/// <summary>
///
/// </summary>
/// <param name="sphere"></param>
/// <param name="hitGeom"></param>
/// <param name="collisionGroup"></param>
/// <returns></returns>
public bool SphereCast(gxtSphere sphere, out gxtGeom hitGeom, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL)
{
hitGeom = null;
List<gxtGeom> geoms;
if (SphereCastAll(sphere, out geoms, collisionGroup))
{
float minDist = float.MaxValue;
float tmpDist;
for (int i = 0; i < geoms.Count; i++)
{
tmpDist = (sphere.Position - geoms[i].GetWorldCentroid()).LengthSquared();
if (tmpDist < minDist)
{
hitGeom = geoms[i];
minDist = tmpDist;
}
}
return true;
}
return false;
}
/// <summary>
///
/// </summary>
/// <param name="sphere"></param>
/// <param name="hitGeoms"></param>
/// <param name="collisionGroup"></param>
/// <returns></returns>
public bool SphereCastAll(gxtSphere sphere, out List<gxtGeom> hitGeoms, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL)
{
if (collisionGroup == gxtCollisionGroup.NONE)
{
hitGeoms = new List<gxtGeom>();
return false;
}
// we pass an aabb of the sphere thru the broadphase collider...for now
// narrowphase tests use the actual sphere
gxtAABB aabb = new gxtAABB(sphere.Position, new Vector2(sphere.Radius));
hitGeoms = broadphaseCollider.AABBCastAll(aabb);
if (hitGeoms.Count == 0)
return false;
gxtPolygon geomPolygon;
for (int i = hitGeoms.Count - 1; i >= 0; i--)
{
if (!CanCollide(collisionGroup, hitGeoms[i]))
hitGeoms.RemoveAt(i);
else
{
geomPolygon = hitGeoms[i].Polygon;
// must ue the guranteed world centroid to ensure an accurate test
// http://www.gamedev.net/topic/308060-circle-polygon-intersection-more-2d-collisions/
if (!gxtGJKCollider.Intersects(ref geomPolygon, hitGeoms[i].GetWorldCentroid(), sphere))
hitGeoms.RemoveAt(i);
}
}
return hitGeoms.Count != 0;
}
/// <summary>
/// Casts a ray into the world with the given max distance and collision filter
/// Packages the nearest hit object and information on the ray cast into the rayHit structure
/// Returns true if an object is intersected by the ray, false otherwise
/// </summary>
/// <param name="ray">Ray</param>
/// <param name="rayHit">Ray Hit</param>
/// <param name="tmax">Max Ray Distance</param>
/// <param name="collisionGroup">Collision Groups</param>
/// <returns>If an object was hit</returns>
public bool RayCast(gxtRay ray, out gxtRayHit rayHit, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL, float tmax = float.MaxValue)
{
rayHit = new gxtRayHit();
if (collisionGroup == gxtCollisionGroup.NONE)
return false;
List<gxtGeom> geoms = broadphaseCollider.RayCastAll(ray, tmax, true);
if (geoms.Count == 0)
return false;
float t;
float minDist = tmax;
Vector2 pt, normal;
for (int i = 0; i < geoms.Count; i++)
{
if (CanCollide(collisionGroup, geoms[i]))
{
if (gxtGJKCollider.RayCast(ray, geoms[i].Polygon, tmax, out t, out pt, out normal))
{
if (t <= minDist)
{
rayHit.Intersection = true;
rayHit.Distance = t;
rayHit.Normal = normal;
rayHit.Point = pt;
rayHit.Geom = geoms[i];
minDist = t;
}
}
}
}
return rayHit.Intersection;
}
/// <summary>
/// Similar to RayCast() but all intersections, not just the nearest one, is processed and
/// added to the passed in list of ray hits. Said list is not sorted by distance. If you
/// require a sorted list you must do this yourself in the calling function.
/// Returns true if at least one geom is intersected.
/// </summary>
/// <param name="ray">Ray</param>
/// <param name="rayHits">List of Ray Hits</param>
/// <param name="collisionGroup">Collision Group</param>
/// <param name="tmax">Max Ray Distance</param>
/// <returns>If any geoms are intersected</returns>
public bool RayCastAll(gxtRay ray, out List<gxtRayHit> rayHits, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL, float tmax = float.MaxValue)
{
rayHits = new List<gxtRayHit>();
if (collisionGroup == gxtCollisionGroup.NONE)
return false;
List<gxtGeom> geoms = broadphaseCollider.RayCastAll(ray, tmax);
if (geoms.Count == 0)
return false;
// variables in ray hit
float t;
Vector2 pt, normal;
for (int i = 0; i < geoms.Count; i++)
{
if (CanCollide(collisionGroup, geoms[i]))
{
if (gxtGJKCollider.RayCast(ray, geoms[i].Polygon, tmax, out t, out pt, out normal))
{
gxtRayHit rayHit = new gxtRayHit();
rayHit.Intersection = true;
rayHit.Distance = t;
rayHit.Normal = normal;
rayHit.Point = pt;
rayHit.Geom = geoms[i];
rayHits.Add(rayHit);
}
}
}
return rayHits.Count > 0;
}
/// <summary>
/// Returns all the geoms intersected by the point which collide with the given collision group
/// </summary>
/// <param name="pt">Pt</param>
/// <param name="hitGeoms">Intersected Geoms</param>
/// <param name="collisionGroup">Collision Group</param>
/// <returns>Returns true if at least 1 geom is intersected by the point</returns>
public bool PointCastAll(Vector2 pt, out List<gxtGeom> hitGeoms, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL)
{
if (collisionGroup == gxtCollisionGroup.NONE)
{
hitGeoms = new List<gxtGeom>();
return false;
}
hitGeoms = broadphaseCollider.PointCastAll(pt);
for (int i = hitGeoms.Count - 1; i >= 0; i--)
{
if (!CanCollide(collisionGroup, hitGeoms[i]))
hitGeoms.RemoveAt(i);
else if (!gxtGJKCollider.Contains(hitGeoms[i].Polygon, pt))
hitGeoms.RemoveAt(i);
}
return hitGeoms.Count != 0;
}
/// <summary>
/// Returns one geom intersected by the pt which will collide with the given collision group
/// In cases where multiple geoms are intersected by the point, the geom is chosen whose centroid
/// is closest to the passed in point
/// </summary>
/// <param name="pt">Pt</param>
/// <param name="hitGeom">Intersected Geom</param>
/// <param name="collisionGroup">Collision Group</param>
/// <returns>Returns true if a geom is intersected by the point</returns>
public bool PointCast(Vector2 pt, out gxtGeom hitGeom, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL)
{
hitGeom = null;
List<gxtGeom> geoms;
if (PointCastAll(pt, out geoms, collisionGroup))
{
float minDist = float.MaxValue;
float tmpDist;
for (int i = 0; i < geoms.Count; i++)
{
// should really be by the world centroid instead
tmpDist = (pt - geoms[i].GetWorldCentroid()).LengthSquared();
if (tmpDist < minDist)
{
hitGeom = geoms[i];
minDist = tmpDist;
}
}
return true;
}
return false;
}
/// <summary>
/// Determines if an object with the given collision group can collide with the geom
/// </summary>
/// <param name="collisionGroup">Collision Group</param>
/// <param name="geom">Geom</param>
/// <returns>If object and geom can collide</returns>
public bool CanCollide(gxtCollisionGroup collisionGroup, gxtGeom geom)
{
if (!geom.CollisionEnabled)
return false;
if ((collisionGroup & geom.CollisionGroups) == gxtCollisionGroup.NONE)
return false;
return true;
}
public void AddCollisionGroupName(string name, gxtCollisionGroup collisionGroup)
{
/*
if (collisionGroupsMap.ContainsValue(collisionGroup))
{
gxtLog.WriteLineV(gxtVerbosityLevel.WARNING, "Collision group exists under another name");
}
*/
collisionGroupsMap.Add(name, collisionGroup);
}
/// <summary>
///
/// </summary>
/// <param name="aabb"></param>
/// <param name="hitGeoms"></param>
/// <param name="collisionGroup"></param>
/// <returns></returns>
public bool AABBCastAll(gxtAABB aabb, out List<gxtGeom> hitGeoms, gxtCollisionGroup collisionGroup = gxtCollisionGroup.ALL)
{
gxtDebug.Assert(aabb.Extents.X >= 0.0f && aabb.Extents.Y >= 0.0f, "An AABB with negative extents will not intersect anything");
if (collisionGroup == gxtCollisionGroup.NONE)
{
hitGeoms = new List<gxtGeom>();
return false;
}
hitGeoms = broadphaseCollider.AABBCastAll(aabb);
if (hitGeoms.Count == 0)
return false;
gxtPolygon boxPolygon = gxtGeometry.ComputePolygonFromAABB(aabb);
gxtPolygon geomPolygon;
for (int i = hitGeoms.Count - 1; i >= 0; i--)
{
if (!CanCollide(collisionGroup, hitGeoms[i]))
hitGeoms.RemoveAt(i);
else
{
geomPolygon = hitGeoms[i].Polygon;
if (!gxtGJKCollider.Intersects(ref boxPolygon, aabb.Position, ref geomPolygon, hitGeoms[i].Position))
hitGeoms.RemoveAt(i);
}
}
return hitGeoms.Count != 0;
}
