TerraCrater Class Reference

Craters. More...

#include <archestree.h>

Inheritance diagram for TerraCrater:

Public Member Functions
	TerraCrater (const Vector2 &, const double &, const double &, const double &, const double &)
	Create a crater.
	~TerraCrater ()
	Empty.
virtual ScalarAlpha	ElevationAlpha (const Vector2 &) const
	Compute the elevation and weight.
virtual int	Memory () const
	Compute the size of a node.
Public Member Functions inherited from TerraPrimitive
	TerraPrimitive (const double &=1.0, const double &=1.0)
	Create a primitive.
	~TerraPrimitive ()
	Recusively destroy the sub-trees.
int	Traversal (const Vector2 &) const
	Compute the number of nodes that are traversed when evaluating the tree.
double	Alpha (const double &) const
	Compute the falloff function.
Public Member Functions inherited from TerraNode
	TerraNode (const Box2 &=Box2::Infinity)
	Create a node.
virtual Box2	GetBox () const
	Returns the bouding box of a node.
virtual double	Elevation (const Vector2 &) const
	Compute the elevation at a given position.
virtual double	Alpha (const Vector2 &) const
	Compute the alpha mask at a given position.
virtual Vector2	Gradient (const Vector2 &) const
	Compute the gradient at a given position.
virtual Vector	Normal (const Vector2 &) const
	Compute the normal at a given position.
virtual void	writeJson (QJsonObject &)
	Compute the Json Document of the subtree.
ScalarField2	Sample (const Array2 &) const
	Create a discrete scalar field by sampling the elevation over a given domain.
ScalarField2	Alpha (const Array2 &) const
	Create a discrete scalar field by sampling the elevation over a given domain.
void	Blend (HeightField &) const
	Blend a given node with an existing terrain over an input heightfield.
void	Add (HeightField &) const
	Add a given node with an existing heightfield.
virtual void	Draw (QGraphicsScene &) const
	Renders the node into a QGraphicsScene.

Protected Member Functions
double	CrestAlpha (const double &) const
	Compute the noise dampening as a function of the distance to the center.

Protected Attributes
Vector2	center
	Center.
double	rc
	Crest radius.
double	depth
	Hole depth.
double	uz
	Ridge elevation.
Cubic	outside
	Profile curves of the crater.
SimplexTurbulence2	elevation
	Warping and elevation noises.
Protected Attributes inherited from TerraPrimitive
double	alpha = 1.0
	Weight.
Protected Attributes inherited from TerraNode
Box2	box = Box2::Infinity
	Bounding box.

Additional Inherited Members
Static Protected Attributes inherited from TerraNode
static const double	epsilon = 1e-2
	Epsilon value for gradient computations.

Detailed Description

Craters.

Constructor & Destructor Documentation

TerraCrater()

TerraCrater::TerraCrater ( const Vector2 & c, const double & cr, const double & e, const double & depth, const double & uplift )

explicit

Create a crater.

Parameters

c	Center.
r	Crest radius.
e	External radius.
depth	Depth of the crater.
uplift	Crest height.

References TerraNode::box, center, depth, elevation, Cubic::Hermite(), outside, rc, TerraPrimitive::TerraPrimitive(), and uz.

Referenced by Memory().

Member Function Documentation

CrestAlpha()

double TerraCrater::CrestAlpha ( const double & d ) const

protected

Compute the noise dampening as a function of the distance to the center.

Parameters

d

Distance

References Linear::Affine(), and rc.

Referenced by ElevationAlpha().

ElevationAlpha()

ScalarAlpha TerraCrater::ElevationAlpha ( const Vector2 & p ) const

virtual

Compute the elevation and weight.

Parameters

p

Point.

Reimplemented from TerraNode.

References TerraNode::box, center, CrestAlpha(), elevation, ScalarAlpha::Empty, rc, Cubic::SmoothCompact(), and Math::Sqr().

Memory()

int TerraCrater::Memory ( ) const

virtual

Compute the size of a node.

Reimplemented from TerraNode.

References TerraCrater().