font.cpp

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/*
 * This program source code file is part of KICAD, a free EDA CAD application.
 *
 * Copyright (C) 2021 Ola Rinta-Koski
 * Copyright (C) 2021-2023 Kicad Developers, see AUTHORS.txt for contributors.
 *
 * Font abstract base class
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, you may find one here:
 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 * or you may search the http://www.gnu.org website for the version 2 license,
 * or you may write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
 */
 
#include <list>
#include <mutex>
#include <unordered_map>
 
#include <macros.h>
#include <string_utils.h>
#include <gal/graphics_abstraction_layer.h>
#include <font/stroke_font.h>
#include <font/outline_font.h>
#include <trigo.h>
#include <markup_parser.h>
 
// The "official" name of the Kicad stroke font (always existing)
#include <font/kicad_font_name.h>
#include <wx/tokenzr.h>
 
// markup_parser.h includes pegtl.hpp which includes windows.h... which leaks #define DrawText
#undef DrawText
 
 
using namespace KIFONT;
 
METRICS g_defaultMetrics;
 
 
const METRICS& METRICS::Default()
{
 return g_defaultMetrics;
}
 
 
FONT* FONT::s_defaultFont = nullptr;
 
std::map< std::tuple<wxString, bool, bool>, FONT*> FONT::s_fontMap;
 
class MARKUP_CACHE
{
public:
 struct ENTRY
 {
 std::string source;
 std::unique_ptr<MARKUP::NODE> root;
 };
 
 typedef std::pair<wxString, ENTRY> CACHE_ENTRY;
 
 MARKUP_CACHE( size_t aMaxSize ) :
 m_maxSize( aMaxSize )
 {
 }
 
 ENTRY& Put( const CACHE_ENTRY::first_type& aQuery, ENTRY&& aResult )
 {
 auto it = m_cache.find( aQuery );
 
 m_cacheMru.emplace_front( CACHE_ENTRY( aQuery, std::move( aResult ) ) );
 
 if( it != m_cache.end() )
 {
 m_cacheMru.erase( it->second );
 m_cache.erase( it );
 }
 
 m_cache[aQuery] = m_cacheMru.begin();
 
 if( m_cache.size() > m_maxSize )
 {
 auto last = m_cacheMru.end();
 last--;
 m_cache.erase( last->first );
 m_cacheMru.pop_back();
 }
 
 return m_cacheMru.begin()->second;
 }
 
 ENTRY* Get( const CACHE_ENTRY::first_type& aQuery )
 {
 auto it = m_cache.find( aQuery );
 
 if( it == m_cache.end() )
 return nullptr;
 
 m_cacheMru.splice( m_cacheMru.begin(), m_cacheMru, it->second );
 
 return &m_cacheMru.begin()->second;
 }
 
 void Clear()
 {
 m_cacheMru.clear();
 m_cache.clear();
 }
 
private:
 size_t m_maxSize;
 std::list<CACHE_ENTRY> m_cacheMru;
 std::unordered_map<wxString, std::list<CACHE_ENTRY>::iterator> m_cache;
};
 
 
static MARKUP_CACHE s_markupCache( 1024 );
static std::mutex s_markupCacheMutex;
 
 
FONT::FONT()
{
}
 
 
FONT* FONT::getDefaultFont()
{
 if( !s_defaultFont )
 s_defaultFont = STROKE_FONT::LoadFont( wxEmptyString );
 
 return s_defaultFont;
}
 
 
FONT* FONT::GetFont( const wxString& aFontName, bool aBold, bool aItalic )
{
 if( aFontName.empty() || aFontName.StartsWith( KICAD_FONT_NAME ) )
 return getDefaultFont();
 
 std::tuple<wxString, bool, bool> key = { aFontName, aBold, aItalic };
 
 FONT* font = nullptr;
 
 if( s_fontMap.find( key ) != s_fontMap.end() )
 font = s_fontMap[key];
 
 if( !font )
 font = OUTLINE_FONT::LoadFont( aFontName, aBold, aItalic );
 
 if( !font )
 font = getDefaultFont();
 
 s_fontMap[key] = font;
 
 return font;
}
 
 
bool FONT::IsStroke( const wxString& aFontName )
{
 // This would need a more complex implementation if we ever support more stroke fonts
 // than the KiCad Font.
 return aFontName == _( "Default Font" ) || aFontName == KICAD_FONT_NAME;
}
 
 
void FONT::getLinePositions( const wxString& aText, const VECTOR2I& aPosition,
 wxArrayString& aTextLines, std::vector<VECTOR2I>& aPositions,
 std::vector<VECTOR2I>& aExtents, const TEXT_ATTRIBUTES& aAttrs,
 const METRICS& aFontMetrics ) const
{
 wxStringSplit( aText, aTextLines, '\n' );
 int lineCount = aTextLines.Count();
 aPositions.reserve( lineCount );
 
 int interline = GetInterline( aAttrs.m_Size.y, aFontMetrics ) * aAttrs.m_LineSpacing;
 int height = 0;
 
 for( int i = 0; i < lineCount; i++ )
 {
 VECTOR2I pos( aPosition.x, aPosition.y + i * interline );
 VECTOR2I end = boundingBoxSingleLine( nullptr, aTextLines[i], pos, aAttrs.m_Size,
 aAttrs.m_Italic, aFontMetrics );
 VECTOR2I bBox( end - pos );
 
 aExtents.push_back( bBox );
 
 if( i == 0 )
 height += ( aAttrs.m_Size.y * 1.17 ); // 1.17 is a fudge to match 6.0 positioning
 else
 height += interline;
 }
 
 VECTOR2I offset( 0, 0 );
 offset.y += aAttrs.m_Size.y;
 
 if( IsStroke() )
 {
 // Fudge factors to match 6.0 positioning
 offset.x += aAttrs.m_StrokeWidth / 1.52;
 offset.y -= aAttrs.m_StrokeWidth * 0.052;
 }
 
 switch( aAttrs.m_Valign )
 {
 case GR_TEXT_V_ALIGN_TOP: break;
 case GR_TEXT_V_ALIGN_CENTER: offset.y -= height / 2; break;
 case GR_TEXT_V_ALIGN_BOTTOM: offset.y -= height; break;
 case GR_TEXT_V_ALIGN_INDETERMINATE:
 wxFAIL_MSG( wxT( "Indeterminate state legal only in dialogs." ) );
 break;
 }
 
 for( int i = 0; i < lineCount; i++ )
 {
 VECTOR2I lineSize = aExtents.at( i );
 VECTOR2I lineOffset( offset );
 
 lineOffset.y += i * interline;
 
 switch( aAttrs.m_Halign )
 {
 case GR_TEXT_H_ALIGN_LEFT: break;
 case GR_TEXT_H_ALIGN_CENTER: lineOffset.x = -lineSize.x / 2; break;
 case GR_TEXT_H_ALIGN_RIGHT: lineOffset.x = -( lineSize.x + offset.x ); break;
 case GR_TEXT_H_ALIGN_INDETERMINATE:
 wxFAIL_MSG( wxT( "Indeterminate state legal only in dialogs." ) );
 break;
 }
 
 aPositions.push_back( aPosition + lineOffset );
 }
}
 
 
void FONT::Draw( KIGFX::GAL* aGal, const wxString& aText, const VECTOR2I& aPosition,
 const VECTOR2I& aCursor, const TEXT_ATTRIBUTES& aAttrs,
 const METRICS& aFontMetrics ) const
{
 if( !aGal || aText.empty() )
 return;
 
 VECTOR2I position( aPosition - aCursor );
 
 // Split multiline strings into separate ones and draw them line by line
 wxArrayString strings_list;
 std::vector<VECTOR2I> positions;
 std::vector<VECTOR2I> extents;
 
 getLinePositions( aText, position, strings_list, positions, extents, aAttrs, aFontMetrics );
 
 aGal->SetLineWidth( aAttrs.m_StrokeWidth );
 
 for( size_t i = 0; i < strings_list.GetCount(); i++ )
 {
 drawSingleLineText( aGal, nullptr, strings_list[i], positions[i], aAttrs.m_Size,
 aAttrs.m_Angle, aAttrs.m_Mirrored, aPosition, aAttrs.m_Italic,
 aAttrs.m_Underlined, aFontMetrics );
 }
}
 
 
VECTOR2I drawMarkup( BOX2I* aBoundingBox, std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
 const MARKUP::NODE* aNode, const VECTOR2I& aPosition,
 const KIFONT::FONT* aFont, const VECTOR2I& aSize, const EDA_ANGLE& aAngle,
 bool aMirror, const VECTOR2I& aOrigin, TEXT_STYLE_FLAGS aTextStyle,
 const METRICS& aFontMetrics )
{
 VECTOR2I nextPosition = aPosition;
 bool drawUnderline = false;
 bool drawOverbar = false;
 
 if( aNode )
 {
 TEXT_STYLE_FLAGS textStyle = aTextStyle;
 
 if( !aNode->is_root() )
 {
 if( aNode->isSubscript() )
 textStyle |= TEXT_STYLE::SUBSCRIPT;
 else if( aNode->isSuperscript() )
 textStyle |= TEXT_STYLE::SUPERSCRIPT;
 
 if( aNode->isOverbar() )
 drawOverbar = true;
 
 if( aNode->has_content() )
 {
 BOX2I bbox;
 
 nextPosition = aFont->GetTextAsGlyphs( &bbox, aGlyphs, aNode->asWxString(), aSize,
 nextPosition, aAngle, aMirror, aOrigin,
 textStyle );
 
 if( aBoundingBox )
 aBoundingBox->Merge( bbox );
 }
 }
 else if( aTextStyle & TEXT_STYLE::UNDERLINE )
 {
 drawUnderline = true;
 }
 
 for( const std::unique_ptr<MARKUP::NODE>& child : aNode->children )
 {
 nextPosition = drawMarkup( aBoundingBox, aGlyphs, child.get(), nextPosition, aFont,
 aSize, aAngle, aMirror, aOrigin, textStyle, aFontMetrics );
 }
 }
 
 if( drawUnderline )
 {
 // Shorten the bar a little so its rounded ends don't make it over-long
 double barTrim = aSize.x * 0.1;
 double barOffset = aFontMetrics.GetUnderlineVerticalPosition( aSize.y );
 
 VECTOR2D barStart( aPosition.x + barTrim, aPosition.y - barOffset );
 VECTOR2D barEnd( nextPosition.x - barTrim, nextPosition.y - barOffset );
 
 if( aGlyphs )
 {
 STROKE_GLYPH barGlyph;
 
 barGlyph.AddPoint( barStart );
 barGlyph.AddPoint( barEnd );
 barGlyph.Finalize();
 
 aGlyphs->push_back( barGlyph.Transform( { 1.0, 1.0 }, { 0, 0 }, false, aAngle, aMirror,
 aOrigin ) );
 }
 }
 
 if( drawOverbar )
 {
 // Shorten the bar a little so its rounded ends don't make it over-long
 double barTrim = aSize.x * 0.1;
 double barOffset = aFontMetrics.GetOverbarVerticalPosition( aSize.y );
 
 VECTOR2D barStart( aPosition.x + barTrim, aPosition.y - barOffset );
 VECTOR2D barEnd( nextPosition.x - barTrim, nextPosition.y - barOffset );
 
 if( aGlyphs )
 {
 STROKE_GLYPH barGlyph;
 
 barGlyph.AddPoint( barStart );
 barGlyph.AddPoint( barEnd );
 barGlyph.Finalize();
 
 aGlyphs->push_back( barGlyph.Transform( { 1.0, 1.0 }, { 0, 0 }, false, aAngle, aMirror,
 aOrigin ) );
 }
 }
 
 return nextPosition;
}
 
 
VECTOR2I FONT::drawMarkup( BOX2I* aBoundingBox, std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
 const wxString& aText, const VECTOR2I& aPosition, const VECTOR2I& aSize,
 const EDA_ANGLE& aAngle, bool aMirror, const VECTOR2I& aOrigin,
 TEXT_STYLE_FLAGS aTextStyle, const METRICS& aFontMetrics ) const
{
 std::lock_guard<std::mutex> lock( s_markupCacheMutex );
 
 MARKUP_CACHE::ENTRY* markup = s_markupCache.Get( aText );
 
 if( !markup || !markup->root )
 {
 MARKUP_CACHE::ENTRY& cached = s_markupCache.Put( aText, {} );
 
 cached.source = TO_UTF8( aText );
 MARKUP::MARKUP_PARSER markupParser( &cached.source );
 cached.root = markupParser.Parse();
 markup = &cached;
 }
 
 wxASSERT( markup && markup->root );
 
 return ::drawMarkup( aBoundingBox, aGlyphs, markup->root.get(), aPosition, this, aSize, aAngle,
 aMirror, aOrigin, aTextStyle, aFontMetrics );
}
 
 
void FONT::drawSingleLineText( KIGFX::GAL* aGal, BOX2I* aBoundingBox, const wxString& aText,
 const VECTOR2I& aPosition, const VECTOR2I& aSize,
 const EDA_ANGLE& aAngle, bool aMirror, const VECTOR2I& aOrigin,
 bool aItalic, bool aUnderline, const METRICS& aFontMetrics ) const
{
 if( !aGal )
 return;
 
 TEXT_STYLE_FLAGS textStyle = 0;
 
 if( aItalic )
 textStyle |= TEXT_STYLE::ITALIC;
 
 if( aUnderline )
 textStyle |= TEXT_STYLE::UNDERLINE;
 
 std::vector<std::unique_ptr<GLYPH>> glyphs;
 
 (void) drawMarkup( aBoundingBox, &glyphs, aText, aPosition, aSize, aAngle, aMirror, aOrigin,
 textStyle, aFontMetrics );
 
 aGal->DrawGlyphs( glyphs );
}
 
 
VECTOR2I FONT::StringBoundaryLimits( const wxString& aText, const VECTOR2I& aSize, int aThickness,
 bool aBold, bool aItalic, const METRICS& aFontMetrics ) const
{
 // TODO do we need to parse every time - have we already parsed?
 BOX2I boundingBox;
 TEXT_STYLE_FLAGS textStyle = 0;
 
 if( aBold )
 textStyle |= TEXT_STYLE::BOLD;
 
 if( aItalic )
 textStyle |= TEXT_STYLE::ITALIC;
 
 (void) drawMarkup( &boundingBox, nullptr, aText, VECTOR2I(), aSize, ANGLE_0, false, VECTOR2I(),
 textStyle, aFontMetrics );
 
 if( IsStroke() )
 {
 // Inflate by a bit more than thickness/2 to catch diacriticals, descenders, etc.
 boundingBox.Inflate( KiROUND( aThickness * 1.5 ) );
 }
 else if( IsOutline() )
 {
 // Outline fonts have thickness built in, and *usually* stay within their ascent/descent
 }
 
 return boundingBox.GetSize();
}
 
 
VECTOR2I FONT::boundingBoxSingleLine( BOX2I* aBBox, const wxString& aText,
 const VECTOR2I& aPosition, const VECTOR2I& aSize,
 bool aItalic, const METRICS& aFontMetrics ) const
{
 TEXT_STYLE_FLAGS textStyle = 0;
 
 if( aItalic )
 textStyle |= TEXT_STYLE::ITALIC;
 
 VECTOR2I extents = drawMarkup( aBBox, nullptr, aText, aPosition, aSize, ANGLE_0, false,
 VECTOR2I(), textStyle, aFontMetrics );
 
 return extents;
}
 
 
/*
 * Break marked-up text into "words". In this context, a "word" is EITHER a run of marked-up
 * text (subscript, superscript or overbar), OR a run of non-marked-up text separated by spaces.
 */
void wordbreakMarkup( std::vector<std::pair<wxString, int>>* aWords,
 const std::unique_ptr<MARKUP::NODE>& aNode, const KIFONT::FONT* aFont,
 const VECTOR2I& aSize, TEXT_STYLE_FLAGS aTextStyle )
{
 TEXT_STYLE_FLAGS textStyle = aTextStyle;
 
 if( !aNode->is_root() )
 {
 wxChar escapeChar = 0;
 
 if( aNode->isSubscript() )
 {
 escapeChar = '_';
 textStyle = TEXT_STYLE::SUBSCRIPT;
 }
 else if( aNode->isSuperscript() )
 {
 escapeChar = '^';
 textStyle = TEXT_STYLE::SUPERSCRIPT;
 }
 
 if( aNode->isOverbar() )
 {
 escapeChar = '~';
 textStyle |= TEXT_STYLE::OVERBAR;
 }
 
 if( escapeChar )
 {
 wxString word = wxString::Format( wxT( "%c{" ), escapeChar );
 int width = 0;
 
 if( aNode->has_content() )
 {
 VECTOR2I next = aFont->GetTextAsGlyphs( nullptr, nullptr, aNode->asWxString(),
 aSize, { 0, 0 }, ANGLE_0, false, { 0, 0 },
 textStyle );
 word += aNode->asWxString();
 width += next.x;
 }
 
 std::vector<std::pair<wxString, int>> childWords;
 
 for( const std::unique_ptr<MARKUP::NODE>& child : aNode->children )
 wordbreakMarkup( &childWords, child, aFont, aSize, textStyle );
 
 for( const std::pair<wxString, int>& childWord : childWords )
 {
 word += childWord.first;
 width += childWord.second;
 }
 
 word += wxT( "}" );
 aWords->emplace_back( std::make_pair( word, width ) );
 return;
 }
 else
 {
 wxString textRun = aNode->asWxString();
 wxStringTokenizer tokenizer( textRun, " ", wxTOKEN_RET_DELIMS );
 std::vector<wxString> words;
 
 while( tokenizer.HasMoreTokens() )
 words.emplace_back( tokenizer.GetNextToken() );
 
 for( const wxString& word : words )
 {
 wxString chars = word;
 chars.Trim();
 
 int w = aFont->GetTextAsGlyphs( nullptr, nullptr, chars, aSize, { 0, 0 },
 ANGLE_0, false, { 0, 0 }, textStyle ).x;
 
 aWords->emplace_back( std::make_pair( word, w ) );
 }
 }
 }
 
 for( const std::unique_ptr<MARKUP::NODE>& child : aNode->children )
 wordbreakMarkup( aWords, child, aFont, aSize, textStyle );
}
 
 
void FONT::wordbreakMarkup( std::vector<std::pair<wxString, int>>* aWords, const wxString& aText,
 const VECTOR2I& aSize, TEXT_STYLE_FLAGS aTextStyle ) const
{
 MARKUP::MARKUP_PARSER markupParser( TO_UTF8( aText ) );
 std::unique_ptr<MARKUP::NODE> root = markupParser.Parse();
 
 ::wordbreakMarkup( aWords, root, this, aSize, aTextStyle );
}
 
 
/*
 * This is a highly simplified line-breaker. KiCad is an EDA tool, not a word processor.
 *
 * 1) It breaks only on spaces. If you type a word wider than the column width then you get
 * overflow.
 * 2) It treats runs of formatted text (superscript, subscript, overbar) as single words.
 * 3) It does not perform justification.
 *
 * The results of the linebreaking are the addition of \n in the text. It is presumed that this
 * function is called on m_shownText (or equivalent) rather than the original source text.
 */
void FONT::LinebreakText( wxString& aText, int aColumnWidth, const VECTOR2I& aSize, int aThickness,
 bool aBold, bool aItalic ) const
{
 TEXT_STYLE_FLAGS textStyle = 0;
 
 if( aBold )
 textStyle |= TEXT_STYLE::BOLD;
 
 if( aItalic )
 textStyle |= TEXT_STYLE::ITALIC;
 
 int spaceWidth = GetTextAsGlyphs( nullptr, nullptr, wxS( " " ), aSize, VECTOR2I(), ANGLE_0,
 false, VECTOR2I(), textStyle ).x;
 
 wxArrayString textLines;
 wxStringSplit( aText, textLines, '\n' );
 
 aText = wxEmptyString;
 
 for( size_t ii = 0; ii < textLines.Count(); ++ii )
 {
 std::vector<std::pair<wxString, int>> markup;
 std::vector<std::pair<wxString, int>> words;
 
 wordbreakMarkup( &markup, textLines[ii], aSize, textStyle );
 
 for( const auto& [ run, runWidth ] : markup )
 {
 if( !words.empty() && !words.back().first.EndsWith( ' ' ) )
 {
 words.back().first += run;
 words.back().second += runWidth;
 }
 else
 {
 words.emplace_back( std::make_pair( run, runWidth ) );
 }
 }
 
 bool buryMode = false;
 int lineWidth = 0;
 wxString pendingSpaces;
 
 for( const auto& [ word, wordWidth ] : words )
 {
 int pendingSpaceWidth = (int) pendingSpaces.Length() * spaceWidth;
 bool overflow = lineWidth + pendingSpaceWidth + wordWidth > aColumnWidth - aThickness;
 
 if( overflow && pendingSpaces.Length() > 0 )
 {
 aText += '\n';
 lineWidth = 0;
 pendingSpaces = wxEmptyString;
 pendingSpaceWidth = 0;
 buryMode = true;
 }
 
 if( word == wxS( " " ) )
 {
 pendingSpaces += word;
 }
 else
 {
 if( buryMode )
 {
 buryMode = false;
 }
 else
 {
 aText += pendingSpaces;
 lineWidth += pendingSpaceWidth;
 }
 
 if( word.EndsWith( ' ' ) )
 {
 aText += word.Left( word.Length() - 1 );
 pendingSpaces = wxS( " " );
 }
 else
 {
 aText += word;
 pendingSpaces = wxEmptyString;
 }
 
 lineWidth += wordWidth;
 }
 }
 
 // Add the newlines back onto the string
 if( ii != ( textLines.Count() - 1 ) )
 aText += '\n';
 }
}