diff options
Diffstat (limited to 'gtk/PlatGTK.cxx')
| -rwxr-xr-x | gtk/PlatGTK.cxx | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/gtk/PlatGTK.cxx b/gtk/PlatGTK.cxx index 283dd7a4b..e7d6abd3d 100755 --- a/gtk/PlatGTK.cxx +++ b/gtk/PlatGTK.cxx @@ -36,6 +36,7 @@ #include "Scintilla.h" #include "ScintillaWidget.h" +#include "CharacterType.h" #include "XPM.h" #include "UniConversion.h" @@ -1085,6 +1086,27 @@ void SurfaceImpl::MeasureWidthsUTF8(const Font *font_, std::string_view text, XY } while (!iti.finished) { iti.Next(); + if (iti.curIndex < i) { + // Backwards movement indicater bidirectional. + // Divide into ASCII prefix and non-ASCII suffix as this is common case + // and produces accurate positions for the ASCII prefix. + size_t lenASCII=0; + while (lenASCII<text.length() && IsASCII(text[lenASCII])) { + lenASCII++; + } + const std::string_view asciiPrefix = text.substr(0, lenASCII); + const std::string_view bidiSuffix = text.substr(lenASCII); + // Recurse for ASCII prefix. + MeasureWidthsUTF8(font_, asciiPrefix, positions); + // Measure the whole bidiSuffix and spread its width evenly + const XYPOSITION endASCII = positions[lenASCII-1]; + const XYPOSITION widthBidi = WidthText(font_, bidiSuffix); + const XYPOSITION widthByteBidi = widthBidi / bidiSuffix.length(); + for (size_t bidiPos=0; bidiPos<bidiSuffix.length(); bidiPos++) { + positions[bidiPos+lenASCII] = endASCII + widthByteBidi * (bidiPos + 1); + } + return; + } const int places = iti.curIndex - i; while (i < iti.curIndex) { // Evenly distribute space among bytes of this cluster. |