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public AddPortalCullingPlanes ( |
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| portal | ||
| return | int | |
public int AddPortalCullingPlanes( Portal 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.Type == PORTAL_TYPE.PORTAL_TYPE_AABB ||
portal.Type == PORTAL_TYPE.PORTAL_TYPE_SPHERE )
{
PCPlane newPlane = GetUnusedCullingPlane();
newPlane.SetFromAxiomPlane( mOriginPlane );
newPlane.Portal = portal;
mActiveCullingPlanes.Add( newPlane );
addedcullingplanes++;
return addedcullingplanes;
}
// 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;
PlaneSide pt0_side, pt1_side;
bool visible;
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;
foreach ( PCPlane plane in mActiveCullingPlanes )
{
pt0_side = plane.GetSide( portal.getDerivedCorner( i ) );
pt1_side = plane.GetSide( portal.getDerivedCorner( j ) );
if ( pt0_side == PlaneSide.Negative &&
pt1_side == PlaneSide.Negative )
{
// the portal edge was actually completely culled by one of culling planes
visible = false;
}
}
if ( visible )
{
// add the plane created from the two portal corner points and the frustum location
// to the culling plane
PCPlane newPlane = GetUnusedCullingPlane();
if ( projType == Projection.Orthographic ) // use camera direction if projection is orthographic.
{
newPlane.Redefine( portal.getDerivedCorner( j ) + mOriginPlane.Normal,
portal.getDerivedCorner( j ), portal.getDerivedCorner( i ) );
}
else
{
newPlane.Redefine( mOrigin, portal.getDerivedCorner( j ), portal.getDerivedCorner( i ) );
}
newPlane.Portal = portal;
mActiveCullingPlanes.Add( 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();
newPlane.Redefine( portal.getDerivedCorner( 2 ), portal.getDerivedCorner( 1 ), portal.getDerivedCorner( 0 ) );
newPlane.Portal = portal;
mActiveCullingPlanes.Add( newPlane );
addedcullingplanes++;
}
return addedcullingplanes;
}
/** (recursive) check the given light against all portals in the zone
* NOTE: This is the default implementation, which doesn't take advantage
* of any zone-specific optimizations for checking portal visibility
*/
public override void CheckLightAgainstPortals( PCZLight light, ulong frameCount, PCZFrustum portalFrustum, Portal ignorePortal )
{
foreach ( Portal p in mPortals )
{
//Portal * p = *it;
if ( p != ignorePortal )
{
// calculate the direction vector from light to portal
Vector3 lightToPortal = p.getDerivedCP() - light.GetDerivedPosition();
if ( portalFrustum.IsObjectVisible( p ) )
{
// portal is facing the light, but some light types need to
// check illumination radius too.
PCZone targetZone = p.getTargetZone();
switch ( light.Type )
{
case LightType.Point:
// point lights - just check if within illumination range
if ( lightToPortal.Length <= light.AttenuationRange )
{
// if portal is quad portal it must be pointing towards the light
if ( ( p.Type == PORTAL_TYPE.PORTAL_TYPE_QUAD && lightToPortal.Dot( p.getDerivedDirection() ) < 0.0 ) ||
( p.Type != PORTAL_TYPE.PORTAL_TYPE_QUAD ) )
{
if ( !light.AffectsZone( targetZone ) )
{
light.AddZoneToAffectedZonesList( targetZone );
if ( targetZone.LastVisibleFrame == frameCount )
{
light.AffectsVisibleZone = true;
}
// set culling frustum from the portal
portalFrustum.AddPortalCullingPlanes( p );
// recurse into the target zone of the portal
p.getTargetZone().CheckLightAgainstPortals( light,
frameCount,
portalFrustum,
p.getTargetPortal() );
// remove the planes added by this portal
portalFrustum.RemovePortalCullingPlanes( p );
}
}
}
break;
case LightType.Directional:
// directionals have infinite range, so just make sure
// the direction is facing the portal
if ( lightToPortal.Dot( light.DerivedDirection ) >= 0.0 )
{
// if portal is quad portal it must be pointing towards the light
if ( ( p.Type == PORTAL_TYPE.PORTAL_TYPE_QUAD && lightToPortal.Dot( p.getDerivedDirection() ) < 0.0 ) ||
( p.Type == PORTAL_TYPE.PORTAL_TYPE_QUAD ) )
{
if ( !light.AffectsZone( targetZone ) )
{
light.AddZoneToAffectedZonesList( targetZone );
if ( targetZone.LastVisibleFrame == frameCount )
{
light.AffectsVisibleZone = true;
}
// set culling frustum from the portal
portalFrustum.AddPortalCullingPlanes( p );
// recurse into the target zone of the portal
p.getTargetZone().CheckLightAgainstPortals( light,
frameCount,
portalFrustum,
p.getTargetPortal() );
// remove the planes added by this portal
portalFrustum.RemovePortalCullingPlanes( p );
}
}
}
break;
case LightType.Spotlight:
// spotlights - just check if within illumination range
// Technically, we should check if the portal is within
// the cone of illumination, but for now, we'll leave that
// as a future optimisation.
if ( lightToPortal.Length <= light.AttenuationRange )
{
// if portal is quad portal it must be pointing towards the light
if ( ( p.Type == PORTAL_TYPE.PORTAL_TYPE_QUAD && lightToPortal.Dot( p.getDerivedDirection() ) < 0.0 ) ||
( p.Type != PORTAL_TYPE.PORTAL_TYPE_QUAD ) )
{
if ( !light.AffectsZone( targetZone ) )
{
light.AddZoneToAffectedZonesList( targetZone );
if ( targetZone.LastVisibleFrame == frameCount )
{
light.AffectsVisibleZone = true;
}
// set culling frustum from the portal
portalFrustum.AddPortalCullingPlanes( p );
// recurse into the target zone of the portal
p.getTargetZone().CheckLightAgainstPortals( light,
frameCount,
portalFrustum,
p.getTargetPortal() );
// remove the planes added by this portal
portalFrustum.RemovePortalCullingPlanes( p );
}
}
}
break;
}
}
}
}
}
