Commit b852883a authored by mozilla@weilbacher.org's avatar mozilla@weilbacher.org
Browse files

[OS/2] Get gfxOS2Font::GetMetrics() in order 

- metrics.y_ppem should not get scaled
- if the space width is too small it's the fault of the font, don't scale it
- add mimimum comment for the function
- add some more debugging output, we'll probably need it again sometime
parent 3f2b0ce1

gfx/thebes/src/gfxOS2Fonts.cpp

+20 −4
Original line number Diff line number Diff line
@@ -94,6 +94,11 @@ gfxOS2Font::~gfxOS2Font() 
#define CONVERT_DESIGN_UNITS_TO_PIXELS_Y(v) \

        CONVERT_DESIGN_UNITS_TO_PIXELS(v, face->size->metrics.y_scale)



// gfxOS2Font::GetMetrics()

// return the metrics of the current font using the gfxFont metrics structure.

// If the metrics are not available yet, compute them using the FreeType

// function on the font. (This is partly based on the respective function from

// gfxPangoFonts)

const gfxFont::Metrics& gfxOS2Font::GetMetrics()

{

#ifdef DEBUG_thebes_1
@@ -115,7 +120,7 @@ const gfxFont::Metrics& gfxOS2Font::GetMetrics() 
        FT_Load_Glyph(face, gid, FT_LOAD_DEFAULT);

        // face->glyph->metrics.width doesn't work for spaces, use advance.x instead

        // spaces are always too narrow, unless I multiply by some extra factor

        mMetrics->spaceWidth = CONVERT_DESIGN_UNITS_TO_PIXELS_X(face->glyph->advance.x) * 2;

        mMetrics->spaceWidth = CONVERT_DESIGN_UNITS_TO_PIXELS_X(face->glyph->advance.x);

        // save the space glyph

        mSpaceGlyph = gid;
@@ -134,11 +139,12 @@ const gfxFont::Metrics& gfxOS2Font::GetMetrics() 
        // could access these via os2 table, but copy behavior from gfxPangoFonts

        mMetrics->strikeoutOffset = mMetrics->xHeight / 2.0;

        mMetrics->strikeoutSize   = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->underline_thickness);

        // seems that underlineOffset really has to be negative

        mMetrics->underlineOffset = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->underline_position);

        mMetrics->underlineSize   = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->underline_thickness);

    

        // descents are negative in FT but Thebes wants them positive

        mMetrics->emHeight        = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->size->metrics.y_ppem);

        mMetrics->emHeight        = face->size->metrics.y_ppem;

        mMetrics->emAscent        = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->ascender);

        mMetrics->emDescent       = -CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->descender);

        mMetrics->maxHeight       = CONVERT_DESIGN_UNITS_TO_PIXELS_Y(face->height);
@@ -156,17 +162,27 @@ const gfxFont::Metrics& gfxOS2Font::GetMetrics() 
    

#ifdef DEBUG_thebes_1

        printf("gfxOS2Font[%#x]::GetMetrics():\n"

               "  %s\n"

               "  emHeight=%f==%f=gfxFont::mStyle.size\n"

               "  maxHeight=%f\n"

               "  xHeight=%f\n"

               "  aveCharWidth=%f==xWidth\n"

               "  spaceWidth=%f\n",

               "  spaceWidth=%f\n"

               "  others: %f %f   %f %f   %f %f\n      %f %f %f   %f %f %f\n      %f %f\n",

               (unsigned)this,

               NS_LossyConvertUTF16toASCII(mName).get(),

               mMetrics->emHeight, mStyle.size,

               mMetrics->maxHeight,

               mMetrics->xHeight,

               mMetrics->aveCharWidth,

               mMetrics->spaceWidth);

               mMetrics->spaceWidth,

               mMetrics->superscriptOffset, mMetrics->subscriptOffset,

               mMetrics->strikeoutOffset, mMetrics->strikeoutSize,

               mMetrics->underlineOffset, mMetrics->underlineSize,

               mMetrics->emAscent, mMetrics->emDescent, mMetrics->maxHeight,

               mMetrics->maxAscent, mMetrics->maxDescent, mMetrics->maxAdvance,

               mMetrics->internalLeading, mMetrics->externalLeading

              );

#endif

        cairo_ft_scaled_font_unlock_face(CairoScaledFont());

    }