/* special function that returns true only when sphere fully fits inside the frustum. */
bool PCZFrustum::isFullyVisible(const Sphere& bound) const
{
// Check originplane if told to
if (mUseOriginPlane)
{
if (mOriginPlane.getDistance(bound.getCenter()) <= bound.getRadius() ||
mOriginPlane.getSide(bound.getCenter()) != Plane::POSITIVE_SIDE)
{
return false;
}
}
// For each extra active culling plane,
// see if the sphere is not on the positive side
// If so, object is not fully visible
PCPlaneList::const_iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane* plane = *pit;
if (plane->getDistance(bound.getCenter()) <= bound.getRadius() ||
plane->getSide(bound.getCenter()) != Plane::POSITIVE_SIDE)
{
return false;
}
pit++;
}
return true;
}
bool PCZFrustum::isVisible( const Sphere & bound) const
{
// Check originplane if told to
if (mUseOriginPlane)
{
Plane::Side side = mOriginPlane.getSide(bound.getCenter());
if (side == Plane::NEGATIVE_SIDE)
{
Real dist = mOriginPlane.getDistance(bound.getCenter());
if (dist > bound.getRadius())
{
return false;
}
}
}
// For each extra active culling plane, see if the entire sphere is on the negative side
// If so, object is not visible
PCPlaneList::const_iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
Plane::Side xside = plane->getSide(bound.getCenter());
if (xside == Plane::NEGATIVE_SIDE)
{
Real dist = plane->getDistance(bound.getCenter());
if (dist > bound.getRadius())
{
return false;
}
}
pit++;
}
return true;
}
/* A 'more detailed' check for visibility of an AAB. This function returns
none, partial, or full for visibility of the box. This is useful for
stuff like Octree leaf culling */
PCZFrustum::Visibility PCZFrustum::getVisibility( const AxisAlignedBox &bound )
{
// Null boxes always invisible
if ( bound.isNull() )
return NONE;
// Get centre of the box
Vector3 centre = bound.getCenter();
// Get the half-size of the box
Vector3 halfSize = bound.getHalfSize();
bool all_inside = true;
// Check originplane if told to
if (mUseOriginPlane)
{
Plane::Side side = mOriginPlane.getSide(centre, halfSize);
if (side == Plane::NEGATIVE_SIDE)
{
return NONE;
}
// We can't return now as the box could be later on the negative side of another plane.
if(side == Plane::BOTH_SIDE)
{
all_inside = false;
}
}
// For each active culling plane, see if the entire aabb is on the negative side
// If so, object is not visible
PCPlaneList::iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
Plane::Side xside = plane->getSide(centre, halfSize);
if(xside == Plane::NEGATIVE_SIDE)
{
return NONE;
}
// We can't return now as the box could be later on the negative side of a plane.
if(xside == Plane::BOTH_SIDE)
{
all_inside = false;
break;
}
pit++;
}
if ( all_inside )
return FULL;
else
return PARTIAL;
}
bool PCZFrustum::isVisible( const AxisAlignedBox & bound) const
{
// Null boxes are always invisible
if (bound.isNull()) return false;
// Infinite boxes are always visible
if (bound.isInfinite()) return true;
// Get centre of the box
Vector3 centre = bound.getCenter();
// Get the half-size of the box
Vector3 halfSize = bound.getHalfSize();
// Check originplane if told to
if (mUseOriginPlane)
{
Plane::Side side = mOriginPlane.getSide(centre, halfSize);
if (side == Plane::NEGATIVE_SIDE)
{
return false;
}
}
// For each extra active culling plane, see if the entire aabb is on the negative side
// If so, object is not visible
PCPlaneList::const_iterator pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
Plane::Side xside = plane->getSide(centre, halfSize);
if (xside == Plane::NEGATIVE_SIDE)
{
return false;
}
pit++;
}
return true;
}
// calculate culling planes from portal and frustum
// origin and add to list of culling planes
// NOTE: returns 0 if portal was completely culled by existing planes
// returns > 0 if culling planes are added (# is planes added)
int PCZFrustum::addPortalCullingPlanes(PortalBase* portal)
{
int addedcullingplanes = 0;
// If portal is of type aabb or sphere, add a plane which is same as frustum
// origin plane (ie. redundant). We do this because we need the plane as a flag
// to prevent infinite recursion
if (portal->getType() == PortalBase::PORTAL_TYPE_AABB ||
portal->getType() == PortalBase::PORTAL_TYPE_SPHERE)
{
PCPlane * newPlane = getUnusedCullingPlane();
newPlane->setFromOgrePlane(mOriginPlane);
newPlane->setPortal(portal);
mActiveCullingPlanes.push_front(newPlane);
addedcullingplanes++;
return addedcullingplanes;
}
// only do this check if it's an anti portal since it's double facing.
bool flipPlane = false;
if (portal->getTypeFlags() == AntiPortalFactory::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);
// it's facing away from the frustum. Flip the planes.
if (dotProduct > 0) flipPlane = true;
}
// For portal Quads: Up to 4 planes can be added by the sides of a portal quad.
// Each plane is created from 2 corners (world space) of the portal and the
// frustum origin (world space).
int i,j;
Plane::Side pt0_side, pt1_side;
bool visible;
PCPlaneList::iterator pit;
for (i=0;i<4;i++)
{
// first check if both corners are outside of one of the existing planes
j = i+1;
if (j > 3)
{
j = 0;
}
visible = true;
pit = mActiveCullingPlanes.begin();
while ( pit != mActiveCullingPlanes.end() )
{
PCPlane * plane = *pit;
pt0_side = plane->getSide(portal->getDerivedCorner(i));
pt1_side = plane->getSide(portal->getDerivedCorner(j));
if (pt0_side == Plane::NEGATIVE_SIDE &&
pt1_side == Plane::NEGATIVE_SIDE)
{
// the portal edge was actually completely culled by one of culling planes
visible = false;
break;
}
pit++;
}
if (visible)
{
// add the plane created from the two portal corner points and the frustum location
// to the culling plane
PCPlane * newPlane = getUnusedCullingPlane();
if (mProjType == PT_ORTHOGRAPHIC) // use camera direction if projection is orthographic.
{
if (flipPlane)
{
newPlane->redefine(portal->getDerivedCorner(j) + mOriginPlane.normal,
portal->getDerivedCorner(i), portal->getDerivedCorner(j));
}
else
{
newPlane->redefine(portal->getDerivedCorner(j) + mOriginPlane.normal,
portal->getDerivedCorner(j), portal->getDerivedCorner(i));
}
}
else
{
if (flipPlane)
{
newPlane->redefine(mOrigin,
portal->getDerivedCorner(i),
portal->getDerivedCorner(j));
}
else
{
newPlane->redefine(mOrigin,
portal->getDerivedCorner(j),
portal->getDerivedCorner(i));
}
}
newPlane->setPortal(portal);
mActiveCullingPlanes.push_front(newPlane);
addedcullingplanes++;
}
}
// if we added ANY planes from the quad portal, we should add the plane of the
// portal itself as an additional culling plane.
if (addedcullingplanes > 0)
{
PCPlane * newPlane = getUnusedCullingPlane();
if (flipPlane)
{
newPlane->redefine(
portal->getDerivedCorner(2),
portal->getDerivedCorner(0),
portal->getDerivedCorner(1));
}
else
{
newPlane->redefine(
portal->getDerivedCorner(2),
portal->getDerivedCorner(1),
portal->getDerivedCorner(0));
}
newPlane->setPortal(portal);
mActiveCullingPlanes.push_back(newPlane);
addedcullingplanes++;
}
return addedcullingplanes;
}
/* 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;
}