ddgTBinTree Class Reference

List of all members.

Public Members
		ddgTBinTree (ddgTreeIndex i, int dr = 0, int dc = 0, bool mirror = false)
		Construct a Bintree mesh.
		~ddgTBinTree (void)
		Destroy the Bintree mesh.
	void	freeChain (void)
		Free all the cached nodes in this bintree.
	ddgCacheIndex	chain (void)
		Free all the cached nodes in this bintree.
	unsigned int	visTriangle (void)
		Return the number of visible triangles which this bin tree is managing.
	void	visTriangle (unsigned int v)
		Set the number of visible triangles which this bin tree is managing.
	ddgTBinTree*	pNeighbourDiag (void)
		Return the neighbouring bin tree.
	ddgTBinTree*	pNeighbourTop (void)
		Return the neighbouring bin tree.
	ddgTBinTree*	pNeighbourLeft (void)
		Return the neighbouring bin tree.
	void	pNeighbourDiag (ddgTBinTree* t)
		Set the neighbouring bin tree.
	void	pNeighbourTop (ddgTBinTree* t)
		Set the neighbouring bin tree.
	void	pNeighbourLeft (ddgTBinTree* t)
		Set the neighbouring bin tree.
	int	dc (void)
		Returns the column offset in the height map.
	int	dr (void)
		Returns the row offset in the height map.
	bool	mirror (void)
		Returns true if this is a mirrored mesh.
	bool	init (void)
		Initialize the bin tree.
	void	tcacheId ( ddgTriIndex tindex, ddgCacheIndex ci )
		Set the cache index for a triangle.
	ddgCacheIndex	tcacheId ( ddgTriIndex tindex )
		Get the cache index for a triangle.
	short	rawHeight ( ddgTriIndex tindex )
		Get the raw height for a triangle.
	short	rawMinVal ( ddgTriIndex tindex )
		Get the min height for a triangle block.
	short	rawMaxVal ( ddgTriIndex tindex )
		Get the max height for a triangle block.
	ddgVisState	vis (void)
		Return toplevel visibility state.
	ddgVisState	vis (ddgTriIndex tindex)
		Return the objects visibility state.
	void	vis (ddgTriIndex tindex, ddgVisState v)
		Set the objects visibility state.
	int	priority (ddgTriIndex tindex)
		Return the priority of this triangle.
	void	priority (ddgTriIndex tindex, int p)
		Set the priority of this triangle.
	float	priorityFactor (ddgTriIndex tindex)
		Return the priority of this triangle.
	void	priorityFactor (ddgTriIndex tindex, float pf)
		Set the priority of this triangle.
	ddgCacheIndex	qscacheIndex (ddgTriIndex tindex)
		Return split cache index if any.
	void	qscacheIndex (ddgTriIndex tindex, ddgCacheIndex i)
		Set split cache index if any.
	ddgCacheIndex	qmcacheIndex (ddgTriIndex tindex)
		Return split cache index if any.
	void	qmcacheIndex (ddgTriIndex tindex, ddgCacheIndex i)
		Set split cache index if any.
	float	heightByPos (unsigned int r, unsigned int c)
		Return the height of a location on the bintree mesh.
	float	treeHeight (unsigned int r, unsigned int c, float dx, float dz)
		Get height of mesh at a real location. More...
	void	vertex (ddgTriIndex tindex, ddgVector3 *vout)
		Get vertex location in world space from the cache, return the cache index if we have it.
	void	textureC (unsigned int tindex, ddgVector2 *vout)
		Get texture coord data, as a value from 0 to 1 on the bintree.
	ddgVisState	visibilityTriangle (ddgTriIndex tvc)
		Calculate visibility of a triangle.
	bool	visible (ddgTriIndex i)
		Is triangle visible (even partially)?
	bool	fullyvisible (ddgTriIndex i)
		Is triangle fully visible?
	void	initTriangle ( unsigned int level, ddgTriIndex va, ddgTriIndex v1, ddgTriIndex v0, ddgTriIndex vc)
		Initialize precomputed parameters. More...
	void	insertSQ (ddgTriIndex tindex, ddgPriority p, ddgCacheIndex ci, ddgVisState parentVis )
		Split queue operations.
	ddgCacheIndex	removeSQ (ddgTriIndex tindex)
		Remove triangle tindex.
	void	insertMQ (ddgTriIndex tindex, ddgPriority p)
		Split queue operations.
	void	removeMQ (ddgTriIndex tindex)
	void	forceSplit ( ddgTriIndex tindex)
		Split a triangle into 2.
	void	forceMerge ( ddgTriIndex tindex)
		Merge 4 triangles into 2.
	void	updateSplit (ddgTriIndex tindex, ddgVisState newVis )
		Recursively update the split info for a triangle which is in the mesh.
	void	updateMerge (ddgTriIndex tindex, ddgPriority pr)
		Update the merge info for a triangle which is in the mesh.
	ddgPriority	priorityCalc (ddgTriIndex tindex, float priorityFactor)
		Calculate priority of triangle tindex We assume that we only get called.
	unsigned int	index (void)
		Return the index in the mesh.
	bool	rayTest ( ddgVector3 p1, ddgVector3 p2, ddgTriIndex tindex, int depth = -1 )
		Ray test a line segment to see if it collides with the terrain. More...
Static Public Members
	unsigned int	level (ddgTriIndex i)
		Return the level of this triangle based on its index.
	bool	isRight (ddgTriIndex i)
		If this is odd (right) or even(left) child in the tree.
	bool	isLeft (ddgTriIndex i)
		If this is odd (right) or even(left) child in the tree.
	ddgTriIndex	parent (ddgTriIndex i)
		Return the parent of this element.
	ddgTriIndex	right (ddgTriIndex i)
		Return the index of the left child.
	ddgTriIndex	left (ddgTriIndex i)
		Return the index of the left child.
	void	initContext ( ddgContext context, ddgTBinMesh mesh )
		Initialize view context called once during initialization.
	void	updateContext ( ddgContext context, ddgTBinMesh mesh )
		Update view context called each frame.

Detailed Description

The mesh is a hierarchical binary tree of triangles. The structure of this mesh can be precomputed and stored as a large look-up-table. Triangles are organized in the array so they can easily find their parent or children as well as all the triangles of their own generation. This can all be done with index arithmetic (ie. no need for pointers).

Member Function Documentation

Get height of mesh at a real location.

Coords should be unscaled in x,z direction.

Initialize precomputed parameters.

Recusively calculate a convex hull for a triangle. Splitting occurs along this points parent's Passed in are the triangles which carry the points that describe the current triangle. va is immediate parent. v1 and v0 are the sub triangles of va.

Ray test a line segment to see if it collides with the terrain.

A depth of 0 implies testing to the leaf nodes. Returns true and the index of the triangle if a hit occured. Returns false otherwise.

ddgTBinTree Class Reference

Public Members

Static Public Members

Detailed Description

Member Function Documentation