Skip to content

Commit

Permalink
SDL: Add more fallback font names, greatly speed up fallback font han…
Browse files Browse the repository at this point in the history 
…dling
  • Loading branch information
@hrydgard
hrydgard committed Jan 20, 2024
1 parent 5de1a5f commit 1553931
Show file tree
Hide file tree
Showing 2 changed files with 88 additions and 25 deletions.
107 changes: 84 additions & 23 deletions Common/Render/Text/draw_text_sdl.cpp
View file
Expand Up @@ -18,6 +18,18 @@
#include "SDL2/SDL.h"
#include "SDL2/SDL_ttf.h"

static std::string getlocale() {
// setlocale is not an intuitive function...
char *curlocale = setlocale(LC_CTYPE, nullptr);
std::string loc = curlocale ? std::string(curlocale) : "en_US";
size_t ptPos = loc.find('.');
// Remove any secondary specifier.
if (ptPos != std::string::npos) {
loc.resize(ptPos);
}
return loc;
}

TextDrawerSDL::TextDrawerSDL(Draw::DrawContext *draw): TextDrawer(draw) {
if (TTF_Init() < 0) {
ERROR_LOG(G3D, "Unable to initialize SDL2_ttf");
Expand All @@ -29,7 +41,7 @@ TextDrawerSDL::TextDrawerSDL(Draw::DrawContext *draw): TextDrawer(draw) {
config = FcInitLoadConfigAndFonts();
#endif

PrepareFallbackFonts();
PrepareFallbackFonts(getlocale());
}

TextDrawerSDL::~TextDrawerSDL() {
Expand All @@ -44,25 +56,56 @@ TextDrawerSDL::~TextDrawerSDL() {
}

// If a user complains about missing characters on SDL, re-visit this!
void TextDrawerSDL::PrepareFallbackFonts() {
void TextDrawerSDL::PrepareFallbackFonts(std::string_view locale) {
#if defined(USE_SDL2_TTF_FONTCONFIG)
FcObjectSet *os = FcObjectSetBuild (FC_FILE, FC_INDEX, (char *) 0);

// To install the fallback font in ubuntu:
// To install the recommended Droid Sans fallback font in Ubuntu:
// sudo apt install fonts-droid-fallback
const char *names[] = {
"Droid Sans Fallback",
const char *hardcodedNames[] = {
"Droid Sans Medium",
"Droid Sans Bold",
"Droid Sans Fallback",
"Source Han Sans Medium",
"DejaVu Sans Condensed",
"Noto Sans CJK Medium",
"Noto Sans Hebrew Medium",
"Noto Sans Lao Medium",
"Noto Sans Thai Medium",
"DejaVu Sans Condensed",
"DejaVu Sans",
"Meera Regular",
"FreeSans",
"Gargi",
"KacstDigital",
"KacstFarsi",
"Khmer OS",
"Paduak",
"Paduak",
"Jamrul",
};

for (int i = 0; i < ARRAY_SIZE(names); i++) {
std::vector<const char *> names;
if (locale == "zh_CN") {
names.push_back("Noto Sans CJK SC");
} else if (locale == "zh_TW") {
names.push_back("Noto Sans CJK TC");
names.push_back("Noto Sans CJK HK");
} else if (locale == "ja_JP") {
names.push_back("Noto Sans CJK JP");
} else if (locale == "ko_KR") {
names.push_back("Noto Sans CJK KR");
} else {
// Let's just pick one.
names.push_back("Noto Sans CJK JP");
}

// Then push all the hardcoded ones.
for (int i = 0; i < ARRAY_SIZE(hardcodedNames); i++) {
names.push_back(hardcodedNames[i]);
}

// First, add the region-specific Noto fonts according to the locale.

for (int i = 0; i < names.size(); i++) {
// printf("trying font name %s\n", names[i]);
FcPattern *name = FcNameParse((const FcChar8 *)names[i]);
FcFontSet *foundFonts = FcFontList(config, name, os);
Expand Down Expand Up @@ -159,34 +202,42 @@ uint32_t TextDrawerSDL::CheckMissingGlyph(const std::string& text) {
return missingGlyph;
}

// If this returns true, the first font in fallbackFonts_ can be used as a fallback.
bool TextDrawerSDL::FindFallbackFonts(uint32_t missingGlyph, int ptSize) {
// If we encounter a missing glyph, try to use one of the fallback fonts.
// If this returns >= 0, the nth font in fallbackFonts_ can be used as a fallback.
int TextDrawerSDL::FindFallbackFonts(uint32_t missingGlyph, int ptSize) {
auto iter = glyphFallbackFontIndex_.find(missingGlyph);

if (iter != glyphFallbackFontIndex_.end()) {
return iter->second;
}

// If we encounter a missing glyph, try to use one of already loaded fallback fonts.
for (int i = 0; i < fallbackFonts_.size(); i++) {
TTF_Font *fallbackFont = fallbackFonts_[i];
if (TTF_GlyphIsProvided32(fallbackFont, missingGlyph)) {
fallbackFonts_.erase(fallbackFonts_.begin() + i);
fallbackFonts_.insert(fallbackFonts_.begin(), fallbackFont);
return true;
glyphFallbackFontIndex_[missingGlyph] = i;
return i;
}
}

// If none of the loaded fonts can handle it, load more fonts.
// TODO: Don't retry already tried fonts.
for (int i = 0; i < fallbackFontPaths_.size(); i++) {
std::string& fontPath = fallbackFontPaths_[i].first;
int faceIndex = fallbackFontPaths_[i].second;

TTF_Font *font = TTF_OpenFontIndex(fontPath.c_str(), ptSize, faceIndex);

if (TTF_GlyphIsProvided32(font, missingGlyph)) {
fallbackFonts_.insert(fallbackFonts_.begin(), font);
return true;
fallbackFonts_.push_back(font);
return fallbackFonts_.size() - 1;
} else {
TTF_CloseFont(font);
}
}

return false;
// Not found at all? Let's remember that for this glyph.
glyphFallbackFontIndex_[missingGlyph] = -1;
return -1;
}

uint32_t TextDrawerSDL::SetFont(const char *fontName, int size, int flags) {
Expand Down Expand Up @@ -234,13 +285,17 @@ void TextDrawerSDL::MeasureString(const char *str, size_t len, float *w, float *
if (iter != sizeCache_.end()) {
entry = iter->second.get();
} else {
printf("re-measuring %s\n", str);
TTF_Font *font = fontMap_.find(fontHash_)->second;
int ptSize = TTF_FontHeight(font) / 1.35;

uint32_t missingGlyph = CheckMissingGlyph(key.text);

if (missingGlyph && FindFallbackFonts(missingGlyph, ptSize)) {
font = fallbackFonts_[0];
if (missingGlyph) {
int fallbackFont = FindFallbackFonts(missingGlyph, ptSize);
if (fallbackFont >= 0) {
font = fallbackFonts_[fallbackFont];
}
}

int width = 0;
Expand Down Expand Up @@ -270,8 +325,11 @@ void TextDrawerSDL::MeasureStringRect(const char *str, size_t len, const Bounds
int ptSize = TTF_FontHeight(font) / 1.35;
uint32_t missingGlyph = CheckMissingGlyph(toMeasure);

if (missingGlyph && FindFallbackFonts(missingGlyph, ptSize)) {
font = fallbackFonts_[0];
if (missingGlyph) {
int fallbackFont = FindFallbackFonts(missingGlyph, ptSize);
if (fallbackFont >= 0) {
font = fallbackFonts_[fallbackFont];
}
}

std::vector<std::string> lines;
Expand Down Expand Up @@ -381,8 +439,11 @@ void TextDrawerSDL::DrawStringBitmap(std::vector<uint8_t> &bitmapData, TextStrin

uint32_t missingGlyph = CheckMissingGlyph(processedStr);

if (missingGlyph && FindFallbackFonts(missingGlyph, ptSize)) {
font = fallbackFonts_[0];
if (missingGlyph) {
int fallbackFont = FindFallbackFonts(missingGlyph, ptSize);
if (fallbackFont >= 0) {
font = fallbackFonts_[fallbackFont];
}
}

#if SDL_TTF_VERSION_ATLEAST(2, 20, 0)
Expand Down
6 changes: 4 additions & 2 deletions Common/Render/Text/draw_text_sdl.h
View file
Expand Up @@ -28,9 +28,9 @@ class TextDrawerSDL : public TextDrawer {

protected:
void ClearCache() override;
void PrepareFallbackFonts();
void PrepareFallbackFonts(std::string_view locale);
uint32_t CheckMissingGlyph(const std::string& text);
bool FindFallbackFonts(uint32_t missingGlyph, int ptSize);
int FindFallbackFonts(uint32_t missingGlyph, int ptSize);

uint32_t fontHash_;
std::map<uint32_t, _TTF_Font *> fontMap_;
Expand All @@ -41,6 +41,8 @@ class TextDrawerSDL : public TextDrawer {
std::vector<_TTF_Font *> fallbackFonts_;
std::vector<std::pair<std::string, int>> fallbackFontPaths_; // path and font face index

std::map<int, int> glyphFallbackFontIndex_;

#if defined(USE_SDL2_TTF_FONTCONFIG)
FcConfig *config;
#endif
Expand Down

0 comments on commit 1553931

Please sign in to comment.