File indexing completed on 2024-05-12 04:33:59

 // -*- Mode: C++; c-basic-offset: 2; indent-tabs-mode: nil; c-brace-offset: 0; -*-
 // TeXFont_TFM.cpp
 //
 // Part of KDVI - A DVI previewer for the KDE desktop environment
 //
 // SPDX-FileCopyrightText: 2003 Stefan Kebekus
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <config.h>
 
 #include "TeXFont_TFM.h"
 #include "debug_dvi.h"
 
 #include <QDataStream>
 #include <QFile>
 #include <QLoggingCategory>
 
 //#define DEBUG_TFM
 
 TeXFont_TFM::TeXFont_TFM(TeXFontDefinition *parent)
     : TeXFont(parent)
 {
 #ifdef DEBUG_TFM
     qCDebug(OkularDviDebug) << "TeXFont_TFM::TeXFont_TFM( parent=" << parent << " )";
 #endif
 
     QFile file(parent->filename);
     if (!file.open(QIODevice::ReadOnly)) {
         qCCritical(OkularDviDebug) << "TeXFont_TFM::TeXFont_TFM(): Could not read TFM file";
         return;
     }
     QDataStream stream(&file);
 
     // Data from the very beginning of the TFM file, as specified in
     // "The DVI Driver Standard, Level 0", section D.2.1
     quint16 lf, lh, bc, ec, nw, nh, nd;
     stream >> lf >> lh >> bc >> ec >> nw >> nh >> nd;
 #ifdef DEBUG_TFM
     qCDebug(OkularDviDebug) << "lf= " << lf << "lh= " << lh << "\nbc= " << bc << "\nec= " << ec << "\nnw= " << nw << "\nnh= " << nh << "\nnd= " << nd;
 #endif
     if ((bc > ec) || (ec >= TeXFontDefinition::max_num_of_chars_in_font)) {
         qCCritical(OkularDviDebug) << "TeXFont_TFM::TeXFont_TFM( filename=" << parent->filename << " ): The font has an invalid bc and ec entries.";
         file.close();
         return;
     }
 
     // Data from the HEADER section of the TFM data.
     file.seek(24);
     stream >> checksum >> design_size_in_TeX_points.value;
 #ifdef DEBUG_TFM
     qCDebug(OkularDviDebug) << "checksum    = " << checksum << "design_size = " << design_size_in_TeX_points.toDouble() << " TeX Points\n"
                             << "            = " << design_size_in_TeX_points.toDouble() * 254.0 / 7227.0 << " cm";
 #endif
 
     // Width table
     fix_word widthTable_in_units_of_design_size[TeXFontDefinition::max_num_of_chars_in_font];
     for (fix_word &fw : widthTable_in_units_of_design_size) {
         fw.value = 0;
     }
 
     file.seek(24 + 4 * lh + 4 * (ec - bc));
     for (unsigned int i = 0; i < nw; i++) {
         stream >> widthTable_in_units_of_design_size[i].value;
         // Some characters, which are used as parts of glyphs, have width
         // 0 --the real width is calculated in a lig_kern program and
         // depends on the preceding character. We cannot calculate the
         // real width here and take 0.4 times the design size as an
         // approximation.
         if (widthTable_in_units_of_design_size[i].value == 0) {
             widthTable_in_units_of_design_size[i].fromDouble(0.4);
         }
     }
 
     // Height table
     fix_word heightTable_in_units_of_design_size[16];
     for (fix_word &fw : heightTable_in_units_of_design_size) {
         fw.value = 0;
     }
     for (unsigned int i = 0; i < nh; i++) {
         stream >> heightTable_in_units_of_design_size[i].value;
     }
 
     // Char-Info table
     file.seek(24 + 4 * lh);
     for (unsigned int characterCode = bc; characterCode < ec; characterCode++) {
         glyph *g = glyphtable + characterCode;
 
         quint8 byte;
         stream >> byte;
         if (byte >= nw) {
             qCCritical(OkularDviDebug) << "TeXFont_TFM::TeXFont_TFM( filename=" << parent->filename << " ): The font has an invalid Char-Info table.";
         } else {
             characterWidth_in_units_of_design_size[characterCode] = widthTable_in_units_of_design_size[byte];
             g->dvi_advance_in_units_of_design_size_by_2e20 = widthTable_in_units_of_design_size[byte].value;
         }
 
         stream >> byte;
         byte = byte >> 4;
         if (byte >= nh) {
             qCCritical(OkularDviDebug) << "TeXFont_TFM::TeXFont_TFM( filename=" << parent->filename << " ): The font has an invalid Char-Info table.";
         } else {
             characterHeight_in_units_of_design_size[characterCode] = heightTable_in_units_of_design_size[byte];
         }
 
         stream >> byte;
         stream >> byte;
     }
     file.close();
 }
 
 TeXFont_TFM::~TeXFont_TFM()
 {
 }
 
 glyph *TeXFont_TFM::getGlyph(quint16 characterCode, bool generateCharacterPixmap, const QColor &color)
 {
 #ifdef DEBUG_TFM
     qCDebug(OkularDviDebug) << "TeXFont_TFM::getGlyph( ch=" << ch << ", generateCharacterPixmap=" << generateCharacterPixmap << " )";
 #endif
 
     // Paranoia checks
     if (characterCode >= TeXFontDefinition::max_num_of_chars_in_font) {
         qCCritical(OkularDviDebug) << "TeXFont_TFM::getGlyph(): Argument is too big.";
         return glyphtable;
     }
 
     // This is the address of the glyph that will be returned.
     class glyph *g = glyphtable + characterCode;
 
     if ((generateCharacterPixmap == true) && ((g->shrunkenCharacter.isNull()) || (color != g->color))) {
         g->color = color;
         quint16 pixelWidth = (quint16)(parent->displayResolution_in_dpi * design_size_in_TeX_points.toDouble() * characterWidth_in_units_of_design_size[characterCode].toDouble() * 100.0 / 7227.0 + 0.5);
         quint16 pixelHeight = (quint16)(parent->displayResolution_in_dpi * design_size_in_TeX_points.toDouble() * characterHeight_in_units_of_design_size[characterCode].toDouble() * 100.0 / 7227.0 + 0.5);
 
         // Just make sure that weird TFM files never lead to giant
         // pixmaps that eat all system memory...
         if (pixelWidth > 50) {
             pixelWidth = 50;
         }
         if (pixelHeight > 50) {
             pixelHeight = 50;
         }
 
         g->shrunkenCharacter = QImage(pixelWidth, pixelHeight, QImage::Format_RGB32);
         g->shrunkenCharacter.fill(color.rgba());
         g->x2 = 0;
         g->y2 = pixelHeight;
     }
 
     return g;
 }