CS::Math::Noise::Module::Terrace Class Reference
[Modifier Modules]
Noise module that maps the output value from a source module onto a terraceforming curve. More...
#include <cstool/noise/module/terrace.h>
Public Member Functions  
void  AddControlPoint (double value) 
Adds a control point to the terraceforming curve.  
void  ClearAllControlPoints () 
Deletes all the control points on the terraceforming curve.  
const double *  GetControlPointArray () const 
Returns a pointer to the array of control points on the terraceforming curve.  
int  GetControlPointCount () const 
Returns the number of control points on the terraceforming curve.  
virtual int  GetSourceModuleCount () const 
Returns the number of source modules required by this noise module.  
virtual double  GetValue (double x, double y, double z) const 
Generates an output value given the coordinates of the specified input value.  
void  InvertTerraces (bool invert=true) 
Enables or disables the inversion of the terraceforming curve between the control points.  
bool  IsTerracesInverted () const 
Determines if the terraceforming curve between the control.  
void  MakeControlPoints (int controlPointCount) 
Creates a number of equallyspaced control points that range from.  
Terrace ()  
Constructor.  
~Terrace ()  
Destructor.  
Protected Member Functions  
int  FindInsertionPos (double value) 
Determines the array index in which to insert the control point into the internal control point array.  
void  InsertAtPos (int insertionPos, double value) 
Inserts the control point at the specified position in the internal control point array.  
Protected Attributes  
int  m_controlPointCount 
Number of control points stored in this noise module.  
bool  m_invertTerraces 
Determines if the terraceforming curve between all control points is inverted.  
double *  m_pControlPoints 
Array that stores the control points. 
Detailed Description
Noise module that maps the output value from a source module onto a terraceforming curve.
This noise module maps the output value from the source module onto a terraceforming curve. The start of this curve has a slope of zero; its slope then smoothly increases. This curve also contains control points which resets the slope to zero at that point, producing a "terracing" effect. Refer to the following illustration:
To add a control point to this noise module, call the AddControlPoint() method.
An application must add a minimum of two control points to the curve. If this is not done, the GetValue() method fails. The control points can have any value, although no two control points can have the same value. There is no limit to the number of control points that can be added to the curve.
This noise module clamps the output value from the source module if that value is less than the value of the lowest control point or greater than the value of the highest control point.
This noise module is often used to generate terrain features such as your stereotypical desert canyon.
This noise module requires one source module.
Definition at line 72 of file terrace.h.
Constructor & Destructor Documentation
CS::Math::Noise::Module::Terrace::Terrace  (  ) 
Constructor.
CS::Math::Noise::Module::Terrace::~Terrace  (  ) 
Destructor.
Member Function Documentation
void CS::Math::Noise::Module::Terrace::AddControlPoint  (  double  value  ) 
Adds a control point to the terraceforming curve.
 Parameters:

value The value of the control point to add.
 Precondition:
 No two control points have the same value.
 Exceptions:

CS::Math::Noise::ExceptionInvalidParam An invalid parameter was specified; see the preconditions for more information. Two or more control points define the terraceforming curve. The start of this curve has a slope of zero; its slope then smoothly increases. At the control points, its slope resets to zero. It does not matter which order these points are added.
void CS::Math::Noise::Module::Terrace::ClearAllControlPoints  (  ) 
Deletes all the control points on the terraceforming curve.
 Postcondition:
 All control points on the terraceforming curve are deleted.
int CS::Math::Noise::Module::Terrace::FindInsertionPos  (  double  value  )  [protected] 
Determines the array index in which to insert the control point into the internal control point array.
 Parameters:

value The value of the control point.
 Returns:
 The array index in which to insert the control point.
 Precondition:
 No two control points have the same value.
 Exceptions:

CS::Math::Noise::ExceptionInvalidParam An invalid parameter was specified; see the preconditions for more information. By inserting the control point at the returned array index, this class ensures that the control point array is sorted by value. The code that maps a value onto the curve requires a sorted control point array.
const double* CS::Math::Noise::Module::Terrace::GetControlPointArray  (  )  const [inline] 
Returns a pointer to the array of control points on the terraceforming curve.
 Returns:
 A pointer to the array of control points in this noise module.
Two or more control points define the terraceforming curve. The start of this curve has a slope of zero; its slope then smoothly increases. At the control points, its slope resets to zero. Before calling this method, call GetControlPointCount() to determine the number of control points in this array. It is recommended that an application does not store this pointer for later use since the pointer to the array may change if the application calls another method of this object.
int CS::Math::Noise::Module::Terrace::GetControlPointCount  (  )  const [inline] 
virtual int CS::Math::Noise::Module::Terrace::GetSourceModuleCount  (  )  const [inline, virtual] 
Returns the number of source modules required by this noise module.
 Returns:
 The number of source modules required by this noise module.
Implements CS::Math::Noise::Module::Module.
virtual double CS::Math::Noise::Module::Terrace::GetValue  (  double  x,  
double  y,  
double  z  
)  const [virtual] 
Generates an output value given the coordinates of the specified input value.
 Parameters:

x The x coordinate of the input value. y The y coordinate of the input value. z The z coordinate of the input value.
 Returns:
 The output value.
 Precondition:
 All source modules required by this noise module have been passed to the SetSourceModule() method.
Before an application can call this method, it must first connect all required source modules via the SetSourceModule() method. If these source modules are not connected to this noise module, this method raises a debug assertion.
To determine the number of source modules required by this noise module, call the GetSourceModuleCount() method.
Implements CS::Math::Noise::Module::Module.
void CS::Math::Noise::Module::Terrace::InsertAtPos  (  int  insertionPos,  
double  value  
)  [protected] 
Inserts the control point at the specified position in the internal control point array.
 Parameters:

insertionPos The zerobased array position in which to insert the control point. value The value of the control point.
To make room for this new control point, this method reallocates the control point array and shifts all control points occurring after the insertion position up by one. Because the curve mapping algorithm in this noise module requires that all control points in the array be sorted by value, the new control point should be inserted at the position in which the order is still preserved.
void CS::Math::Noise::Module::Terrace::InvertTerraces  (  bool  invert = true 
)  [inline] 
bool CS::Math::Noise::Module::Terrace::IsTerracesInverted  (  )  const [inline] 
void CS::Math::Noise::Module::Terrace::MakeControlPoints  (  int  controlPointCount  ) 
Creates a number of equallyspaced control points that range from.
1 to +1.
 Parameters:

controlPointCount The number of control points to generate.
 Precondition:
 The number of control points must be greater than or equal to 2.
 Postcondition:
 The previous control points on the terraceforming curve are deleted.
 Exceptions:

CS::Math::Noise::ExceptionInvalidParam An invalid parameter was specified; see the preconditions for more information. Two or more control points define the terraceforming curve. The start of this curve has a slope of zero; its slope then smoothly increases. At the control points, its slope resets to zero.
Member Data Documentation
int CS::Math::Noise::Module::Terrace::m_controlPointCount [protected] 
bool CS::Math::Noise::Module::Terrace::m_invertTerraces [protected] 
double* CS::Math::Noise::Module::Terrace::m_pControlPoints [protected] 
The documentation for this class was generated from the following file:
 cstool/noise/module/terrace.h
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