// remove culling planes created from the given portal
void PCZFrustum::removePortalCullingPlanes(PortalBase* portal)
{
PCPlaneList::iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
if (plane->getPortal() == portal)
{
// put the plane back in the reservoir
mCullingPlaneReservoir.push_front(plane);
// erase the entry from the active culling plane list
pit = mActiveCullingPlanes.erase(pit);
}
else
{
pit++;
}
}
}
/* special function that returns true only when portal fully fits inside the frustum. */
bool PCZFrustum::isFullyVisible(const PortalBase* portal) const
{
// if portal isn't enabled, it's not visible
if (!portal->getEnabled()) return false;
// if the frustum has no planes, just return true
if (mActiveCullingPlanes.empty())
{
return true;
}
// check if this portal is already in the list of active culling planes (avoid
// infinite recursion case)
PCPlaneList::const_iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
if (plane->getPortal() == portal)
{
return false;
}
pit++;
}
// if portal is of type AABB or Sphere, then use simple bound check against planes
if (portal->getType() == PortalBase::PORTAL_TYPE_AABB)
{
AxisAlignedBox aabb;
aabb.setExtents(portal->getDerivedCorner(0), portal->getDerivedCorner(1));
return isFullyVisible(aabb);
}
else if (portal->getType() == PortalBase::PORTAL_TYPE_SPHERE)
{
return isFullyVisible(portal->getDerivedSphere());
}
// only do this check if it's a portal. (anti portal doesn't care about facing)
if (portal->getTypeFlags() == PortalFactory::FACTORY_TYPE_FLAG)
{
// check if the portal norm is facing the frustum
Vector3 frustumToPortal = portal->getDerivedCP() - mOrigin;
Vector3 portalDirection = portal->getDerivedDirection();
Real dotProduct = frustumToPortal.dotProduct(portalDirection);
if ( dotProduct > 0 )
{
// portal is faced away from Frustum
return false;
}
}
// Check originPlane if told to
if (mUseOriginPlane)
{
// we have to check each corner of the portal
for (int corner = 0; corner < 4; corner++)
{
Plane::Side side = mOriginPlane.getSide(portal->getDerivedCorner(corner));
if (side == Plane::NEGATIVE_SIDE) return false;
}
}
// For each active culling plane, see if any portal points are on the negative
// side. If so, the portal is not fully visible
pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
// we have to check each corner of the portal
for (int corner = 0; corner < 4; corner++)
{
Plane::Side side =plane->getSide(portal->getDerivedCorner(corner));
if (side == Plane::NEGATIVE_SIDE) return false;
}
pit++;
}
// no plane culled all the portal points and the norm
// was facing the frustum, so this portal is fully visible
return true;
}
// NOTE: Everything needs to be updated spatially before this function is
// called including portal corners, frustum planes, etc.
bool PCZFrustum::isVisible(Portal * portal)
{
// if portal isn't open, it's not visible
if (!portal->isOpen())
{
return false;
}
// if the frustum has no planes, just return true
if (mActiveCullingPlanes.size() == 0)
{
return true;
}
// check if this portal is already in the list of active culling planes (avoid
// infinite recursion case)
PCPlaneList::const_iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
if (plane->getPortal() == portal)
{
return false;
}
pit++;
}
// if portal is of type AABB or Sphere, then use simple bound check against planes
if (portal->getType() == Portal::PORTAL_TYPE_AABB)
{
AxisAlignedBox aabb;
aabb.setExtents(portal->getDerivedCorner(0), portal->getDerivedCorner(1));
return isVisible(aabb);
}
else if (portal->getType() == Portal::PORTAL_TYPE_SPHERE)
{
return isVisible(portal->getDerivedSphere());
}
// check if the portal norm is facing the frustum
Vector3 frustumToPortal = portal->getDerivedCP() - mOrigin;
Vector3 portalDirection = portal->getDerivedDirection();
Real dotProduct = frustumToPortal.dotProduct(portalDirection);
if ( dotProduct > 0 )
{
// portal is faced away from Frustum
return false;
}
// check against frustum culling planes
bool visible_flag;
// Check originPlane if told to
if (mUseOriginPlane)
{
// set the visible flag to false
visible_flag = false;
// we have to check each corner of the portal
for (int corner = 0; corner < 4; corner++)
{
Plane::Side side = mOriginPlane.getSide(portal->getDerivedCorner(corner));
if (side != Plane::NEGATIVE_SIDE)
{
visible_flag = true;
}
}
// if the visible_flag is still false, then the origin plane
// culled all the portal points
if (visible_flag == false)
{
// ALL corners on negative side therefore out of view
return false;
}
}
// For each active culling plane, see if all portal points are on the negative
// side. If so, the portal is not visible
pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
// set the visible flag to false
visible_flag = false;
// we have to check each corner of the portal
for (int corner = 0; corner < 4; corner++)
{
Plane::Side side =plane->getSide(portal->getDerivedCorner(corner));
if (side != Plane::NEGATIVE_SIDE)
{
visible_flag = true;
}
}
// if the visible_flag is still false, then this plane
// culled all the portal points
if (visible_flag == false)
{
// ALL corners on negative side therefore out of view
return false;
}
pit++;
}
// no plane culled all the portal points and the norm
// was facing the frustum, so this portal is visible
return true;
}
