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1// @(#)root/gui:$Id$
2// Author: Fons Rademakers 20/5/2003
5 * Copyright (C) 1995-2021, Rene Brun and Fons Rademakers. *
6 * All rights reserved. *
7 * *
8 * For the licensing terms see $ROOTSYS/LICENSE. *
9 * For the list of contributors see $ROOTSYS/README/CREDITS. *
10 *************************************************************************/
12#ifndef ROOT_TGFont
13#define ROOT_TGFont
17// //
18// TGFont and TGFontPool //
19// //
20// Encapsulate fonts used in the GUI system. //
21// TGFontPool provides a pool of fonts. //
22// //
25#include "TNamed.h"
26#include "TGObject.h"
27#include "TRefCnt.h"
29class THashTable;
30class TObjString;
31class TGFont;
33// Flags passed to TGFont::MeasureChars and TGFont::ComputeTextLayout
62 Int_t fAscent; // from baseline to top of font
63 Int_t fDescent; // from baseline to bottom of font
64 Int_t fLinespace; // the sum of the ascent and descent
65 Int_t fMaxWidth; // width of widest character in font
66 Bool_t fFixed; // true if monospace, false otherwise
72 const char *fFamily; // Font family. The most important field.
73 Int_t fPointsize; // Pointsize of font, 0 for default size, or negative number meaning pixel size.
74 Int_t fWeight; // Weight flag; see below for def'n.
75 Int_t fSlant; // Slant flag; see below for def'n.
76 Int_t fUnderline; // Non-zero for underline font.
77 Int_t fOverstrike; // Non-zero for overstrike font.
79 FontAttributes_t(): // default constructor
80 fFamily (0),
81 fPointsize (0),
84 fUnderline (0),
85 fOverstrike(0) { }
87 FontAttributes_t(const FontAttributes_t& f): // copy constructor
91 fSlant (f.fSlant),
95 FontAttributes_t& operator=(const FontAttributes_t& f) // assignment operator
96 {
97 if (this != &f) {
99 fPointsize = f.fPointsize;
100 fWeight = f.fWeight;
101 fSlant = f.fSlant;
102 fUnderline = f.fUnderline;
103 fOverstrike = f.fOverstrike;
104 }
105 return *this;
106 }
112struct LayoutChunk_t;
115class TGTextLayout : public TObject {
117friend class TGFont;
120 const TGFont *fFont; // The font used when laying out the text.
121 const char *fString; // The string that was layed out.
122 Int_t fWidth; // The maximum width of all lines in the text layout.
123 Int_t fNumChunks; // Number of chunks actually used in following array.
124 LayoutChunk_t *fChunks; // Array of chunks. The actual size will be maxChunks.
126 TGTextLayout(const TGTextLayout &tlayout) = delete;
127 void operator=(const TGTextLayout &tlayout) = delete;
130 TGTextLayout(): fFont(nullptr), fString(""), fWidth(0), fNumChunks(0), fChunks(NULL) {}
131 virtual ~TGTextLayout();
133 void DrawText(Drawable_t dst, GContext_t gc, Int_t x, Int_t y,
134 Int_t firstChar, Int_t lastChar) const;
136 Int_t x, Int_t y, Int_t underline) const;
137 Int_t PointToChar(Int_t x, Int_t y) const;
138 Int_t CharBbox(Int_t index, Int_t *x, Int_t *y, Int_t *w, Int_t *h) const;
141 void ToPostscript(TString *dst) const;
143 ClassDef(TGTextLayout,0) // Keep track of string measurement information.
147// The following class is used to keep track of the generic information about a font.
149class TGFont : public TNamed, public TRefCnt {
151friend class TGFontPool;
152friend class TGTextLayout;
155 FontStruct_t fFontStruct; // Low level graphics fontstruct
156 FontH_t fFontH; // Font handle (derived from fontstruct)
157 FontMetrics_t fFM; // Cached font metrics
158 FontAttributes_t fFA; // Actual font attributes obtained when the font was created
159 TObjString *fNamedHash; // Pointer to the named object TGFont was based on
160 Int_t fTabWidth; // Width of tabs in this font (pixels).
161 Int_t fUnderlinePos; // Offset from baseline to origin of underline bar
162 // (used for drawing underlines on a non-underlined font).
163 Int_t fUnderlineHeight; // Height of underline bar (used for drawing
164 // underlines on a non-underlined font).
165 char fTypes[256]; // Array giving types of all characters in
166 // the font, used when displaying control characters.
167 Int_t fWidths[256]; // Array giving widths of all possible characters in the font.
168 Int_t fBarHeight; // Height of underline or overstrike bar
169 // (used for simulating a native underlined or strikeout font).
172 TGFont(const char *name)
173 : TNamed(name,""), TRefCnt(), fFontStruct(0), fFontH(0), fFM(),
175 {
176 SetRefCount(1);
177 for (Int_t i=0; i<256; i++) {
178 fWidths[i] = 0;
179 fTypes[i] = ' ';
180 }
181 }
183 TGFont(const TGFont &) = delete;
184 void operator=(const TGFont &) = delete;
186 LayoutChunk_t *NewChunk(TGTextLayout *layout, int *maxPtr,
187 const char *start, int numChars,
188 int curX, int newX, int y) const;
190 virtual ~TGFont();
192 FontH_t GetFontHandle() const { return fFontH; }
194 FontStruct_t operator()() const;
195 void GetFontMetrics(FontMetrics_t *m) const;
198 Int_t PostscriptFontName(TString *dst) const;
199 Int_t TextWidth(const char *string, Int_t numChars = -1) const;
200 Int_t XTextWidth(const char *string, Int_t numChars = -1) const;
201 Int_t TextHeight() const { return fFM.fLinespace; }
203 const char *string, Int_t x, Int_t y,
204 Int_t firstChar, Int_t lastChar) const;
205 TGTextLayout *ComputeTextLayout(const char *string, Int_t numChars,
206 Int_t wrapLength, Int_t justify, Int_t flags,
207 UInt_t *width, UInt_t *height) const;
208 Int_t MeasureChars(const char *source, Int_t numChars, Int_t maxLength,
209 Int_t flags, Int_t *length) const;
210 void DrawCharsExp(Drawable_t dst, GContext_t gc, const char *source,
211 Int_t numChars, Int_t x, Int_t y) const;
212 void DrawChars(Drawable_t dst, GContext_t gc, const char *source,
213 Int_t numChars, Int_t x, Int_t y) const;
215 void Print(Option_t *option="") const;
216 virtual void SavePrimitive(std::ostream &out, Option_t * = "");
218 ClassDef(TGFont,0) // GUI font description
222struct FontStateMap_t;
223struct XLFDAttributes_t;
226class TGFontPool : public TGObject {
229 THashTable *fList; // TGFont objects pool
230 THashTable *fUidTable; // Hash table for some used string values like family names, etc.
231 THashTable *fNamedTable; // Map a name to a set of attributes for a font
233 TGFontPool(const TGFontPool& fp) = delete;
234 TGFontPool& operator=(const TGFontPool& fp) = delete;
237 const char *GetUid(const char *string);
238 Bool_t ParseXLFD(const char *string, XLFDAttributes_t *xa);
240 int FindStateNum(const FontStateMap_t *map, const char *strKey);
241 const char *FindStateString(const FontStateMap_t *map, int numKey);
242 Bool_t FieldSpecified(const char *field);
243 TGFont *GetNativeFont(const char *name, Bool_t fixedDefault = kTRUE);
244 TGFont *MakeFont(TGFont *font, FontStruct_t fontStruct, const char *fontName);
247 TGFontPool(TGClient *client);
248 virtual ~TGFontPool();
250 TGFont *GetFont(const char *font, Bool_t fixedDefault = kTRUE);
251 TGFont *GetFont(const TGFont *font);
253 TGFont *GetFont(const char *family, Int_t ptsize, Int_t weight, Int_t slant);
255 void FreeFont(const TGFont *font);
257 TGFont *FindFont(FontStruct_t font) const;
258 TGFont *FindFontByHandle(FontH_t font) const;
260 char **GetAttributeInfo(const FontAttributes_t *fa);
261 void FreeAttributeInfo(char **info);
262 char **GetFontFamilies();
263 void FreeFontFamilies(char **f);
264 Bool_t ParseFontName(const char *string, FontAttributes_t *fa);
265 const char *NameOfFont(TGFont *font);
267 void Print(Option_t *option="") const;
269 ClassDef(TGFontPool,0) // Font pool
Handle_t FontH_t
Font handle (as opposed to Font_t which is an index)
Definition GuiTypes.h:35
Handle_t Drawable_t
Drawable handle.
Definition GuiTypes.h:31
Handle_t GContext_t
Graphics context handle.
Definition GuiTypes.h:38
Handle_t FontStruct_t
Pointer to font structure.
Definition GuiTypes.h:39
#define f(i)
Definition RSha256.hxx:104
#define h(i)
Definition RSha256.hxx:106
int Int_t
Definition RtypesCore.h:45
unsigned int UInt_t
Definition RtypesCore.h:46
const Bool_t kTRUE
Definition RtypesCore.h:91
const char Option_t
Definition RtypesCore.h:66
#define ClassDef(name, id)
Definition Rtypes.h:325
#define BIT(n)
Definition Rtypes.h:85
include TDocParser_001 C image html pict1_TDocParser_001 png width
Definition TGFont.h:43
@ kFontWeightBlack
Definition TGFont.h:49
@ kFontWeightBold
Definition TGFont.h:46
@ kFontWeightNormal
Definition TGFont.h:44
@ kFontWeightDemibold
Definition TGFont.h:48
@ kFontWeightLight
Definition TGFont.h:47
@ kFontWeightUnknown
Definition TGFont.h:50
@ kFontWeightMedium
Definition TGFont.h:45
Definition TGFont.h:53
@ kFontSlantOblique
Definition TGFont.h:56
@ kFontSlantUnknown
Definition TGFont.h:57
@ kFontSlantRoman
Definition TGFont.h:54
@ kFontSlantItalic
Definition TGFont.h:55
Definition TGFont.h:35
@ kTextIgnoreTabs
Definition TGFont.h:39
@ kTextWholeWords
Definition TGFont.h:36
@ kTextPartialOK
Definition TGFont.h:38
@ kTextAtLeastOne
Definition TGFont.h:37
@ kTextIgnoreNewlines
Definition TGFont.h:40
char name[80]
Definition TGX11.cxx:110
Bool_t ParseFontName(const char *string, FontAttributes_t *fa)
Converts a string into a set of font attributes that can be used to construct a font.
Definition TGFont.cxx:1949
TGFont * GetFont(const char *font, Bool_t fixedDefault=kTRUE)
Get the specified font.
Definition TGFont.cxx:1545
const char * NameOfFont(TGFont *font)
Given a font, return a textual string identifying it.
Definition TGFont.cxx:2249
THashTable * fList
Definition TGFont.h:229
char ** GetFontFamilies()
Return information about the font families that are available on the current display.
Definition TGFont.cxx:2261
TGFontPool(const TGFontPool &fp)=delete
Bool_t ParseXLFD(const char *string, XLFDAttributes_t *xa)
Break up a fully specified XLFD into a set of font attributes.
Definition TGFont.cxx:2041
int FindStateNum(const FontStateMap_t *map, const char *strKey)
Given a lookup table, map a string to a number in the table.
Definition TGFont.cxx:2192
TGFont * GetNativeFont(const char *name, Bool_t fixedDefault=kTRUE)
The return value is a pointer to an TGFont object that represents the native font.
Definition TGFont.cxx:2554
const char * GetUid(const char *string)
Given a string, this procedure returns a unique identifier for the string.
Definition TGFont.cxx:1772
Bool_t FieldSpecified(const char *field)
Helper function for ParseXLFD().
Definition TGFont.cxx:2234
THashTable * fUidTable
Definition TGFont.h:230
TGFont * FindFontByHandle(FontH_t font) const
Find font based on its font handle. Returns 0 if font is not found.
Definition TGFont.cxx:1748
virtual ~TGFontPool()
Cleanup font pool.
Definition TGFont.cxx:1531
THashTable * fNamedTable
Definition TGFont.h:231
void FreeFont(const TGFont *font)
Free font. If ref count is 0 delete font.
Definition TGFont.cxx:1705
char ** GetAttributeInfo(const FontAttributes_t *fa)
Return information about the font attributes as an array of strings.
Definition TGFont.cxx:1792
const char * FindStateString(const FontStateMap_t *map, int numKey)
Given a lookup table, map a number to a string in the table.
Definition TGFont.cxx:2215
void FreeFontFamilies(char **f)
Delete an array of families allocated GetFontFamilies() method.
Definition TGFont.cxx:2320
TGFont * GetFontFromAttributes(FontAttributes_t *fa, TGFont *fontPtr)
Given a desired set of attributes for a font, find a font with the closest matching attributes and cr...
Definition TGFont.cxx:2343
TGFont * MakeFont(TGFont *font, FontStruct_t fontStruct, const char *fontName)
Helper for GetNativeFont() and GetFontFromAttributes().
Definition TGFont.cxx:2579
TGFont * FindFont(FontStruct_t font) const
Find font based on its font struct. Returns 0 if font is not found.
Definition TGFont.cxx:1731
void FreeAttributeInfo(char **info)
Free attributes info.
Definition TGFont.cxx:1846
TGFontPool & operator=(const TGFontPool &fp)=delete
void Print(Option_t *option="") const
List all fonts in the pool.
Definition TGFont.cxx:1863
char fTypes[256]
Definition TGFont.h:165
void GetFontMetrics(FontMetrics_t *m) const
Get font metrics.
Definition TGFont.cxx:276
void UnderlineChars(Drawable_t dst, GContext_t gc, const char *string, Int_t x, Int_t y, Int_t firstChar, Int_t lastChar) const
This procedure draws an underline for a given range of characters in a given string.
Definition TGFont.cxx:607
void DrawCharsExp(Drawable_t dst, GContext_t gc, const char *source, Int_t numChars, Int_t x, Int_t y) const
Draw a string of characters on the screen.
Definition TGFont.cxx:1450
Int_t fBarHeight
Definition TGFont.h:168
TObjString * fNamedHash
Definition TGFont.h:159
Int_t fWidths[256]
Definition TGFont.h:167
Int_t MeasureChars(const char *source, Int_t numChars, Int_t maxLength, Int_t flags, Int_t *length) const
Determine the number of characters from the string that will fit in the given horizontal span.
Definition TGFont.cxx:478
Int_t TextHeight() const
Definition TGFont.h:201
FontStruct_t GetFontStruct() const
Definition TGFont.h:193
Int_t fTabWidth
Definition TGFont.h:160
Int_t TextWidth(const char *string, Int_t numChars=-1) const
A wrapper function for the more complicated interface of MeasureChars.
Definition TGFont.cxx:565
FontH_t fFontH
Definition TGFont.h:156
Int_t fUnderlineHeight
Definition TGFont.h:163
FontStruct_t operator()() const
Not inline due to a bug in g++ 2.96 20000731 (Red Hat Linux 7.0)
Definition TGFont.cxx:290
FontAttributes_t fFA
Definition TGFont.h:158
void operator=(const TGFont &)=delete
TGFont(const TGFont &)=delete
LayoutChunk_t * NewChunk(TGTextLayout *layout, int *maxPtr, const char *start, int numChars, int curX, int newX, int y) const
Helper function for ComputeTextLayout().
Definition TGFont.cxx:1397
virtual void SavePrimitive(std::ostream &out, Option_t *="")
Save the used font as a C++ statement(s) on output stream out.
Definition TGFont.cxx:1871
FontMetrics_t fFM
Definition TGFont.h:157
TGFont(const char *name)
Definition TGFont.h:172
Int_t XTextWidth(const char *string, Int_t numChars=-1) const
Return text widht in pixels.
Definition TGFont.cxx:580
FontAttributes_t GetFontAttributes() const
Definition TGFont.h:196
TGTextLayout * ComputeTextLayout(const char *string, Int_t numChars, Int_t wrapLength, Int_t justify, Int_t flags, UInt_t *width, UInt_t *height) const
Computes the amount of screen space needed to display a multi-line, justified string of text.
Definition TGFont.cxx:651
Int_t fUnderlinePos
Definition TGFont.h:161
void Print(Option_t *option="") const
Print font info.
Definition TGFont.cxx:298
Int_t PostscriptFontName(TString *dst) const
Return the name of the corresponding Postscript font for this TGFont.
Definition TGFont.cxx:333
virtual ~TGFont()
Delete font.
Definition TGFont.cxx:266
void DrawChars(Drawable_t dst, GContext_t gc, const char *source, Int_t numChars, Int_t x, Int_t y) const
Perform a quick sanity check to ensure we won't overflow the X coordinate space.
Definition TGFont.cxx:1480
FontH_t GetFontHandle() const
Definition TGFont.h:192
FontStruct_t fFontStruct
Definition TGFont.h:155
void DrawText(Drawable_t dst, GContext_t gc, Int_t x, Int_t y, Int_t firstChar, Int_t lastChar) const
Use the information in the TGTextLayout object to display a multi-line, justified string of text.
Definition TGFont.cxx:910
Int_t PointToChar(Int_t x, Int_t y) const
Use the information in the TGTextLayout token to determine the character closest to the given point.
Definition TGFont.cxx:990
Int_t IntersectText(Int_t x, Int_t y, Int_t w, Int_t h) const
Determines whether a text layout lies entirely inside, entirely outside, or overlaps a given rectangl...
Definition TGFont.cxx:1244
const TGFont * fFont
Definition TGFont.h:120
void operator=(const TGTextLayout &tlayout)=delete
void ToPostscript(TString *dst) const
Outputs the contents of a text layout in Postscript format.
Definition TGFont.cxx:1321
Int_t fNumChunks
Definition TGFont.h:123
TGTextLayout(const TGTextLayout &tlayout)=delete
Int_t DistanceToText(Int_t x, Int_t y) const
Computes the distance in pixels from the given point to the given text layout.
Definition TGFont.cxx:1178
Int_t CharBbox(Int_t index, Int_t *x, Int_t *y, Int_t *w, Int_t *h) const
Use the information in the TGTextLayout token to return the bounding box for the character specified ...
Definition TGFont.cxx:1096
virtual ~TGTextLayout()
Definition TGFont.cxx:887
LayoutChunk_t * fChunks
Definition TGFont.h:124
Int_t fWidth
Definition TGFont.h:122
void UnderlineChar(Drawable_t dst, GContext_t gc, Int_t x, Int_t y, Int_t underline) const
Use the information in the TGTextLayout object to display an underline below an individual character.
Definition TGFont.cxx:957
const char * fString
Definition TGFont.h:121
THashTable implements a hash table to store TObject's.
Definition THashTable.h:35
The TNamed class is the base class for all named ROOT classes.
Definition TNamed.h:29
Collectable string class.
Definition TObjString.h:28
Mother of all ROOT objects.
Definition TObject.h:37
Definitions for TRefCnt, base class for reference counted objects.
Definition TRefCnt.h:27
void SetRefCount(UInt_t r)
Definition TRefCnt.h:39
Basic string class.
Definition TString.h:136
Double_t y[n]
Definition legend1.C:17
Double_t x[n]
Definition legend1.C:17
const char * fFamily
Definition TGFont.h:72
Int_t fWeight
Definition TGFont.h:74
Int_t fPointsize
Definition TGFont.h:73
FontAttributes_t & operator=(const FontAttributes_t &f)
Definition TGFont.h:95
FontAttributes_t(const FontAttributes_t &f)
Definition TGFont.h:87
Int_t fUnderline
Definition TGFont.h:76
Int_t fOverstrike
Definition TGFont.h:77
Int_t fLinespace
Definition TGFont.h:64
Int_t fMaxWidth
Definition TGFont.h:65
Bool_t fFixed
Definition TGFont.h:66
Int_t fAscent
Definition TGFont.h:62
Int_t fDescent
Definition TGFont.h:63
auto * m
Definition textangle.C:8