KiCad PCB EDA Suite
stroke_font.cpp
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1 /*
2  * This program source code file is part of KICAD, a free EDA CAD application.
3  *
4  * Copyright (C) 2012 Torsten Hueter, torstenhtr <at> gmx.de
5  * Copyright (C) 2013 CERN
6  * @author Maciej Suminski <maciej.suminski@cern.ch>
7  * Copyright (C) 2016 Kicad Developers, see change_log.txt for contributors.
8  *
9  * Stroke font class
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License
13  * as published by the Free Software Foundation; either version 2
14  * of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, you may find one here:
23  * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
24  * or you may search the http://www.gnu.org website for the version 2 license,
25  * or you may write to the Free Software Foundation, Inc.,
26  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
27  */
28 
29 #include <gal/stroke_font.h>
31 #include <text_utils.h>
32 #include <wx/string.h>
33 
34 
35 using namespace KIGFX;
36 
37 const double STROKE_FONT::INTERLINE_PITCH_RATIO = 1.5;
38 const double STROKE_FONT::OVERBAR_POSITION_FACTOR = 1.22;
39 const double STROKE_FONT::BOLD_FACTOR = 1.3;
40 const double STROKE_FONT::STROKE_FONT_SCALE = 1.0 / 21.0;
41 const double STROKE_FONT::ITALIC_TILT = 1.0 / 8;
42 
44  m_gal( aGal )
45 {
46 }
47 
48 
49 bool STROKE_FONT::LoadNewStrokeFont( const char* const aNewStrokeFont[], int aNewStrokeFontSize )
50 {
51  m_glyphs.clear();
52  m_glyphBoundingBoxes.clear();
53  m_glyphs.resize( aNewStrokeFontSize );
54  m_glyphBoundingBoxes.resize( aNewStrokeFontSize );
55 
56  for( int j = 0; j < aNewStrokeFontSize; j++ )
57  {
58  GLYPH glyph;
59  double glyphStartX = 0.0;
60  double glyphEndX = 0.0;
61  VECTOR2D glyphBoundingX;
62 
63  std::deque<VECTOR2D> pointList;
64 
65  int i = 0;
66 
67  while( aNewStrokeFont[j][i] )
68  {
69  VECTOR2D point( 0.0, 0.0 );
70  char coordinate[2] = { 0, };
71 
72  for( int k = 0; k < 2; k++ )
73  {
74  coordinate[k] = aNewStrokeFont[j][i + k];
75  }
76 
77  if( i < 2 )
78  {
79  // The first two values contain the width of the char
80  glyphStartX = ( coordinate[0] - 'R' ) * STROKE_FONT_SCALE;
81  glyphEndX = ( coordinate[1] - 'R' ) * STROKE_FONT_SCALE;
82  glyphBoundingX = VECTOR2D( 0, glyphEndX - glyphStartX );
83  }
84  else if( ( coordinate[0] == ' ' ) && ( coordinate[1] == 'R' ) )
85  {
86  // Raise pen
87  if( pointList.size() > 0 )
88  glyph.push_back( pointList );
89 
90  pointList.clear();
91  }
92  else
93  {
94  // In stroke font, coordinates values are coded as <value> + 'R',
95  // <value> is an ASCII char.
96  // therefore every coordinate description of the Hershey format has an offset,
97  // it has to be subtracted
98  // Note:
99  // * the stroke coordinates are stored in reduced form (-1.0 to +1.0),
100  // and the actual size is stroke coordinate * glyph size
101  // * a few shapes have a height slightly bigger than 1.0 ( like '{' '[' )
102  point.x = (double) ( coordinate[0] - 'R' ) * STROKE_FONT_SCALE - glyphStartX;
103  #define FONT_OFFSET -10
104  // FONT_OFFSET is here for historical reasons, due to the way the stroke font
105  // was built. It allows shapes coordinates like W M ... to be >= 0
106  // Only shapes like j y have coordinates < 0
107  point.y = (double) ( coordinate[1] - 'R' + FONT_OFFSET ) * STROKE_FONT_SCALE;
108  pointList.push_back( point );
109  }
110 
111  i += 2;
112  }
113 
114  if( pointList.size() > 0 )
115  glyph.push_back( pointList );
116 
117  m_glyphs[j] = glyph;
118 
119  // Compute the bounding box of the glyph
120  m_glyphBoundingBoxes[j] = computeBoundingBox( glyph, glyphBoundingX );
121  }
122 
123  return true;
124 }
125 
126 
127 // Static function:
128 double STROKE_FONT::GetInterline( double aGlyphHeight, double aGlyphThickness )
129 {
130  return ( aGlyphHeight * INTERLINE_PITCH_RATIO ) + aGlyphThickness;
131 }
132 
133 
135 {
137 }
138 
139 
140 BOX2D STROKE_FONT::computeBoundingBox( const GLYPH& aGLYPH, const VECTOR2D& aGLYPHBoundingX ) const
141 {
143 
144  std::deque<VECTOR2D> boundingPoints;
145 
146  boundingPoints.push_back( VECTOR2D( aGLYPHBoundingX.x, 0 ) );
147  boundingPoints.push_back( VECTOR2D( aGLYPHBoundingX.y, 0 ) );
148 
149  for( GLYPH::const_iterator pointListIt = aGLYPH.begin(); pointListIt != aGLYPH.end(); ++pointListIt )
150  {
151  for( std::deque<VECTOR2D>::const_iterator pointIt = pointListIt->begin();
152  pointIt != pointListIt->end(); ++pointIt )
153  {
154  boundingPoints.push_back( VECTOR2D( aGLYPHBoundingX.x, pointIt->y ) );
155  }
156  }
157 
158  boundingBox.Compute( boundingPoints );
159 
160  return boundingBox;
161 }
162 
163 
164 void STROKE_FONT::Draw( const UTF8& aText, const VECTOR2D& aPosition, double aRotationAngle )
165 {
166  if( aText.empty() )
167  return;
168 
169  // Context needs to be saved before any transformations
170  m_gal->Save();
171 
172  m_gal->Translate( aPosition );
173  m_gal->Rotate( -aRotationAngle );
174 
175  // Single line height
176  int lineHeight = getInterline( );
177  int lineCount = linesCount( aText );
178  const VECTOR2D& glyphSize = m_gal->GetGlyphSize();
179 
180  // align the 1st line of text
181  switch( m_gal->GetVerticalJustify() )
182  {
184  m_gal->Translate( VECTOR2D( 0, glyphSize.y ) );
185  break;
186 
188  m_gal->Translate( VECTOR2D( 0, glyphSize.y / 2.0 ) );
189  break;
190 
192  break;
193 
194  default:
195  break;
196  }
197 
198  if( lineCount > 1 )
199  {
200  switch( m_gal->GetVerticalJustify() )
201  {
203  break;
204 
206  m_gal->Translate( VECTOR2D(0, -( lineCount - 1 ) * lineHeight / 2) );
207  break;
208 
210  m_gal->Translate( VECTOR2D(0, -( lineCount - 1 ) * lineHeight ) );
211  break;
212  }
213  }
214 
215  m_gal->SetIsStroke( true );
216  //m_gal->SetIsFill( false );
217 
218  if( m_gal->IsFontBold() )
220 
221  // Split multiline strings into separate ones and draw them line by line
222  size_t begin = 0;
223  size_t newlinePos = aText.find( '\n' );
224 
225  while( newlinePos != aText.npos )
226  {
227  size_t length = newlinePos - begin;
228 
229  drawSingleLineText( aText.substr( begin, length ) );
230  m_gal->Translate( VECTOR2D( 0.0, lineHeight ) );
231 
232  begin = newlinePos + 1;
233  newlinePos = aText.find( '\n', begin );
234  }
235 
236  // Draw the last (or the only one) line
237  if( !aText.empty() )
238  drawSingleLineText( aText.substr( begin ) );
239 
240  m_gal->Restore();
241 }
242 
243 
245 {
246  double xOffset;
247  VECTOR2D glyphSize( m_gal->GetGlyphSize() );
248  double overbar_italic_comp = computeOverbarVerticalPosition() * ITALIC_TILT;
249 
250  if( m_gal->IsTextMirrored() )
251  overbar_italic_comp = -overbar_italic_comp;
252 
253  // Compute the text size
254  VECTOR2D textSize = computeTextLineSize( aText );
255  double half_thickness = m_gal->GetLineWidth()/2;
256 
257  // Context needs to be saved before any transformations
258  m_gal->Save();
259 
260  // First adjust: the text X position is corrected by half_thickness
261  // because when the text with thickness is draw, its full size is textSize,
262  // but the position of lines is half_thickness to textSize - half_thickness
263  // so we must translate the coordinates by half_thickness on the X axis
264  // to place the text inside the 0 to textSize X area.
265  m_gal->Translate( VECTOR2D( half_thickness, 0 ) );
266 
267  // Adjust the text position to the given horizontal justification
268  switch( m_gal->GetHorizontalJustify() )
269  {
271  m_gal->Translate( VECTOR2D( -textSize.x / 2.0, 0 ) );
272  break;
273 
275  if( !m_gal->IsTextMirrored() )
276  m_gal->Translate( VECTOR2D( -textSize.x, 0 ) );
277  break;
278 
280  if( m_gal->IsTextMirrored() )
281  m_gal->Translate( VECTOR2D( -textSize.x, 0 ) );
282  break;
283 
284  default:
285  break;
286  }
287 
288  if( m_gal->IsTextMirrored() )
289  {
290  // In case of mirrored text invert the X scale of points and their X direction
291  // (m_glyphSize.x) and start drawing from the position where text normally should end
292  // (textSize.x)
293  xOffset = textSize.x - m_gal->GetLineWidth();
294  glyphSize.x = -glyphSize.x;
295  }
296  else
297  {
298  xOffset = 0.0;
299  }
300 
301  // The overbar is indented inward at the beginning of an italicized section, but
302  // must not be indented on subsequent letters to ensure that the bar segments
303  // overlap.
304  bool last_had_overbar = false;
305  auto processedText = ProcessOverbars( aText );
306  const auto& text = processedText.first;
307  const auto& overbars = processedText.second;
308  int i = 0;
309 
310  for( UTF8::uni_iter chIt = text.ubegin(), end = text.uend(); chIt < end; ++chIt )
311  {
312  int dd = *chIt - ' ';
313 
314  if( dd >= (int) m_glyphBoundingBoxes.size() || dd < 0 )
315  dd = '?' - ' ';
316 
317  GLYPH& glyph = m_glyphs[dd];
318  BOX2D& bbox = m_glyphBoundingBoxes[dd];
319 
320  if( overbars[i] )
321  {
322  double overbar_start_x = xOffset;
323  double overbar_start_y = - computeOverbarVerticalPosition();
324  double overbar_end_x = xOffset + glyphSize.x * bbox.GetEnd().x;
325  double overbar_end_y = overbar_start_y;
326 
327  if( !last_had_overbar )
328  {
329  overbar_start_x += overbar_italic_comp;
330  last_had_overbar = true;
331  }
332 
333  VECTOR2D startOverbar( overbar_start_x, overbar_start_y );
334  VECTOR2D endOverbar( overbar_end_x, overbar_end_y );
335 
336  m_gal->DrawLine( startOverbar, endOverbar );
337  }
338  else
339  {
340  last_had_overbar = false;
341  }
342 
343  for( GLYPH::iterator pointListIt = glyph.begin(); pointListIt != glyph.end();
344  ++pointListIt )
345  {
346  std::deque<VECTOR2D> pointListScaled;
347 
348  for( std::deque<VECTOR2D>::iterator pointIt = pointListIt->begin();
349  pointIt != pointListIt->end(); ++pointIt )
350  {
351  VECTOR2D pointPos( pointIt->x * glyphSize.x + xOffset, pointIt->y * glyphSize.y );
352 
353  if( m_gal->IsFontItalic() )
354  {
355  // FIXME should be done other way - referring to the lowest Y value of point
356  // because now italic fonts are translated a bit
357  if( m_gal->IsTextMirrored() )
358  pointPos.x += pointPos.y * STROKE_FONT::ITALIC_TILT;
359  else
360  pointPos.x -= pointPos.y * STROKE_FONT::ITALIC_TILT;
361  }
362 
363  pointListScaled.push_back( pointPos );
364  }
365 
366  m_gal->DrawPolyline( pointListScaled );
367  }
368 
369  xOffset += glyphSize.x * bbox.GetEnd().x;
370  ++i;
371  }
372 
373  m_gal->Restore();
374 }
375 
376 
377 double STROKE_FONT::ComputeOverbarVerticalPosition( double aGlyphHeight, double aGlyphThickness ) const
378 {
379  // Static method.
380  // Compute the Y position of the overbar. This is the distance between
381  // the text base line and the overbar axis.
382  return aGlyphHeight * OVERBAR_POSITION_FACTOR + aGlyphThickness;
383 }
384 
385 
387 {
388  // Compute the Y position of the overbar. This is the distance between
389  // the text base line and the overbar axis.
391 }
392 
393 
395 {
397 }
398 
399 
401  double aGlyphThickness,
402  double* aTopLimit, double* aBottomLimit ) const
403 {
404  VECTOR2D string_bbox;
405  double ymax = 0.0;
406  double ymin = 0.0;
407 
408  for( UTF8::uni_iter it = aText.ubegin(), end = aText.uend(); it < end; ++it )
409  {
410  wxASSERT_MSG( *it != '\n',
411  wxT( "This function is intended to work with single line strings" ) );
412 
413  // If it is double tilda, then it is displayed as a single tilda
414  // If it is single tilda, then it is toggling overbar, so we need to skip it
415  if( *it == '~' )
416  {
417  if( ++it >= end )
418  break;
419  }
420 
421  // Index in the bounding boxes table
422  int dd = *it - ' ';
423 
424  if( dd >= (int) m_glyphBoundingBoxes.size() || dd < 0 )
425  dd = '?' - ' ';
426 
427  const BOX2D& box = m_glyphBoundingBoxes[dd];
428 
429  string_bbox.x += box.GetEnd().x;
430 
431  // Calculate Y min and Y max
432  if( aTopLimit )
433  {
434  ymax = std::max( ymax, box.GetY() );
435  ymax = std::max( ymax, box.GetEnd().y );
436  }
437 
438  if( aBottomLimit )
439  {
440  ymin = std::min( ymin, box.GetY() );
441  ymin = std::min( ymin, box.GetEnd().y );
442  }
443  }
444 
445  string_bbox.x *= aGlyphSize.x;
446  string_bbox.x += aGlyphThickness;
447  string_bbox.y = aGlyphSize.y + aGlyphThickness;
448 
449  // For italic correction, take in account italic tilt
450  if( m_gal->IsFontItalic() )
451  string_bbox.x += string_bbox.y * STROKE_FONT::ITALIC_TILT;
452 
453  if( aTopLimit )
454  *aTopLimit = ymax * aGlyphSize.y;
455 
456  if( aBottomLimit )
457  *aBottomLimit = ymin * aGlyphSize.y;
458 
459  return string_bbox;
460 }
Class UTF8 is an 8 bit string that is assuredly encoded in UTF8, and supplies special conversion supp...
Definition: utf8.h:73
virtual void DrawPolyline(const std::deque< VECTOR2D > &aPointList)
Draw a polyline.
static constexpr std::string::size_type npos
Definition: utf8.h:155
EDA_TEXT_HJUSTIFY_T GetHorizontalJustify() const
Returns current text horizontal justification setting.
coord_type GetY() const
Definition: box2.h:179
static double GetInterline(double aGlyphHeight, double aGlyphThickness)
Compute the distance (interline) between 2 lines of text (for multiline texts).
EDA_TEXT_VJUSTIFY_T GetVerticalJustify() const
Returns current text vertical justification setting.
std::pair< UTF8, std::vector< bool > > ProcessOverbars(const UTF8 &aText)
Processes a text to extract the raw text and overbar flags.
Definition: text_utils.cpp:27
double computeOverbarVerticalPosition() const
Compute the vertical position of an overbar, sometimes used in texts.
Class CAIRO_GAL is the cairo implementation of the graphics abstraction layer.
Definition: class_module.h:57
static int KiROUND(double v)
KiROUND rounds a floating point number to an int using "round halfway cases away from zero"...
Definition: common.h:107
static const double BOLD_FACTOR
Factor that determines relative line width for bold text.
Definition: stroke_font.h:193
const Vec GetEnd() const
Definition: box2.h:183
GLYPH_LIST m_glyphs
Glyph list.
Definition: stroke_font.h:131
std::string substr(size_t pos=0, size_t len=npos) const
Definition: utf8.h:182
std::vector< BOX2D > m_glyphBoundingBoxes
Bounding boxes of the glyphs.
Definition: stroke_font.h:132
void Compute(const Container &aPointList)
Compute the bounding box from a given list of points.
Definition: box2.h:79
bool LoadNewStrokeFont(const char *const aNewStrokeFont[], int aNewStrokeFontSize)
Load the new stroke font.
Definition: stroke_font.cpp:49
static const double ITALIC_TILT
Tilt factor for italic style (the is is the scaling factor on dY relative coordinates to give a tilst...
Definition: stroke_font.h:200
virtual void DrawLine(const VECTOR2D &aStartPoint, const VECTOR2D &aEndPoint)
Draw a line.
Class BOX2 handles a 2-D bounding box, built on top of an origin point and size vector, both of templated class Vec.
Definition: box2.h:41
VECTOR2D ComputeStringBoundaryLimits(const UTF8 &aText, VECTOR2D aGlyphSize, double aGlyphThickness, double *aTopLimit=NULL, double *aBottomLimit=NULL) const
Compute the boundary limits of aText (the bbox of all shapes).
uni_iter ubegin() const
Function ubegin returns a uni_iter initialized to the start of "this" UTF8 byte sequence.
Definition: utf8.h:285
virtual void Rotate(double aAngle)
Rotate the context.
BOX2I boundingBox(T aObject)
boundingBox template method
Definition: shape_index.h:59
virtual void SetLineWidth(double aLineWidth)
Set the line width.
GAL * m_gal
Pointer to the GAL.
Definition: stroke_font.h:130
bool IsFontBold() const
Returns true if current font has 'bold' attribute enabled.
VECTOR2< double > VECTOR2D
Definition: vector2d.h:588
bool empty() const
Definition: utf8.h:108
std::string::size_type find(char c) const
Definition: utf8.h:110
BOX2D computeBoundingBox(const GLYPH &aGlyph, const VECTOR2D &aGlyphBoundingX) const
Compute the bounding box of a given glyph.
VECTOR2D computeTextLineSize(const UTF8 &aText) const
Compute the X and Y size of a given text.
const VECTOR2D & GetGlyphSize() const
static const double INTERLINE_PITCH_RATIO
Factor that determines the pitch between 2 lines.
Definition: stroke_font.h:203
unsigned linesCount(const UTF8 &aText) const
Returns number of lines for a given text.
Definition: stroke_font.h:180
class uni_iter is a non-mutating iterator that walks through unicode code points in the UTF8 encoded ...
Definition: utf8.h:207
void Draw(const UTF8 &aText, const VECTOR2D &aPosition, double aRotationAngle)
Draw a string.
STROKE_FONT(GAL *aGal)
Constructor.
Definition: stroke_font.cpp:43
uni_iter uend() const
Function uend returns a uni_iter initialized to the end of "this" UTF8 byte sequence.
Definition: utf8.h:294
static const double STROKE_FONT_SCALE
Scale factor for a glyph
Definition: stroke_font.h:196
void drawSingleLineText(const UTF8 &aText)
Draws a single line of text.
virtual void Restore()
Restore the context.
#define max(a, b)
Definition: auxiliary.h:86
#define FONT_OFFSET
double ComputeOverbarVerticalPosition(double aGlyphHeight, double aGlyphThickness) const
Compute the vertical position of an overbar, sometimes used in texts.
double GetLineWidth() const
Get the line width.
static const double OVERBAR_POSITION_FACTOR
Factor that determines relative vertical position of the overbar.
Definition: stroke_font.h:190
bool IsFontItalic() const
Returns true if current font has 'italic' attribute enabled.
virtual void Save()
Save the context.
std::deque< std::deque< VECTOR2D > > GLYPH
Definition: stroke_font.h:43
bool IsTextMirrored() const
Returns true if text should displayed mirrored.
virtual void Translate(const VECTOR2D &aTranslation)
Translate the context.
virtual void SetIsStroke(bool aIsStrokeEnabled)
Enable/disable stroked outlines.
int getInterline() const
Returns a single line height using current settings.
#define min(a, b)
Definition: auxiliary.h:85
Class GAL is the abstract interface for drawing on a 2D-surface.