public void SplitPrepare(Portal p)
{
Vertices = p.Vertices;
Normal = p.Normal;
Normal.MirrorNormal();
Parent = null;
}
public static Frustum PortalFrustumIntersect(Portal portal, Frustum emitter, Render render)
{
if (portal.DestRoom == null)
return null;
if (portal.Normal.Distance(render.Camera.Position) < SPLIT_EPSILON)
// non face or degenerate to the line portal
return null;
if (portal.DestRoom.Frustum.Count > 0 && emitter.HasParent(portal.DestRoom.Frustum[0]))
return null; // Abort infinite loop!
var inDist = false;
var inFace = false;
foreach (var v in portal.Vertices)
{
if (!inDist && render.Camera.Frustum.Normal.Distance(v) < render.Camera.DistFar)
inDist = true;
if (!inFace && emitter.Normal.Distance(v) > 0.0)
inFace = true;
if (inDist && inFace)
break;
}
if (!inDist || !inDist)
return null;
// Search for the first free room's frustum
portal.DestRoom.Frustum.Add(new Frustum());
var currentGen = portal.DestRoom.Frustum.Last();
currentGen.SplitPrepare(portal); // prepare for clipping
if (currentGen.SplitByPlane(emitter.Normal)) // splitting by main frustum clip plane
{
for (var i = 0; i < emitter.Vertices.Count; i++)
{
if(!currentGen.SplitByPlane(emitter.Planes[i]))
{
portal.DestRoom.Frustum.RemoveAt(portal.DestRoom.Frustum.Count - 1);
return null;
}
}
currentGen.GenClipPlanes(render.Camera); // all is OK, let's generate clip planes
currentGen.Parent = emitter; // add parent pointer
currentGen.ParentsCount = emitter.ParentsCount + 1;
portal.DestRoom.MaxPath = Math.Max(portal.DestRoom.MaxPath, currentGen.ParentsCount); // maximum path to the room
return currentGen;
}
portal.DestRoom.Frustum.RemoveAt(portal.DestRoom.Frustum.Count - 1);
return null;
}