</param>
/// <returns></returns>
public override bool IsOverlappedWith(InteractableObject obj)
{
var box1 = GetBoundingBox(true);
var box2 = obj.GetBoundingBox(true);
var isect = Rectangle.Intersect(box1, box2);
if (isect.IsEmpty)
return false;
var gameObject = obj as GameObject;
// Check whether both objects are GameObjects and are neither rotated nor scaled
if (CollisionDetectionMode == CollisionDetectionMode.Fast
|| gameObject == null
|| !Scale.IsAlmost(1)
|| !obj.Scale.IsAlmost(1)
|| ScaleVector.HasValue
|| obj.ScaleVector.HasValue
|| (!Angle.IsAlmostNull() && CollisionDetectionMode != CollisionDetectionMode.Round)
|| (!gameObject.Angle.IsAlmostNull() && gameObject.CollisionDetectionMode != CollisionDetectionMode.Round)
)
return true;
// Convert it from screen coordinates to texture coordinates
Rectangle textureRect1 = isect, textureRect2 = isect;
textureRect1.X -= box1.X;
textureRect1.Y -= box1.Y;
textureRect2.X -= box2.X;
textureRect2.Y -= box2.Y;
var colorData1 = GetCurrentAnimation().GetTextureRegion(textureRect1);
var colorData2 = gameObject.GetCurrentAnimation().GetTextureRegion(textureRect2);
// If both pixels in the same location are non-transparent
// HACK: only 50% of the pixels are checked for the sake of speed
for (var idx = 0; idx < colorData1.Length; idx += 2)
if (colorData1[idx].A != 0 && colorData2[idx].A != 0)
return true;
return false;
}
/// <summary>
/// Check if a touch location has been handled.
/// </summary>
/// <param name="id">Touch id.</param>
/// <param name="obj">Object that has captured the touch.</param>
/// <returns></returns>
static public bool CanHandleTouch(int id, InteractableObject obj)
{
return !_RegisteredTouches.ContainsKey(id) || _RegisteredTouches[id] == obj;
}
/// <summary>
/// Check whether an object collides with another object.
/// Collision is rectangle based and non-rotatable.
/// </summary>
/// <param name="obj">Object to test collision to.</param>
public virtual bool IsOverlappedWith(InteractableObject obj)
{
return GetBoundingBox(true).Intersects(obj.GetBoundingBox(true));
}
/// <summary>
/// Register a touch location as handled.
/// </summary>
/// <param name="id">Touch location id.</param>
/// <param name="obj">Object to capture the touch.</param>
static public void HandleTouch(int id, InteractableObject obj)
{
if(!_RegisteredTouches.ContainsKey(id))
_RegisteredTouches.Add(id, obj);
}