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vtkTextRenderer Class Referenceabstract

Interface for generating images and path data from string data, using multiple backends. More...

#include <vtkTextRenderer.h>

Inheritance diagram for vtkTextRenderer:
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Collaboration diagram for vtkTextRenderer:
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Classes

struct  Metrics
 

Public Types

enum  Backend {
  Default = -1 , Detect = 0 , FreeType , MathText ,
  UserBackend = 16
}
 Available backends. More...
 
typedef vtkObject Superclass
 

Public Member Functions

virtual vtkTypeBool IsA (const char *type)
 Return 1 if this class is the same type of (or a subclass of) the named class. More...
 
vtkTextRendererNewInstance () const
 
void PrintSelf (ostream &os, vtkIndent indent) override
 Methods invoked by print to print information about the object including superclasses. More...
 
virtual bool FreeTypeIsSupported ()
 Test for availability of various backends. More...
 
virtual bool MathTextIsSupported ()
 
void SetScaleToPowerOfTwo (bool scale)
 Set to true if the graphics implementation requires texture image dimensions to be a power of two. More...
 
virtual void SetDefaultBackend (int)
 The backend to use when none is specified. More...
 
virtual int GetDefaultBackend ()
 The backend to use when none is specified. More...
 
virtual int DetectBackend (const vtkStdString &str)
 Determine the appropriate back end needed to render the given string. More...
 
bool GetBoundingBox (vtkTextProperty *tprop, const vtkStdString &str, int bbox[4], int dpi, int backend=Default)
 Given a text property and a string, get the bounding box {xmin, xmax, ymin, ymax} of the rendered string in pixels. More...
 
bool GetMetrics (vtkTextProperty *tprop, const vtkStdString &str, Metrics &metrics, int dpi, int backend=Default)
 Given a text property and a string, get some metrics for the rendered string. More...
 
bool RenderString (vtkTextProperty *tprop, const vtkStdString &str, vtkImageData *data, int textDims[2], int dpi, int backend=Default)
 Given a text property and a string, this function initializes the vtkImageData *data and renders it in a vtkImageData. More...
 
int GetConstrainedFontSize (const vtkStdString &str, vtkTextProperty *tprop, int targetWidth, int targetHeight, int dpi, int backend=Default)
 This function returns the font size (in points) and sets the size in tprop that is required to fit the string in the target rectangle. More...
 
bool StringToPath (vtkTextProperty *tprop, const vtkStdString &str, vtkPath *path, int dpi, int backend=Default)
 Given a text property and a string, this function populates the vtkPath path with the outline of the rendered string. More...
 
- Public Member Functions inherited from vtkObject
 vtkBaseTypeMacro (vtkObject, vtkObjectBase)
 
virtual void DebugOn ()
 Turn debugging output on. More...
 
virtual void DebugOff ()
 Turn debugging output off. More...
 
bool GetDebug ()
 Get the value of the debug flag. More...
 
void SetDebug (bool debugFlag)
 Set the value of the debug flag. More...
 
virtual void Modified ()
 Update the modification time for this object. More...
 
virtual vtkMTimeType GetMTime ()
 Return this object's modified time. More...
 
void RemoveObserver (unsigned long tag)
 
void RemoveObservers (unsigned long event)
 
void RemoveObservers (const char *event)
 
void RemoveAllObservers ()
 
vtkTypeBool HasObserver (unsigned long event)
 
vtkTypeBool HasObserver (const char *event)
 
vtkTypeBool InvokeEvent (unsigned long event)
 
vtkTypeBool InvokeEvent (const char *event)
 
std::string GetObjectDescription () const override
 The object description printed in messages and PrintSelf output. More...
 
unsigned long AddObserver (unsigned long event, vtkCommand *, float priority=0.0f)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
unsigned long AddObserver (const char *event, vtkCommand *, float priority=0.0f)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkCommandGetCommand (unsigned long tag)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObserver (vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObservers (unsigned long event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
void RemoveObservers (const char *event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkTypeBool HasObserver (unsigned long event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
vtkTypeBool HasObserver (const char *event, vtkCommand *)
 Allow people to add/remove/invoke observers (callbacks) to any VTK object. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(), float priority=0.0f)
 Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, void(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
 Overloads to AddObserver that allow developers to add class member functions as callbacks for events. More...
 
template<class U , class T >
unsigned long AddObserver (unsigned long event, U observer, bool(T::*callback)(vtkObject *, unsigned long, void *), float priority=0.0f)
 Allow user to set the AbortFlagOn() with the return value of the callback method. More...
 
vtkTypeBool InvokeEvent (unsigned long event, void *callData)
 This method invokes an event and return whether the event was aborted or not. More...
 
vtkTypeBool InvokeEvent (const char *event, void *callData)
 This method invokes an event and return whether the event was aborted or not. More...
 
virtual void SetObjectName (const std::string &objectName)
 Set/get the name of this object for reporting purposes. More...
 
virtual std::string GetObjectName () const
 Set/get the name of this object for reporting purposes. More...
 
- Public Member Functions inherited from vtkObjectBase
const char * GetClassName () const
 Return the class name as a string. More...
 
virtual vtkIdType GetNumberOfGenerationsFromBase (const char *name)
 Given the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). More...
 
virtual void Delete ()
 Delete a VTK object. More...
 
virtual void FastDelete ()
 Delete a reference to this object. More...
 
void InitializeObjectBase ()
 
void Print (ostream &os)
 Print an object to an ostream. More...
 
void Register (vtkObjectBase *o)
 Increase the reference count (mark as used by another object). More...
 
virtual void UnRegister (vtkObjectBase *o)
 Decrease the reference count (release by another object). More...
 
int GetReferenceCount ()
 Return the current reference count of this object. More...
 
void SetReferenceCount (int)
 Sets the reference count. More...
 
bool GetIsInMemkind () const
 A local state flag that remembers whether this object lives in the normal or extended memory space. More...
 
virtual void PrintHeader (ostream &os, vtkIndent indent)
 Methods invoked by print to print information about the object including superclasses. More...
 
virtual void PrintTrailer (ostream &os, vtkIndent indent)
 Methods invoked by print to print information about the object including superclasses. More...
 
virtual bool UsesGarbageCollector () const
 Indicate whether the class uses vtkGarbageCollector or not. More...
 

Static Public Member Functions

static vtkTypeBool IsTypeOf (const char *type)
 
static vtkTextRendererSafeDownCast (vtkObjectBase *o)
 
static vtkTextRendererNew ()
 This is a singleton pattern New. More...
 
static vtkTextRendererGetInstance ()
 Return the singleton instance with no reference counting. More...
 
- Static Public Member Functions inherited from vtkObject
static vtkObjectNew ()
 Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...
 
static void BreakOnError ()
 This method is called when vtkErrorMacro executes. More...
 
static void SetGlobalWarningDisplay (vtkTypeBool val)
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static void GlobalWarningDisplayOn ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static void GlobalWarningDisplayOff ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
static vtkTypeBool GetGlobalWarningDisplay ()
 This is a global flag that controls whether any debug, warning or error messages are displayed. More...
 
- Static Public Member Functions inherited from vtkObjectBase
static vtkTypeBool IsTypeOf (const char *name)
 Return 1 if this class type is the same type of (or a subclass of) the named class. More...
 
static vtkIdType GetNumberOfGenerationsFromBaseType (const char *name)
 Given a the name of a base class of this class type, return the distance of inheritance between this class type and the named class (how many generations of inheritance are there between this class and the named class). More...
 
static vtkObjectBaseNew ()
 Create an object with Debug turned off, modified time initialized to zero, and reference counting on. More...
 
static void SetMemkindDirectory (const char *directoryname)
 The name of a directory, ideally mounted -o dax, to memory map an extended memory space within. More...
 
static bool GetUsingMemkind ()
 A global state flag that controls whether vtkObjects are constructed in the usual way (the default) or within the extended memory space. More...
 

Protected Member Functions

virtual vtkObjectBaseNewInstanceInternal () const
 
 vtkTextRenderer ()
 
 ~vtkTextRenderer () override
 
virtual bool GetBoundingBoxInternal (vtkTextProperty *tprop, const vtkStdString &str, int bbox[4], int dpi, int backend)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual bool GetMetricsInternal (vtkTextProperty *tprop, const vtkStdString &str, Metrics &metrics, int dpi, int backend)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual bool RenderStringInternal (vtkTextProperty *tprop, const vtkStdString &str, vtkImageData *data, int textDims[2], int dpi, int backend)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual int GetConstrainedFontSizeInternal (const vtkStdString &str, vtkTextProperty *tprop, int targetWidth, int targetHeight, int dpi, int backend)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual bool StringToPathInternal (vtkTextProperty *tprop, const vtkStdString &str, vtkPath *path, int dpi, int backend)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual void SetScaleToPowerOfTwoInternal (bool scale)=0
 Virtual methods for concrete implementations of the public methods. More...
 
virtual void CleanUpFreeTypeEscapes (vtkStdString &str)
 Replace all instances of "\$" with "$". More...
 
- Protected Member Functions inherited from vtkObject
 vtkObject ()
 
 ~vtkObject () override
 
void RegisterInternal (vtkObjectBase *, vtkTypeBool check) override
 
void UnRegisterInternal (vtkObjectBase *, vtkTypeBool check) override
 
void InternalGrabFocus (vtkCommand *mouseEvents, vtkCommand *keypressEvents=nullptr)
 These methods allow a command to exclusively grab all events. More...
 
void InternalReleaseFocus ()
 These methods allow a command to exclusively grab all events. More...
 
- Protected Member Functions inherited from vtkObjectBase
 vtkObjectBase ()
 
virtual ~vtkObjectBase ()
 
virtual void ReportReferences (vtkGarbageCollector *)
 
 vtkObjectBase (const vtkObjectBase &)
 
void operator= (const vtkObjectBase &)
 

Static Protected Member Functions

static void SetInstance (vtkTextRenderer *instance)
 Set the singleton instance. More...
 
- Static Protected Member Functions inherited from vtkObjectBase
static vtkMallocingFunction GetCurrentMallocFunction ()
 
static vtkReallocingFunction GetCurrentReallocFunction ()
 
static vtkFreeingFunction GetCurrentFreeFunction ()
 
static vtkFreeingFunction GetAlternateFreeFunction ()
 

Protected Attributes

vtksys::RegularExpression * MathTextRegExp
 
vtksys::RegularExpression * MathTextRegExp2
 
vtksys::RegularExpression * MathTextRegExpColumn
 
int DefaultBackend
 The backend to use when none is specified. More...
 
- Protected Attributes inherited from vtkObject
bool Debug
 
vtkTimeStamp MTime
 
vtkSubjectHelper * SubjectHelper
 
std::string ObjectName
 
- Protected Attributes inherited from vtkObjectBase
std::atomic< int32_t > ReferenceCount
 
vtkWeakPointerBase ** WeakPointers
 

Static Protected Attributes

static vtkTextRendererInstance
 The singleton instance and the singleton cleanup instance. More...
 
static vtkTextRendererCleanup Cleanup
 The singleton instance and the singleton cleanup instance. More...
 

Friends

class vtkTextRendererCleanup
 

Detailed Description

Interface for generating images and path data from string data, using multiple backends.

vtkTextRenderer produces images, bounding boxes, and vtkPath objects that represent text. The advantage of using this class is to easily integrate mathematical expressions into renderings by automatically switching between FreeType and MathText backends. If the input string contains at least two "$" symbols separated by text, the MathText backend will be used. Alternatively, the presence of unescaped "|" symbols defines multicolumn lines, which are processed with the MathText backend.

If the string does not meet these criteria, or if no MathText implementation is available, the faster FreeType rendering facilities are used. Literal $ symbols can be used by escaping them with backslashes, "\$" (or "\\$" if the string is set programmatically).

For example, "Acceleration ($\\frac{m}{s^2}$)" will use MathText, but "\\$500, \\$100" will use FreeType.

By default, the backend is set to Detect, which determines the backend based on the contents of the string. This can be changed by setting the DefaultBackend ivar.

Note that this class is abstract – link to the vtkRenderingFreetype module to get the default implementation.

Tests:
vtkTextRenderer (Tests)

Definition at line 70 of file vtkTextRenderer.h.

Member Typedef Documentation

◆ Superclass

Definition at line 118 of file vtkTextRenderer.h.

Member Enumeration Documentation

◆ Backend

Available backends.

FreeType and MathText are provided in the default implementation of this interface. Enum values less than 16 are reserved. Custom overrides should define other backends starting at 16.

Enumerator
Default 
Detect 
FreeType 
MathText 
UserBackend 

Definition at line 143 of file vtkTextRenderer.h.

Constructor & Destructor Documentation

◆ vtkTextRenderer()

vtkTextRenderer::vtkTextRenderer ( )
protected

◆ ~vtkTextRenderer()

vtkTextRenderer::~vtkTextRenderer ( )
overrideprotected

Member Function Documentation

◆ IsTypeOf()

static vtkTypeBool vtkTextRenderer::IsTypeOf ( const char *  type)
static

◆ IsA()

virtual vtkTypeBool vtkTextRenderer::IsA ( const char *  name)
virtual

Return 1 if this class is the same type of (or a subclass of) the named class.

Returns 0 otherwise. This method works in combination with vtkTypeMacro found in vtkSetGet.h.

Reimplemented from vtkObjectBase.

Reimplemented in vtkMathTextFreeTypeTextRenderer.

◆ SafeDownCast()

static vtkTextRenderer* vtkTextRenderer::SafeDownCast ( vtkObjectBase o)
static

◆ NewInstanceInternal()

virtual vtkObjectBase* vtkTextRenderer::NewInstanceInternal ( ) const
protectedvirtual

◆ NewInstance()

vtkTextRenderer* vtkTextRenderer::NewInstance ( ) const

◆ PrintSelf()

void vtkTextRenderer::PrintSelf ( ostream &  os,
vtkIndent  indent 
)
overridevirtual

Methods invoked by print to print information about the object including superclasses.

Typically not called by the user (use Print() instead) but used in the hierarchical print process to combine the output of several classes.

Reimplemented from vtkObject.

Reimplemented in vtkMathTextFreeTypeTextRenderer.

◆ New()

static vtkTextRenderer* vtkTextRenderer::New ( )
static

This is a singleton pattern New.

There will be only ONE reference to a vtkTextRenderer subclass object per process. Clients that call this method must use Delete() on the object so that reference counting will work. The single instance will be unreferenced when the program exits. You should just use the static GetInstance() method anyway to get the singleton. This method may return NULL if the object factory cannot find an override.

◆ GetInstance()

static vtkTextRenderer* vtkTextRenderer::GetInstance ( )
static

Return the singleton instance with no reference counting.

May return NULL if the object factory cannot find an override.

◆ SetDefaultBackend()

virtual void vtkTextRenderer::SetDefaultBackend ( int  )
virtual

The backend to use when none is specified.

Default: Detect

◆ GetDefaultBackend()

virtual int vtkTextRenderer::GetDefaultBackend ( )
virtual

The backend to use when none is specified.

Default: Detect

◆ DetectBackend()

virtual int vtkTextRenderer::DetectBackend ( const vtkStdString str)
virtual

Determine the appropriate back end needed to render the given string.

◆ FreeTypeIsSupported()

virtual bool vtkTextRenderer::FreeTypeIsSupported ( )
inlinevirtual

Test for availability of various backends.

Reimplemented in vtkMathTextFreeTypeTextRenderer.

Definition at line 171 of file vtkTextRenderer.h.

◆ MathTextIsSupported()

virtual bool vtkTextRenderer::MathTextIsSupported ( )
inlinevirtual

Reimplemented in vtkMathTextFreeTypeTextRenderer.

Definition at line 172 of file vtkTextRenderer.h.

◆ GetBoundingBox()

bool vtkTextRenderer::GetBoundingBox ( vtkTextProperty tprop,
const vtkStdString str,
int  bbox[4],
int  dpi,
int  backend = Default 
)
inline

Given a text property and a string, get the bounding box {xmin, xmax, ymin, ymax} of the rendered string in pixels.

The origin of the bounding box is the anchor point described by the horizontal and vertical justification text property variables. Return true on success, false otherwise.

Definition at line 182 of file vtkTextRenderer.h.

◆ GetMetrics()

bool vtkTextRenderer::GetMetrics ( vtkTextProperty tprop,
const vtkStdString str,
Metrics metrics,
int  dpi,
int  backend = Default 
)
inline

Given a text property and a string, get some metrics for the rendered string.

Return true on success, false otherwise.

Definition at line 195 of file vtkTextRenderer.h.

◆ RenderString()

bool vtkTextRenderer::RenderString ( vtkTextProperty tprop,
const vtkStdString str,
vtkImageData data,
int  textDims[2],
int  dpi,
int  backend = Default 
)
inline

Given a text property and a string, this function initializes the vtkImageData *data and renders it in a vtkImageData.

Return true on success, false otherwise. If using the overload that specifies "textDims", the array will be overwritten with the pixel width and height defining a tight bounding box around the text in the image, starting from the upper-right corner. This is used when rendering for a texture on graphics hardware that requires texture image dimensions to be a power of two; textDims can be used to determine the texture coordinates needed to cleanly fit the text on the target. The origin of the image's extents is aligned with the anchor point described by the text property's vertical and horizontal justification options.

Definition at line 217 of file vtkTextRenderer.h.

◆ GetConstrainedFontSize()

int vtkTextRenderer::GetConstrainedFontSize ( const vtkStdString str,
vtkTextProperty tprop,
int  targetWidth,
int  targetHeight,
int  dpi,
int  backend = Default 
)
inline

This function returns the font size (in points) and sets the size in tprop that is required to fit the string in the target rectangle.

The computed font size will be set in tprop as well. If an error occurs, this function will return -1.

Definition at line 231 of file vtkTextRenderer.h.

◆ StringToPath()

bool vtkTextRenderer::StringToPath ( vtkTextProperty tprop,
const vtkStdString str,
vtkPath path,
int  dpi,
int  backend = Default 
)
inline

Given a text property and a string, this function populates the vtkPath path with the outline of the rendered string.

The origin of the path coordinates is aligned with the anchor point described by the text property's horizontal and vertical justification options. Return true on success, false otherwise.

Definition at line 247 of file vtkTextRenderer.h.

◆ SetScaleToPowerOfTwo()

void vtkTextRenderer::SetScaleToPowerOfTwo ( bool  scale)
inline

Set to true if the graphics implementation requires texture image dimensions to be a power of two.

Default is true, but this member will be set appropriately by vtkOpenGLRenderWindow::OpenGLInitContext when GL is inited.

Definition at line 260 of file vtkTextRenderer.h.

◆ GetBoundingBoxInternal()

virtual bool vtkTextRenderer::GetBoundingBoxInternal ( vtkTextProperty tprop,
const vtkStdString str,
int  bbox[4],
int  dpi,
int  backend 
)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ GetMetricsInternal()

virtual bool vtkTextRenderer::GetMetricsInternal ( vtkTextProperty tprop,
const vtkStdString str,
Metrics metrics,
int  dpi,
int  backend 
)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ RenderStringInternal()

virtual bool vtkTextRenderer::RenderStringInternal ( vtkTextProperty tprop,
const vtkStdString str,
vtkImageData data,
int  textDims[2],
int  dpi,
int  backend 
)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ GetConstrainedFontSizeInternal()

virtual int vtkTextRenderer::GetConstrainedFontSizeInternal ( const vtkStdString str,
vtkTextProperty tprop,
int  targetWidth,
int  targetHeight,
int  dpi,
int  backend 
)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ StringToPathInternal()

virtual bool vtkTextRenderer::StringToPathInternal ( vtkTextProperty tprop,
const vtkStdString str,
vtkPath path,
int  dpi,
int  backend 
)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ SetScaleToPowerOfTwoInternal()

virtual void vtkTextRenderer::SetScaleToPowerOfTwoInternal ( bool  scale)
protectedpure virtual

Virtual methods for concrete implementations of the public methods.

Implemented in vtkMathTextFreeTypeTextRenderer.

◆ SetInstance()

static void vtkTextRenderer::SetInstance ( vtkTextRenderer instance)
staticprotected

Set the singleton instance.

Call Delete() on the supplied instance after setting it to fix the reference count.

◆ CleanUpFreeTypeEscapes()

virtual void vtkTextRenderer::CleanUpFreeTypeEscapes ( vtkStdString str)
protectedvirtual

Replace all instances of "\$" with "$".

Friends And Related Function Documentation

◆ vtkTextRendererCleanup

friend class vtkTextRendererCleanup
friend

Definition at line 262 of file vtkTextRenderer.h.

Member Data Documentation

◆ Instance

vtkTextRenderer* vtkTextRenderer::Instance
staticprotected

The singleton instance and the singleton cleanup instance.

Definition at line 295 of file vtkTextRenderer.h.

◆ Cleanup

vtkTextRendererCleanup vtkTextRenderer::Cleanup
staticprotected

The singleton instance and the singleton cleanup instance.

Definition at line 296 of file vtkTextRenderer.h.

◆ MathTextRegExp

vtksys::RegularExpression* vtkTextRenderer::MathTextRegExp
protected

Definition at line 299 of file vtkTextRenderer.h.

◆ MathTextRegExp2

vtksys::RegularExpression* vtkTextRenderer::MathTextRegExp2
protected

Definition at line 300 of file vtkTextRenderer.h.

◆ MathTextRegExpColumn

vtksys::RegularExpression* vtkTextRenderer::MathTextRegExpColumn
protected

Definition at line 301 of file vtkTextRenderer.h.

◆ DefaultBackend

int vtkTextRenderer::DefaultBackend
protected

The backend to use when none is specified.

Default: Detect

Definition at line 313 of file vtkTextRenderer.h.


The documentation for this class was generated from the following file: