font_win32.cpp

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/*
 * This file is part of OpenTTD.
 * OpenTTD 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, version 2.
 * OpenTTD 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 OpenTTD. If not, see <https://www.gnu.org/licenses/old-licenses/gpl-2.0>.
 */

 
#include "../../stdafx.h"
#include "../../debug.h"
#include "../../blitter/factory.hpp"
#include "../../core/math_func.hpp"
#include "../../error_func.h"
#include "../../fileio_func.h"
#include "../../fontcache.h"
#include "../../fontcache/truetypefontcache.h"
#include "../../library_loader.h"
#include "../../string_func.h"
#include "../../strings_func.h"
#include "../../zoom_func.h"
#include "font_win32.h"
 
#include "../../table/control_codes.h"
 
#include <windows.h>
#include <shlobj.h> /* SHGetFolderPath */
#include "win32.h"
#undef small // Say what, Windows?
 
#include "../../safeguards.h"
 
struct EFCParam {
  LOCALESIGNATURE  locale;
  MissingGlyphSearcher *callback;
  std::vector<std::wstring> fonts;
 
  bool Add(const std::wstring_view &font)
  {
    auto it = std::ranges::find(this->fonts, font);
    if (it != std::end(this->fonts)) return false;
 
    this->fonts.emplace_back(font);
 
    return true;
  }
};
 
static int CALLBACK EnumFontCallback(const ENUMLOGFONTEX *logfont, const NEWTEXTMETRICEX *metric, DWORD type, LPARAM lParam)
{
  EFCParam *info = (EFCParam *)lParam;
 
  /* Skip duplicates */
  if (!info->Add(logfont->elfFullName)) return 1;
  /* Only use TrueType fonts */
  if (!(type & TRUETYPE_FONTTYPE)) return 1;
  /* Don't use SYMBOL fonts */
  if (logfont->elfLogFont.lfCharSet == SYMBOL_CHARSET) return 1;
  /* Use monospaced fonts when asked for it. */
  if (info->callback->missing_fontsizes.Test(FontSize::Monospace) && (logfont->elfLogFont.lfPitchAndFamily & (FF_MODERN | FIXED_PITCH)) != (FF_MODERN | FIXED_PITCH)) return 1;
 
  /* The font has to have at least one of the supported locales to be usable. */
  auto check_bitfields = [&]() {
    /* First try Unicode Subset Bitfield. */
    for (uint8_t i = 0; i < 4; i++) {
      if ((metric->ntmFontSig.fsUsb[i] & info->locale.lsUsb[i]) != 0) return true;
    }
    /* Keep Code Page Bitfield as a fallback. */
    for (uint8_t i = 0; i < 2; i++) {
      if ((metric->ntmFontSig.fsCsb[i] & info->locale.lsCsbSupported[i]) != 0) return true;
    }
    return false;
  };
  if (!check_bitfields()) return 1;
 
  char font_name[MAX_PATH];
  convert_from_fs(logfont->elfFullName, font_name);
 
  if (!FontCache::TryFallback(info->callback->missing_fontsizes, info->callback->missing_glyphs, font_name, logfont->elfLogFont)) return 1;
 
  FontCache::AddFallback(info->callback->missing_fontsizes, font_name, logfont->elfLogFont);
  Debug(fontcache, 1, "Fallback font: {}", font_name);
  return 0; // stop enumerating
}

Win32FontCache::Win32FontCache(FontSize fs, const LOGFONT &logfont, int pixels) : TrueTypeFontCache(fs, pixels), logfont(logfont)
{
  this->dc = CreateCompatibleDC(nullptr);
  this->SetFontSize(pixels);
}

Win32FontCache::~Win32FontCache()
{
  this->ClearFontCache();
  DeleteDC(this->dc);
  DeleteObject(this->font);
}
 
void Win32FontCache::SetFontSize(int pixels)
{
  if (pixels == 0) {
    /* Try to determine a good height based on the minimal height recommended by the font. */
    int scaled_height = ScaleGUITrad(FontCache::GetDefaultFontHeight(this->fs));
    pixels = scaled_height;
 
    HFONT temp = CreateFontIndirect(&this->logfont);
    if (temp != nullptr) {
      HGDIOBJ old = SelectObject(this->dc, temp);
 
      UINT size = GetOutlineTextMetrics(this->dc, 0, nullptr);
      LPOUTLINETEXTMETRIC otm = (LPOUTLINETEXTMETRIC)new BYTE[size];
      GetOutlineTextMetrics(this->dc, size, otm);
 
      /* Font height is minimum height plus the difference between the default
       * height for this font size and the small size. */
      int diff = scaled_height - ScaleGUITrad(FontCache::GetDefaultFontHeight(FontSize::Small));
      /* Clamp() is not used as scaled_height could be greater than MAX_FONT_SIZE, which is not permitted in Clamp(). */
      pixels = std::min(std::max(std::min<int>(otm->otmusMinimumPPEM, MAX_FONT_MIN_REC_SIZE) + diff, scaled_height), MAX_FONT_SIZE);
 
      delete[] (BYTE*)otm;
      SelectObject(dc, old);
      DeleteObject(temp);
    }
  } else {
    pixels = ScaleGUITrad(pixels);
  }
  this->used_size = pixels;
 
  /* Create GDI font handle. */
  this->logfont.lfHeight = -pixels;
  this->logfont.lfWidth = 0;
  this->logfont.lfOutPrecision = OUT_TT_ONLY_PRECIS;
  this->logfont.lfQuality = ANTIALIASED_QUALITY;
 
  if (this->font != nullptr) {
    SelectObject(dc, this->old_font);
    DeleteObject(this->font);
  }
  this->font = CreateFontIndirect(&this->logfont);
  this->old_font = SelectObject(this->dc, this->font);
 
  /* Query the font metrics we needed. */
  UINT otmSize = GetOutlineTextMetrics(this->dc, 0, nullptr);
  POUTLINETEXTMETRIC otm = (POUTLINETEXTMETRIC)new BYTE[otmSize];
  GetOutlineTextMetrics(this->dc, otmSize, otm);
 
  this->ascender = otm->otmTextMetrics.tmAscent;
  this->descender = otm->otmTextMetrics.tmDescent;
  this->height = this->ascender + this->descender;
  this->glyph_size.cx = otm->otmTextMetrics.tmMaxCharWidth;
  this->glyph_size.cy = otm->otmTextMetrics.tmHeight;
 
  this->fontname = FS2OTTD((LPWSTR)((BYTE *)otm + (ptrdiff_t)otm->otmpFaceName));
 
  Debug(fontcache, 2, "Loaded font '{}' with size {}", this->fontname, pixels);
  delete[] (BYTE*)otm;
}

void Win32FontCache::ClearFontCache()
{
  /* GUI scaling might have changed, determine font size anew if it was automatically selected. */
  if (this->font != nullptr) this->SetFontSize(this->req_size);
 
  this->TrueTypeFontCache::ClearFontCache();
}
 
/* virtual */ const Sprite *Win32FontCache::InternalGetGlyph(GlyphID key, bool aa)
{
  GLYPHMETRICS gm;
  MAT2 mat = { {0, 1}, {0, 0}, {0, 0}, {0, 1} };
 
  /* Call GetGlyphOutline with zero size initially to get required memory size. */
  DWORD size = GetGlyphOutline(this->dc, key, GGO_GLYPH_INDEX | (aa ? GGO_GRAY8_BITMAP : GGO_BITMAP), &gm, 0, nullptr, &mat);
  if (size == GDI_ERROR) UserError("Unable to render font glyph");
 
  /* Add 1 scaled pixel for the shadow on the medium font. Our sprite must be at least 1x1 pixel. */
  uint shadow = (this->fs == FontSize::Normal) ? ScaleGUITrad(1) : 0;
  uint width = std::max(1U, (uint)gm.gmBlackBoxX + shadow);
  uint height = std::max(1U, (uint)gm.gmBlackBoxY + shadow);
 
  /* Limit glyph size to prevent overflows later on. */
  if (width > MAX_GLYPH_DIM || height > MAX_GLYPH_DIM) UserError("Font glyph is too large");
 
  /* Call GetGlyphOutline again with size to actually render the glyph. */
  uint8_t *bmp = this->render_buffer.Allocate(size);
  GetGlyphOutline(this->dc, key, GGO_GLYPH_INDEX | (aa ? GGO_GRAY8_BITMAP : GGO_BITMAP), &gm, size, bmp, &mat);
 
  /* GDI has rendered the glyph, now we allocate a sprite and copy the image into it. */
  SpriteLoader::SpriteCollection spritecollection;
  SpriteLoader::Sprite &sprite = spritecollection[ZoomLevel::Min];
  sprite.AllocateData(ZoomLevel::Min, width * height);
  sprite.colours = SpriteComponent::Palette;
  if (aa) sprite.colours.Set(SpriteComponent::Alpha);
  sprite.width = width;
  sprite.height = height;
  sprite.x_offs = gm.gmptGlyphOrigin.x;
  sprite.y_offs = this->ascender - gm.gmptGlyphOrigin.y;
 
  if (size > 0) {
    /* All pixel data returned by GDI is in the form of DWORD-aligned rows.
     * For a non anti-aliased glyph, the returned bitmap has one bit per pixel.
     * For anti-aliased rendering, GDI uses the strange value range of 0 to 64,
     * inclusively. To map this to 0 to 255, we shift left by two and then
     * subtract one. */
    uint pitch = Align(aa ? gm.gmBlackBoxX : std::max((gm.gmBlackBoxX + 7u) / 8u, 1u), 4);
 
    /* Draw shadow for medium size. */
    if (this->fs == FontSize::Normal && !aa) {
      for (uint y = 0; y < gm.gmBlackBoxY; y++) {
        for (uint x = 0; x < gm.gmBlackBoxX; x++) {
          if (aa ? (bmp[x + y * pitch] > 0) : HasBit(bmp[(x / 8) + y * pitch], 7 - (x % 8))) {
            sprite.data[shadow + x + (shadow + y) * sprite.width].m = SHADOW_COLOUR;
            sprite.data[shadow + x + (shadow + y) * sprite.width].a = aa ? (bmp[x + y * pitch] << 2) - 1 : 0xFF;
          }
        }
      }
    }
 
    for (uint y = 0; y < gm.gmBlackBoxY; y++) {
      for (uint x = 0; x < gm.gmBlackBoxX; x++) {
        if (aa ? (bmp[x + y * pitch] > 0) : HasBit(bmp[(x / 8) + y * pitch], 7 - (x % 8))) {
          sprite.data[x + y * sprite.width].m = FACE_COLOUR;
          sprite.data[x + y * sprite.width].a = aa ? (bmp[x + y * pitch] << 2) - 1 : 0xFF;
        }
      }
    }
  }
 
  UniquePtrSpriteAllocator allocator;
  BlitterFactory::GetCurrentBlitter()->Encode(SpriteType::Font, spritecollection, allocator);
 
  GlyphEntry new_glyph;
  new_glyph.data = std::move(allocator.data);
  new_glyph.width = gm.gmCellIncX;
 
  return this->SetGlyphPtr(key, std::move(new_glyph)).GetSprite();
}
 
/* virtual */ GlyphID Win32FontCache::MapCharToGlyph(char32_t key, bool allow_fallback)
{
  assert(IsPrintable(key));
 
  /* Convert characters outside of the BMP into surrogate pairs. */
  WCHAR chars[2];
  if (key >= 0x010000U) {
    chars[0] = (wchar_t)(((key - 0x010000U) >> 10) + 0xD800);
    chars[1] = (wchar_t)(((key - 0x010000U) & 0x3FF) + 0xDC00);
  } else {
    chars[0] = (wchar_t)(key & 0xFFFF);
  }
 
  WORD glyphs[2] = { 0, 0 };
  GetGlyphIndicesW(this->dc, chars, key >= 0x010000U ? 2 : 1, glyphs, GGI_MARK_NONEXISTING_GLYPHS);
 
  if (glyphs[0] != 0xFFFF) return glyphs[0];
  return allow_fallback && key >= SCC_SPRITE_START && key <= SCC_SPRITE_END ? this->parent->MapCharToGlyph(key) : 0;
}
 
class Win32FontCacheFactory : FontCacheFactory {
public:
  Win32FontCacheFactory() : FontCacheFactory("win32", "Win32 font loader") {}
 
  std::unique_ptr<FontCache> LoadFont(FontSize fs, FontType fonttype, bool search, const std::string &font_name, const std::any &os_handle) const override
  {
    if (fonttype != FontType::TrueType) return nullptr;
 
    LOGFONT logfont{};
    logfont.lfPitchAndFamily = fs == FontSize::Monospace ? FIXED_PITCH : VARIABLE_PITCH;
    logfont.lfCharSet = DEFAULT_CHARSET;
    logfont.lfOutPrecision = OUT_OUTLINE_PRECIS;
    logfont.lfClipPrecision = CLIP_DEFAULT_PRECIS;
 
    /* If a GDI font description is present, e.g. from the automatic font
     * fallback search, use it. Otherwise, try to resolve it by font name. */
    if (auto ptr = std::any_cast<LOGFONT>(&os_handle)) {
      logfont = *ptr;
    } else if (font_name.find('.') != std::string::npos) {
      /* Might be a font file name, try load it. */
      if (!TryLoadFontFromFile(font_name, logfont)) {
        ShowInfo("Unable to load file '{}' for {} font, using default windows font selection instead", font_name, FontSizeToName(fs));
        if (!search) return nullptr;
      }
    }
 
    if (logfont.lfFaceName[0] == 0) {
      logfont.lfWeight = StrContainsIgnoreCase(font_name, " bold") ? FW_BOLD : FW_NORMAL; // Poor man's way to allow selecting bold fonts.
      convert_to_fs(font_name, logfont.lfFaceName);
    }
 
    return LoadWin32Font(fs, logfont, GetFontCacheFontSize(fs), font_name);
  }
 
  bool FindFallbackFont(const std::string &language_isocode, MissingGlyphSearcher *callback) const override
  {
    Debug(fontcache, 1, "Trying fallback fonts");
    EFCParam langInfo;
    std::wstring lang = OTTD2FS(language_isocode.substr(0, language_isocode.find('_')));
    if (GetLocaleInfoEx(lang.c_str(), LOCALE_FONTSIGNATURE, reinterpret_cast<LPWSTR>(&langInfo.locale), sizeof(langInfo.locale) / sizeof(wchar_t)) == 0) {
      /* Invalid isocode or some other mysterious error, can't determine fallback font. */
      Debug(fontcache, 1, "Can't get locale info for fallback font (isocode={})", language_isocode);
      return false;
    }
    langInfo.callback = callback;
 
    LOGFONT font;
    /* Enumerate all fonts. */
    font.lfCharSet = DEFAULT_CHARSET;
    font.lfFaceName[0] = '\0';
    font.lfPitchAndFamily = 0;
 
    HDC dc = GetDC(nullptr);
    int ret = EnumFontFamiliesEx(dc, &font, (FONTENUMPROC)&EnumFontCallback, (LPARAM)&langInfo, 0);
    ReleaseDC(nullptr, dc);
    return ret == 0;
  }
 
private:
  static std::unique_ptr<FontCache> LoadWin32Font(FontSize fs, const LOGFONT &logfont, uint size, std::string_view font_name)
  {
    HFONT font = CreateFontIndirect(&logfont);
    if (font == nullptr) {
      ShowInfo("Unable to use '{}' for {} font, Win32 reported error 0x{:X}, using sprite font instead", font_name, FontSizeToName(fs), GetLastError());
      return nullptr;
    }
    DeleteObject(font);
 
    return std::make_unique<Win32FontCache>(fs, logfont, size);
  }

  static bool TryLoadFontFromFile(const std::string &font_name, LOGFONT &logfont)
  {
    wchar_t fontPath[MAX_PATH] = {};
 
    /* See if this is an absolute path. */
    if (FileExists(font_name)) {
      convert_to_fs(font_name, fontPath);
    } else {
      /* Scan the search-paths to see if it can be found. */
      std::string full_font = FioFindFullPath(Subdirectory::Base, font_name);
      if (!full_font.empty()) {
        convert_to_fs(font_name, fontPath);
      }
    }
 
    if (fontPath[0] != 0) {
      if (AddFontResourceEx(fontPath, FR_PRIVATE, 0) != 0) {
        /* Try a nice little undocumented function first for getting the internal font name.
         * Some documentation is found at: http://www.undocprint.org/winspool/getfontresourceinfo */
        static LibraryLoader _gdi32("gdi32.dll");
        typedef BOOL(WINAPI *PFNGETFONTRESOURCEINFO)(LPCTSTR, LPDWORD, LPVOID, DWORD);
        static PFNGETFONTRESOURCEINFO GetFontResourceInfo = _gdi32.GetFunction("GetFontResourceInfoW");
 
        if (GetFontResourceInfo != nullptr) {
          /* Try to query an array of LOGFONTs that describe the file. */
          DWORD len = 0;
          if (GetFontResourceInfo(fontPath, &len, nullptr, 2) && len >= sizeof(LOGFONT)) {
            LOGFONT *buf = (LOGFONT *)new uint8_t[len];
            if (GetFontResourceInfo(fontPath, &len, buf, 2)) {
              logfont = *buf; // Just use first entry.
            }
            delete[](uint8_t *)buf;
          }
        }
 
        /* No dice yet. Use the file name as the font face name, hoping it matches. */
        if (logfont.lfFaceName[0] == 0) {
          wchar_t fname[_MAX_FNAME];
          _wsplitpath(fontPath, nullptr, nullptr, fname, nullptr);
 
          wcsncpy_s(logfont.lfFaceName, lengthof(logfont.lfFaceName), fname, _TRUNCATE);
          logfont.lfWeight = StrContainsIgnoreCase(font_name, " bold") || StrContainsIgnoreCase(font_name, "-bold") ? FW_BOLD : FW_NORMAL; // Poor man's way to allow selecting bold fonts.
        }
      }
    }
 
    return logfont.lfFaceName[0] != 0;
  }
 
private:
  static Win32FontCacheFactory instance;
};
 
/* static */ Win32FontCacheFactory Win32FontCacheFactory::instance;