class HorizonCulling in Tinman.Terrain.Meshing

The HorizonCulling class traverses the filtered mesh (see FilterIn), performs a visibility tests for each mesh sector with the horizon outline and culls away all sectors that are below of it (see SectorCull).

sealed class	HorizonCulling	implements	IMeshAction
			IMeshBoundMinRadius
			IMeshBoundMinSize
		extends	MeshTraversal

Remarks

Starting with the mesh sectors nearest to the camera position, a horizon outline is built. All mesh sectors that do not alter the horizon (i.e. those that are occluded by others) will be culled away (see SectorCull).

The following vertex data semantics are used by this class:

• required : Position
• required : Radius
• required : Elevation
• required : ElevationMinMax
• optional : LevelOfDetail

Public / Attributes

CameraInfo

The object that provides the current camera position.

public property	CameraInfo { get set }
type	CameraInfo
value	[not-null]	The camera position provider.
implements	ICameraInfoDependent.CameraInfo

CanPerform

Can the action be performed?

public property	CanPerform { get }
type	bool
value		true if the CLOD mesh action can be performed, false if not (calling Perform will return silently in this case).
implements	IMeshAction.CanPerform

FilterIn

The mesh tree input filter to use for querying sector culling and marks.

public property	FilterIn { get set }
type	MeshTreeFilter
value		The filter or null.
inherited	MeshTraversal.FilterIn

Remarks:

The default value is null (i.e. all mesh sectors are visited).

See also:

MeshTree.GetRoot
MeshTree.GetChild
MeshTree.GetDown

FilterOut

The mesh tree output filter to use for performing sector culling and marking.

public property	FilterOut { get set }
type	MeshTreeFilter
value		The mesh tree filter object.
inherited	MeshTraversal.FilterOut

Remarks:

This MeshTreeFilter is not reset automatically. The application is responsible to call Reset.

The default value is null (i.e. the input filter is used in that case).

See also:

MeshTree.SectorCull
MeshTree.SectorMark
MeshTree.SectorMarkRoots

HasMesh

Has this object been bound to an IMesh object?

public property	HasMesh { get }
type	bool
value		true if this object is currently bound to an IMesh, false if not.
inherited	MeshBoundBase.HasMesh

Mesh

The CLOD mesh this object is currently bound to.

public property	Mesh { get }
type	IMesh
value		The CLOD mesh or null.
inherited	MeshBoundBase.Mesh

MinRadius

The mesh sector quadtree is traversed until the bounding sphere radius of a mesh sector falls below this limit.

public property	MinRadius { get set }
type	float32
value	[>=0]	The minimum bounding sphere radius, in terrain-space.
implements	IMeshBoundMinRadius.MinRadius

Remarks:

The default value is 0 (i.e. the entire mesh is traversed).

MinSize

The mesh sector quadtree is traversed until the projected screen-size of a mesh sector falls below this limit.

public property	MinSize { get set }
type	float32
value	[>=0]	Minimum sector size, in screen-space.
implements	IMeshBoundMinSize.MinSize

Remarks:

This value is the square root of the approximated pixel area of the mesh sector on the screen.

The default value is 256.0f pixels.

Tree

The filtered MeshTree of this mesh traversal object.

public property	Tree { get }
type	MeshTree
value	[not-null]	The filtered MeshTree object or null if this object is not bound.
inherited	MeshTraversal.Tree

Viewport

The current viewport object.

public property	Viewport { get set }
type	Viewport
value	[not-null]	The viewport object.
implements	IViewportDependent.Viewport

Public / Constructors

HorizonCulling

Creates a new instance of HorizonCulling.

public constructor

HorizonCulling ()

Public / Methods

MeshBind

Binds this object to the given IMesh.

public override method	MeshBind (IMesh mesh)
params	mesh		The mesh object.
overrides	MeshTraversal.MeshBind

MeshUnbind

Unbinds this object from its current IMesh.

public override method	MeshUnbind ()
overrides	MeshBoundBase.MeshUnbind

Perform

Performs the action on the currently bound CLOD mesh.

public method	Perform ()
implements	IMeshAction.Perform

See also:

IMeshAction.CanPerform

VisitFaces

Visits the given mesh root sectors.

public method	VisitFaces (CubemapFace meshFace = CubemapFace.All)
params	meshFace		The mesh face to traverse. Defaults to All.
inherited	MeshTraversal.VisitFaces

VisitQuadrant

Visits a quadrant of the given mesh sector on the current face, assuming that the corresponding child mesh sector does not exist.

public override method	VisitQuadrant (int32 sector, int32 childIdx)
params	sector		Index of center vertex of sector to visit.
	childIdx		Index of non-existing child sector in sector.
implements	MeshTraversal.VisitQuadrant

Remarks:

The quadtree data structure for visiting the given sector can be obtained by getting the Tree property of the current mesh (see MeshBind.

VisitSector

Visits the given mesh sector on the current face.

public override method	VisitSector (int32 sector)
params	sector		Index of center vertex of sector to visit.
implements	MeshTraversal.VisitSector

Remarks:

The quadtree data structure for visiting the given sector can be obtained by getting the Tree property of the current mesh (see MeshBind.