kicad/common/font/outline_font.cpp

569 lines
18 KiB
C++

/*
* This program source code file is part of KICAD, a free EDA CAD application.
*
* Copyright (C) 2021 Ola Rinta-Koski <gitlab@rinta-koski.net>
* Copyright (C) 2021-2022 Kicad Developers, see AUTHORS.txt for contributors.
*
* Outline font 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 <limits>
#include <pgm_base.h>
#include <settings/settings_manager.h>
#include <harfbuzz/hb.h>
#include <harfbuzz/hb-ft.h>
#include <bezier_curves.h>
#include <geometry/shape_poly_set.h>
#include <eda_text.h>
#include <font/outline_font.h>
#include FT_GLYPH_H
#include FT_BBOX_H
#include <trigo.h>
#include <font/fontconfig.h>
#include <convert_basic_shapes_to_polygon.h>
using namespace KIFONT;
FT_Library OUTLINE_FONT::m_freeType = nullptr;
OUTLINE_FONT::OUTLINE_FONT() :
m_face(NULL),
m_faceSize( 16 )
{
if( !m_freeType )
FT_Init_FreeType( &m_freeType );
}
wxString OUTLINE_FONT::FreeTypeVersion()
{
if( !m_freeType )
FT_Init_FreeType( &m_freeType );
FT_Int major = 0;
FT_Int minor = 0;
FT_Int patch = 0;
FT_Library_Version( m_freeType, &major, &minor, &patch );
return wxString::Format( "%d.%d.%d", major, minor, patch );
}
wxString OUTLINE_FONT::HarfBuzzVersion()
{
return wxString::FromUTF8( HB_VERSION_STRING );
}
wxString OUTLINE_FONT::FontConfigVersion()
{
return fontconfig::FONTCONFIG::Version();
}
wxString OUTLINE_FONT::FontLibraryVersion()
{
return wxString::Format( "FreeType %s HarfBuzz %s", FreeTypeVersion(), HarfBuzzVersion() );
}
OUTLINE_FONT* OUTLINE_FONT::LoadFont( const wxString& aFontName, bool aBold, bool aItalic )
{
OUTLINE_FONT* font = new OUTLINE_FONT();
wxString fontFile;
wxString qualifiedFontName = aFontName;
if( aBold )
qualifiedFontName << wxS( ":Bold" );
if( aItalic )
qualifiedFontName << wxS( ":Italic" );
if( Fontconfig()->FindFont( qualifiedFontName, fontFile ) )
(void) font->loadFace( fontFile );
font->m_fontName = aFontName; // Keep asked-for name, even if we substituted.
font->m_fontFileName = fontFile;
return font;
}
FT_Error OUTLINE_FONT::loadFace( const wxString& aFontFileName )
{
// TODO: check that going from wxString to char* with UTF-8
// conversion for filename makes sense on any/all platforms
FT_Error e = FT_New_Face( m_freeType, aFontFileName.mb_str( wxConvUTF8 ), 0, &m_face );
if( !e )
{
FT_Select_Charmap( m_face, FT_Encoding::FT_ENCODING_UNICODE );
// params:
// m_face = handle to face object
// 0 = char width in 1/64th of points ( 0 = same as char height )
// faceSize() = char height in 1/64th of points
// GLYPH_RESOLUTION = horizontal device resolution (288dpi, 4x default)
// 0 = vertical device resolution ( 0 = same as horizontal )
FT_Set_Char_Size( m_face, 0, faceSize(), GLYPH_RESOLUTION, 0 );
}
return e;
}
/**
* Compute the vertical position of an overbar. This is the distance between the text
* baseline and the overbar.
*/
double OUTLINE_FONT::ComputeOverbarVerticalPosition( double aGlyphHeight ) const
{
// The overbar on actual text is positioned above the bounding box of the glyphs. However,
// that's expensive to calculate so we use an estimation here (as this is only used for
// calculating bounding boxes).
return aGlyphHeight * m_outlineFontSizeCompensation;
}
/**
* Compute the vertical position of an underline. This is the distance between the text
* baseline and the underline.
*/
double OUTLINE_FONT::ComputeUnderlineVerticalPosition( double aGlyphHeight ) const
{
return aGlyphHeight * m_underlineOffsetScaler;
}
/**
* Compute the distance (interline) between 2 lines of text (for multiline texts). This is
* the distance between baselines, not the space between line bounding boxes.
*/
double OUTLINE_FONT::GetInterline( double aGlyphHeight, double aLineSpacing ) const
{
double pitch = INTERLINE_PITCH_RATIO;
if( GetFace()->units_per_EM )
pitch = GetFace()->height / GetFace()->units_per_EM;
double interline = aLineSpacing * aGlyphHeight * pitch * m_outlineFontSizeCompensation;
// FONT TODO this hack is an attempt to fix interline spacing by eyeballing it
static constexpr double interlineHackMultiplier = 1.2;
interline *= interlineHackMultiplier;
return interline;
}
static bool contourIsFilled( const CONTOUR& c )
{
switch( c.m_Orientation )
{
case FT_ORIENTATION_TRUETYPE: return c.m_Winding == 1;
case FT_ORIENTATION_POSTSCRIPT: return c.m_Winding == -1;
default: return false;
}
}
static bool contourIsHole( const CONTOUR& c )
{
return !contourIsFilled( c );
}
BOX2I OUTLINE_FONT::getBoundingBox( const std::vector<std::unique_ptr<GLYPH>>& aGlyphs ) const
{
int minX = INT_MAX;
int minY = INT_MAX;
int maxX = INT_MIN;
int maxY = INT_MIN;
for( const std::unique_ptr<KIFONT::GLYPH>& glyph : aGlyphs )
{
BOX2D bbox = glyph->BoundingBox();
bbox.Normalize();
if( minX > bbox.GetX() )
minX = bbox.GetX();
if( minY > bbox.GetY() )
minY = bbox.GetY();
if( maxX < bbox.GetRight() )
maxX = bbox.GetRight();
if( maxY < bbox.GetBottom() )
maxY = bbox.GetBottom();
}
BOX2I ret;
ret.SetOrigin( minX, minY );
ret.SetEnd( maxX, maxY );
return ret;
}
void OUTLINE_FONT::GetLinesAsGlyphs( std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
const wxString& aText, const VECTOR2I& aPosition,
const TEXT_ATTRIBUTES& aAttrs ) const
{
wxArrayString strings;
std::vector<VECTOR2I> positions;
std::vector<VECTOR2I> extents;
TEXT_STYLE_FLAGS textStyle = 0;
if( aAttrs.m_Italic )
textStyle |= TEXT_STYLE::ITALIC;
getLinePositions( aText, aPosition, strings, positions, extents, aAttrs );
for( size_t i = 0; i < strings.GetCount(); i++ )
{
(void) drawMarkup( nullptr, aGlyphs, strings.Item( i ), positions[i], aAttrs.m_Size,
aAttrs.m_Angle, aAttrs.m_Mirrored, aPosition, textStyle );
}
}
VECTOR2I OUTLINE_FONT::GetTextAsGlyphs( BOX2I* aBBox, std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
const wxString& aText, const VECTOR2I& aSize,
const VECTOR2I& aPosition, const EDA_ANGLE& aAngle,
bool aMirror, const VECTOR2I& aOrigin,
TEXT_STYLE_FLAGS aTextStyle ) const
{
// HarfBuzz needs further processing to split tab-delimited text into text runs.
constexpr double TAB_WIDTH = 4 * 0.6;
VECTOR2I position = aPosition;
wxString textRun;
if( aBBox )
{
aBBox->SetOrigin( aPosition );
aBBox->SetEnd( aPosition );
}
for( wxUniChar c : aText )
{
// Handle tabs as locked to the nearest 4th column (in space-widths).
if( c == '\t' )
{
if( !textRun.IsEmpty() )
{
position = getTextAsGlyphs( aBBox, aGlyphs, textRun, aSize, position, aAngle,
aMirror, aOrigin, aTextStyle );
textRun.clear();
}
int tabWidth = KiROUND( aSize.x * TAB_WIDTH );
int currentIntrusion = ( position.x - aOrigin.x ) % tabWidth;
position.x += tabWidth - currentIntrusion;
}
else
{
textRun += c;
}
}
if( !textRun.IsEmpty() )
{
position = getTextAsGlyphs( aBBox, aGlyphs, textRun, aSize, position, aAngle, aMirror,
aOrigin, aTextStyle );
}
return position;
}
double OUTLINE_FONT::getOverbarOffset( int ascender, int height, int thickness ) const
{
double thicknessRatio = abs( (double) thickness ) / (double) height;
double ascenderRatio = (double) ascender / (double) height;
if( thicknessRatio < 0.05 )
return 0.04;
else if( ascenderRatio < 0.78 )
return 0.00;
else if( ascenderRatio < 0.80 )
return -0.03;
else
return -0.06;
}
VECTOR2I OUTLINE_FONT::getTextAsGlyphs( BOX2I* aBBox, std::vector<std::unique_ptr<GLYPH>>* aGlyphs,
const wxString& aText, const VECTOR2I& aSize,
const VECTOR2I& aPosition, const EDA_ANGLE& aAngle,
bool aMirror, const VECTOR2I& aOrigin,
TEXT_STYLE_FLAGS aTextStyle ) const
{
VECTOR2D glyphSize = aSize;
FT_Face face = m_face;
double scaler = faceSize();
if( IsSubscript( aTextStyle ) || IsSuperscript( aTextStyle ) )
{
scaler = subscriptSize();
}
// set glyph resolution so that FT_Load_Glyph() results are good enough for decomposing
FT_Set_Char_Size( face, 0, scaler, GLYPH_RESOLUTION, 0 );
hb_buffer_t* buf = hb_buffer_create();
hb_buffer_add_utf8( buf, UTF8( aText ).c_str(), -1, 0, -1 );
hb_buffer_guess_segment_properties( buf ); // guess direction, script, and language based on
// contents
unsigned int glyphCount;
hb_glyph_info_t* glyphInfo = hb_buffer_get_glyph_infos( buf, &glyphCount );
hb_glyph_position_t* glyphPos = hb_buffer_get_glyph_positions( buf, &glyphCount );
hb_font_t* referencedFont = hb_ft_font_create_referenced( face );
hb_ft_font_set_funcs( referencedFont );
hb_shape( referencedFont, buf, nullptr, 0 );
VECTOR2D scaleFactor( glyphSize.x / faceSize(), -glyphSize.y / faceSize() );
scaleFactor = scaleFactor * m_outlineFontSizeCompensation;
VECTOR2I cursor( 0, 0 );
for( unsigned int i = 0; i < glyphCount; i++ )
{
// Don't process glyphs that were already included in a previous cluster
if( i > 0 && glyphInfo[i].cluster == glyphInfo[i-1].cluster )
continue;
if( aGlyphs )
{
FT_Load_Glyph( face, glyphInfo[i].codepoint, FT_LOAD_NO_BITMAP );
// contours is a collection of all outlines in the glyph; for example the 'o' glyph
// generally contains 2 contours, one for the glyph outline and one for the hole
CONTOURS contours;
OUTLINE_DECOMPOSER decomposer( face->glyph->outline );
decomposer.OutlineToSegments( &contours );
std::unique_ptr<OUTLINE_GLYPH> glyph = std::make_unique<OUTLINE_GLYPH>();
std::vector<SHAPE_LINE_CHAIN> holes;
for( CONTOUR& c : contours )
{
GLYPH_POINTS points = c.m_Points;
SHAPE_LINE_CHAIN shape;
for( const VECTOR2D& v : points )
{
VECTOR2D pt( v + cursor );
if( IsSubscript( aTextStyle ) )
pt.y += m_subscriptVerticalOffset * scaler;
else if( IsSuperscript( aTextStyle ) )
pt.y += m_superscriptVerticalOffset * scaler;
pt *= scaleFactor;
pt += aPosition;
if( aMirror )
pt.x = aOrigin.x - ( pt.x - aOrigin.x );
if( !aAngle.IsZero() )
RotatePoint( pt, aOrigin, aAngle );
shape.Append( pt.x, pt.y );
}
shape.SetClosed( true );
if( contourIsHole( c ) )
holes.push_back( std::move( shape ) );
else
glyph->AddOutline( std::move( shape ) );
}
for( SHAPE_LINE_CHAIN& hole : holes )
{
if( hole.PointCount() )
{
for( int ii = 0; ii < glyph->OutlineCount(); ++ii )
{
if( glyph->Outline( ii ).PointInside( hole.GetPoint( 0 ) ) )
{
glyph->AddHole( std::move( hole ), ii );
break;
}
}
}
}
// FONT TODO we might not want to do Fracture() here;
// knockout text (eg. silkscreen labels with a background) will
// need to do that after the contours have been turned into holes
// and vice versa
if( glyph->HasHoles() )
glyph->Fracture( SHAPE_POLY_SET::PM_FAST ); // FONT TODO verify aFastMode
aGlyphs->push_back( std::move( glyph ) );
}
hb_glyph_position_t& pos = glyphPos[i];
cursor.x += ( pos.x_advance * GLYPH_SIZE_SCALER );
cursor.y += ( pos.y_advance * GLYPH_SIZE_SCALER );
}
int ascender = abs( face->size->metrics.ascender * GLYPH_SIZE_SCALER );
int height = abs( face->size->metrics.height * GLYPH_SIZE_SCALER );
int descender = abs( face->size->metrics.descender * GLYPH_SIZE_SCALER );
VECTOR2I extents( cursor.x * scaleFactor.x, ( ascender + descender ) * abs( scaleFactor.y ) );
// Font metrics don't include all descenders and diacriticals, so beef them up just a little.
extents.y *= 1.05;
if( IsOverbar( aTextStyle ) )
{
std::vector<std::unique_ptr<GLYPH>> underscoreGlyphs;
getTextAsGlyphs( nullptr, &underscoreGlyphs, wxT( "_" ), aSize, { 0, 0 }, ANGLE_0, false,
{ 0, 0 }, aTextStyle & ~TEXT_STYLE::OVERBAR );
OUTLINE_GLYPH* underscoreGlyph = static_cast<OUTLINE_GLYPH*>( underscoreGlyphs[0].get() );
BOX2I underscoreBBox;
for( const VECTOR2I& pt : underscoreGlyph->Outline( 0 ).CPoints() )
underscoreBBox.Merge( pt );
int barThickness = underscoreBBox.GetHeight();
// Shorten the bar a little so its rounded ends don't make it over-long
double barTrim = barThickness / 2.0;
double barOffset = getOverbarOffset( ascender, height, barThickness / scaleFactor.y );
VECTOR2I topLeft( aPosition );
VECTOR2I topRight( aPosition );
topLeft.y += ascender * scaleFactor.y * ( 1.0 + barOffset );
topRight.y = topLeft.y;
topLeft.x += barTrim;
topRight.x += extents.x - barTrim;
extents.y *= ( 1.0 + barOffset + barOffset );
extents.x += barTrim;
if( IsItalic() )
{
topLeft.x += aSize.y * ITALIC_TILT;
topRight.x += aSize.y * ITALIC_TILT;
extents.x += aSize.y * ITALIC_TILT;
}
if( aMirror )
{
topLeft.x = aOrigin.x - ( topLeft.x - aOrigin.x );
topRight.x = aOrigin.x - ( topRight.x - aOrigin.x );
}
if( !aAngle.IsZero() )
{
RotatePoint( topLeft, aOrigin, aAngle );
RotatePoint( topRight, aOrigin, aAngle );
}
if( aGlyphs )
{
int maxError = KiROUND( barThickness / 48 );
SHAPE_POLY_SET poly;
TransformOvalToPolygon( poly, topLeft, topRight, barThickness, maxError, ERROR_INSIDE );
std::unique_ptr<OUTLINE_GLYPH> overbarGlyph = std::make_unique<OUTLINE_GLYPH>( poly );
aGlyphs->push_back( std::move( overbarGlyph ) );
}
}
hb_buffer_destroy( buf );
hb_font_destroy( referencedFont );
VECTOR2I cursorDisplacement( cursor.x * scaleFactor.x, -cursor.y * scaleFactor.y );
if( aBBox )
aBBox->Merge( aPosition + extents );
return VECTOR2I( aPosition.x + cursorDisplacement.x, aPosition.y + cursorDisplacement.y );
}
#undef OUTLINEFONT_RENDER_AS_PIXELS
#ifdef OUTLINEFONT_RENDER_AS_PIXELS
/*
* WIP: eeschema (and PDF output?) should use pixel rendering instead of linear segmentation
*/
void OUTLINE_FONT::RenderToOpenGLCanvas( KIGFX::OPENGL_GAL& aGal, const wxString& aString,
const VECTOR2D& aGlyphSize, const VECTOR2I& aPosition,
const EDA_ANGLE& aOrientation, bool aIsMirrored ) const
{
hb_buffer_t* buf = hb_buffer_create();
hb_buffer_add_utf8( buf, UTF8( aString ).c_str(), -1, 0, -1 );
hb_buffer_guess_segment_properties( buf ); // guess direction, script, and language based on contents
unsigned int glyphCount;
hb_glyph_info_t* glyphInfo = hb_buffer_get_glyph_infos( buf, &glyphCount );
hb_glyph_position_t* glyphPos = hb_buffer_get_glyph_positions( buf, &glyphCount );
hb_font_t* referencedFont = hb_ft_font_create_referenced( m_face );
hb_ft_font_set_funcs( referencedFont );
hb_shape( referencedFont, buf, nullptr, 0 );
const double mirror_factor = ( aIsMirrored ? 1 : -1 );
const double x_scaleFactor = mirror_factor * aGlyphSize.x / mScaler;
const double y_scaleFactor = aGlyphSize.y / mScaler;
hb_position_t cursor_x = 0;
hb_position_t cursor_y = 0;
for( unsigned int i = 0; i < glyphCount; i++ )
{
hb_glyph_position_t& pos = glyphPos[i];
int codepoint = glyphInfo[i].codepoint;
FT_Error e = FT_Load_Glyph( m_face, codepoint, FT_LOAD_DEFAULT );
// TODO handle FT_Load_Glyph error
FT_Glyph glyph;
e = FT_Get_Glyph( m_face->glyph, &glyph );
// TODO handle FT_Get_Glyph error
wxPoint pt( aPosition );
pt.x += ( cursor_x >> 6 ) * x_scaleFactor;
pt.y += ( cursor_y >> 6 ) * y_scaleFactor;
cursor_x += pos.x_advance;
cursor_y += pos.y_advance;
}
hb_buffer_destroy( buf );
}
#endif //OUTLINEFONT_RENDER_AS_PIXELS