/// <summary>
/// This may be entered multiple times with different planes if more than
/// one portal sees into the area.
/// </summary>
/// <param name="areaNumber"></param>
/// <param name="portalStack"></param>
private void AddAreaReferences(int areaNumber, PortalStack portalStack)
{
// mark the viewCount, so r_showPortals can display the
// considered portals
_portalAreas[areaNumber].ViewCount = idE.RenderSystem.ViewCount;
// add the models and lights, using more precise culling to the planes
AddAreaEntityReferences(areaNumber, portalStack);
// TODO: AddAreaLightRefs( areaNum, ps );
}
/// <summary>
/// Any models that are visible through the current portalStack will have their scissor.
/// </summary>
/// <param name="areaNumber"></param>
/// <param name="portalStack"></param>
private void AddAreaEntityReferences(int areaNumber, PortalStack portalStack)
{
PortalArea area = _portalAreas[areaNumber];
for(AreaReference areaRef = area.EntityReference.NextArea; areaRef != area.EntityReference; areaRef = areaRef.NextArea)
{
idRenderEntity entity = areaRef.Entity;
// debug tool to allow viewing of only one entity at a time
if((idE.CvarSystem.GetInteger("r_singleEntity") > 0) && (idE.CvarSystem.GetInteger("r_singleEntity") != entity.EntityIndex))
{
continue;
}
// remove decals that are completely faded away
// TODO: R_FreeEntityDefFadedDecals( entity, tr.viewDef->renderView.time );
// check for completely suppressing the model
if(idE.CvarSystem.GetBool("r_skipSuppress") == false)
{
if(entity.Parameters.SuppressSurfaceInViewID == idE.RenderSystem.ViewDefinition.RenderView.ViewID)
{
continue;
}
else if(entity.Parameters.AllowSurfaceInViewID != idE.RenderSystem.ViewDefinition.RenderView.ViewID)
{
continue;
}
}
// cull reference bounds
if(CullEntityByPortals(entity, portalStack) == true)
{
// we are culled out through this portal chain, but it might
// still be visible through others
continue;
}
ViewEntity viewEntity = SetEntityDefViewEntity(entity);
// possibly expand the scissor rect
viewEntity.ScissorRectangle.Union(portalStack.Rectangle);
}
}
private void FloodViewThroughArea(Vector3 origin, int areaNumber, PortalStack portalStack)
{
int i, j;
idWinding winding; // we won't overflow because MAX_PORTAL_PLANES = 20
PortalStack check;
PortalStack newStack;
PortalArea area = _portalAreas[areaNumber];
// cull models and lights to the current collection of planes
AddAreaReferences(areaNumber, portalStack);
if(_areaScreenRect[areaNumber].IsEmpty == true)
{
_areaScreenRect[areaNumber] = portalStack.Rectangle;
}
else
{
_areaScreenRect[areaNumber].Union(portalStack.Rectangle);
}
// go through all the portals
Portal portal;
for(portal = area.Portals; portal != null; portal = portal.Next)
{
// an enclosing door may have sealed the portal off
if((portal.DoublePortal.BlockingBits & PortalConnection.BlockView) == PortalConnection.BlockView)
{
continue;
}
// make sure this portal is facing away from the view
float d = portal.Plane.Distance(origin);
if(d < -0.1f)
{
continue;
}
// make sure the portal isn't in our stack trace,
// which would cause an infinite loop
for(check = portalStack; check != null; check = check.Next)
{
if(check.Portal == portal)
{
break; // don't recursively enter a stack
}
}
if(check != null)
{
continue; // already in stack
}
// if we are very close to the portal surface, don't bother clipping
// it, which tends to give epsilon problems that make the area vanish
if(d < 1.0f)
{
// go through this portal
newStack = portalStack;
newStack.Portal = portal;
newStack.Next = portalStack;
FloodViewThroughArea(origin, portal.IntoArea, newStack);
continue;
}
// clip the portal winding to all of the planes
winding = portal.Winding;
for(j = 0; j < portalStack.PortalPlaneCount; j++)
{
Plane neg = new Plane(-portalStack.PortalPlanes[j].Normal, -portalStack.PortalPlanes[j].D);
if(winding.ClipInPlace(neg, 0) == false)
{
break;
}
}
if(winding.PointCount == 0)
{
continue; // portal not visible
}
// see if it is fogged out
if(PortalIsFoggedOut(portal) == true)
{
continue;
}
// go through this portal
newStack = new PortalStack();
newStack.Portal = portal;
newStack.Next = portalStack;
// find the screen pixel bounding box of the remaining portal
// so we can scissor things outside it
newStack.Rectangle = ScreenRectangleFromWinding(winding, idE.RenderSystem.IdentitySpace);
// slop might have spread it a pixel outside, so trim it back
newStack.Rectangle.Intersect(portalStack.Rectangle);
// generate a set of clipping planes that will further restrict
// the visible view beyond just the scissor rect
int addPlanes = winding.PointCount;
if(addPlanes > idE.MaxPortalPlanes)
{
addPlanes = idE.MaxPortalPlanes;
}
newStack.PortalPlaneCount = 0;
for(i = 0; i < addPlanes; i++)
{
j = i + 1;
if(j == winding.PointCount)
{
j = 0;
}
Vector3 v1 = origin - winding[i];
Vector3 v2 = origin - winding[j];
newStack.PortalPlanes[newStack.PortalPlaneCount].Normal = Vector3.Cross( v2, v1 );
// if it is degenerate, skip the plane
newStack.PortalPlanes[newStack.PortalPlaneCount].Normalize();
if(newStack.PortalPlanes[newStack.PortalPlaneCount].Normal.Length() < 0.01f)
{
continue;
}
newStack.PortalPlanes[newStack.PortalPlaneCount].FitThroughPoint(origin);
newStack.PortalPlaneCount++;
}
// the last stack plane is the portal plane
newStack.PortalPlanes[newStack.PortalPlaneCount] = portal.Plane;
newStack.PortalPlaneCount++;
FloodViewThroughArea(origin, portal.IntoArea, newStack);
}
}
/// <summary>
/// Finds viewLights and viewEntities by flowing from an origin through the visible portals.
/// origin point can see into. The planes array defines a volume (positive
/// sides facing in) that should contain the origin, such as a view frustum or a point light box.
/// Zero planes assumes an unbounded volume.
/// </summary>
/// <param name="origin"></param>
/// <param name="planes"></param>
private void FlowViewThroughPortals(Vector3 origin, int planeCount, Plane[] planes)
{
View viewDef = idE.RenderSystem.ViewDefinition;
PortalStack portalStack = new PortalStack();
portalStack.Rectangle = viewDef.Scissor;
portalStack.PortalPlaneCount = planeCount;
for(int i = 0; i < planeCount; i++)
{
portalStack.PortalPlanes[i] = planes[i];
}
if(viewDef.AreaNumber < 0)
{
for(int i = 0; i < _portalAreaCount; i++)
{
_areaScreenRect[i] = viewDef.Scissor;
}
// if outside the world, mark everything
for(int i = 0; i < _portalAreaCount; i++)
{
AddAreaReferences(i, portalStack);
}
}
else
{
for(int i = 0; i < _portalAreaCount; i++)
{
_areaScreenRect[i] = new idScreenRect();
}
// flood out through portals, setting area viewCount
FloodViewThroughArea(origin, viewDef.AreaNumber, portalStack);
}
}
/// <summary>
/// Return true if the entity reference bounds do not intersect the current portal chain.
/// </summary>
/// <param name="entity"></param>
/// <param name="portalStack"></param>
/// <returns></returns>
private bool CullEntityByPortals(idRenderEntity entity, PortalStack portalStack)
{
if(idE.CvarSystem.GetBool("r_useEntityCulling") == false)
{
return false;
}
// try to cull the entire thing using the reference bounds.
// we do not yet do callbacks or dynamic model creation,
// because we want to do all touching of the model after
// we have determined all the lights that may effect it,
// which optimizes cache usage
return idHelper.CullLocalBox(entity.ReferenceBounds, entity.ModelMatrix, portalStack.PortalPlaneCount, portalStack.PortalPlanes);
}