AtlasOldActivationHeightfield Class Reference [Old Atlas Editor Code]

#include <atlasOldGenerator.h>

Inheritance diagram for AtlasOldActivationHeightfield:

Detailed Description

Adds activation level tracking functionality for AtlasOldHeightfield.

Activation levels are part of our BTT-based mesh decimation system. So if we end up using a different/better mesh decimation algorithm, we can simply go back to using AHFs.

Public Member Functions

AtlasOldActivationHeightfield (const U32 sizeLog2, const F32 sampleSpacing, const F32 heightScale)

virtual ~AtlasOldActivationHeightfield ()

S8 getLevel (Point2I pos)

void setLevel (Point2I pos, S8 level)

void activate (Point2I pos, S8 level)

HeightType getHeightAtLOD (Point2I pos, S8 level)

Returns the height of the mesh as simplified to the specified level of detail.

void generateChunkFile (Stream *s, S8 treeDepth, F32 baseMaxError)

Generate LOD chunks from the heightfield.

bool dumpHeightAtLOD (S8 level, const char *filename)

bool dumpActivationLevels (const char *filename)

Static Public Attributes

static bool smDoChecks

If set, do a variety of checks during generation to ensure we have valid activation levels and so forth.

static bool smGenerateDebugData

If set, set a debug flag in the file header and insert sentinel values in the datastream to ensure we've made valid data.

Protected Member Functions

HeightType heightQuery (S8 level, Point2I pos, Point2I a, Point2I r, Point2I l)

Returns the height of the query point (x,z) within the triangle (a, r, l), as tesselated to the specified LOD.

void generateEmptyTOC (Stream *s, S32 treeDepth)

Append an empty table-of-contents for a fully-populated quadtree, and rewind the stream to the start of the contents.

void generateNodeData (Stream *s, Point2I pos, S32 log_size, S32 level, HeightType min=0, HeightType max=0)

Given a square of data, with northwest corner at pos and comprising ((1<<logSize)+1) verts along each axis, this function generates the mesh using verts which are active at the given level.

void generateSkirt (AtlasOldMesher *cm, const Point2I a, const Point2I b, const S8 level)

void generateBlock (AtlasOldMesher *cm, const S8 activationLevel, S32 logSize, Point2I c)

void generateQuadrant (AtlasOldMesher *cm, AtlasOldGenState &s, Point2I l, Point2I t, Point2I r, S32 recursionLevel)

void propagateActivationLevel (Point2I c, S8 level, S8 targetLevel)

Does a quadtree descent through the heightfield, in the square with center at (cx, cz) and size of (2 ^ (level + 1) + 1).

S8 checkPropagation (Point2I c, S8 level)

Debugging function -- verifies that activation level dependencies are correct throughout the tree.

void update (F32 baseMaxError, Point2I a, Point2I r, Point2I l)

Given the triangle, computes an error value and activation level for its base vertex, and recurses to child triangles.

Protected Attributes

S8 * mActivationLevels

Constructor & Destructor Documentation

AtlasOldActivationHeightfield::AtlasOldActivationHeightfield	(	const U32	sizeLog2,
		const F32	sampleSpacing,
		const F32	heightScale
	)

virtual AtlasOldActivationHeightfield::~AtlasOldActivationHeightfield ( ) [virtual]

Member Function Documentation

HeightType AtlasOldActivationHeightfield::heightQuery	(	S8	level,
		Point2I	pos,
		Point2I	a,
		Point2I	r,
		Point2I	l
	)			`[protected]`

Returns the height of the query point (x,z) within the triangle (a, r, l), as tesselated to the specified LOD.

Return value is in heightfield discrete coords. To get meters, multiply by the heightfield's vertical scale.

void AtlasOldActivationHeightfield::generateEmptyTOC	(	Stream *	s,
		S32	treeDepth
	)			`[protected]`

Append an empty table-of-contents for a fully-populated quadtree, and rewind the stream to the start of the contents.

Use this to make room for TOC at the beginning of the file, while bulk vert/index data gets appended after the TOC. (Helper function, the data is later filled in by the data generation process.)

void AtlasOldActivationHeightfield::generateNodeData	(	Stream *	s,
		Point2I	pos,
		S32	log_size,
		S32	level,
		HeightType	min = `0`,
		HeightType	max = `0`
	)			`[protected]`

Given a square of data, with northwest corner at pos and comprising ((1<<logSize)+1) verts along each axis, this function generates the mesh using verts which are active at the given level.

If we're not at the base level (level > 0), then also recurses to quadtree child nodes and generates their data.

void AtlasOldActivationHeightfield::generateSkirt	(	AtlasOldMesher *	cm,
		const Point2I	a,
		const Point2I	b,
		const S8	level
	)			`[protected]`

void AtlasOldActivationHeightfield::generateBlock	(	AtlasOldMesher *	cm,
		const S8	activationLevel,
		S32	logSize,
		Point2I	c
	)			`[protected]`

void AtlasOldActivationHeightfield::generateQuadrant	(	AtlasOldMesher *	cm,
		AtlasOldGenState &	s,
		Point2I	l,
		Point2I	t,
		Point2I	r,
		S32	recursionLevel
	)			`[protected]`

void AtlasOldActivationHeightfield::propagateActivationLevel	(	Point2I	c,
		S8	level,
		S8	targetLevel
	)			`[protected]`

Does a quadtree descent through the heightfield, in the square with center at (cx, cz) and size of (2 ^ (level + 1) + 1).

Descends until level == target_level, and then propagates this square's child center verts to the corresponding edge vert, and the edge verts to the center. Essentially the quadtree meshing update dependency graph per Thatcher Ulrich's Gamasutra article. Must call this with successively increasing target_level to get correct propagation.

S8 AtlasOldActivationHeightfield::checkPropagation	(	Point2I	c,
		S8	level
	)			`[protected]`

Debugging function -- verifies that activation level dependencies are correct throughout the tree.

void AtlasOldActivationHeightfield::update	(	F32	baseMaxError,
		Point2I	a,
		Point2I	r,
		Point2I	l
	)			`[protected]`

Given the triangle, computes an error value and activation level for its base vertex, and recurses to child triangles.

S8 AtlasOldActivationHeightfield::getLevel ( Point2I pos )

void AtlasOldActivationHeightfield::setLevel	(	Point2I	pos,
		S8	level
	)

void AtlasOldActivationHeightfield::activate	(	Point2I	pos,
		S8	level
	)

HeightType AtlasOldActivationHeightfield::getHeightAtLOD	(	Point2I	pos,
		S8	level
	)

Returns the height of the mesh as simplified to the specified level of detail.

Returns:: value is in heightfield discrete coords. To get meters, multiply by the heightfield's vertical scale.

void AtlasOldActivationHeightfield::generateChunkFile	(	Stream *	s,
		S8	treeDepth,
		F32	baseMaxError
	)

Generate LOD chunks from the heightfield.

Parameters:

	tree_depth	Determines the depth of the chunk quadtree.
	base_max_error	Specifies the maximum allowed geometric vertex error, at the finest level of detail.

bool AtlasOldActivationHeightfield::dumpHeightAtLOD	(	S8	level,
		const char *	filename
	)

bool AtlasOldActivationHeightfield::dumpActivationLevels ( const char * filename )

Member Data Documentation

S8* AtlasOldActivationHeightfield::mActivationLevels [protected]

bool AtlasOldActivationHeightfield::smDoChecks [static]

If set, do a variety of checks during generation to ensure we have valid activation levels and so forth.

Also tells NVTriStrip to validate what we push through it.

bool AtlasOldActivationHeightfield::smGenerateDebugData [static]

If set, set a debug flag in the file header and insert sentinel values in the datastream to ensure we've made valid data.