#5966 Fixed width font's numbers

Dejavu used fixed width numbers by default, tweaked fonts to do the same
for inter (when weight > 0).

3 files changed, 62 insertions, 6 deletions

diff --git a/indra/llrender/llfontfreetype.cpp b/indra/llrender/llfontfreetype.cpp
index 3c5682dfc9..bc4020a06b 100644
--- a/indra/llrender/llfontfreetype.cpp
+++ b/indra/llrender/llfontfreetype.cpp
@@ -109,6 +109,7 @@ LLFontManager::~LLFontManager()
 LLFontGlyphInfo::LLFontGlyphInfo(U32 index, EFontGlyphType glyph_type)
 :   mGlyphIndex(index),
     mGlyphType(glyph_type),
+    mChar(0),
     mWidth(0),          // In pixels
     mHeight(0),         // In pixels
     mXAdvance(0.f),     // In pixels
@@ -126,6 +127,7 @@ LLFontGlyphInfo::LLFontGlyphInfo(U32 index, EFontGlyphType glyph_type)
 LLFontGlyphInfo::LLFontGlyphInfo(const LLFontGlyphInfo& fgi)
     : mGlyphIndex(fgi.mGlyphIndex)
     , mGlyphType(fgi.mGlyphType)
+    , mChar(fgi.mChar)
     , mWidth(fgi.mWidth)
     , mHeight(fgi.mHeight)
     , mXAdvance(fgi.mXAdvance)
@@ -150,7 +152,8 @@ LLFontFreetype::LLFontFreetype()
     mFTFace(nullptr),
     mRenderGlyphCount(0),
     mStyle(0),
-    mPointSize(0)
+    mPointSize(0),
+    mMaxDigitWidth(0.0f)
 {
 }
 
@@ -343,6 +346,10 @@ F32 LLFontFreetype::getXAdvance(llwchar wch) const
     LLFontGlyphInfo* gi = getGlyphInfo(wch, EFontGlyphType::Unspecified);
     if (gi)
     {
+        if (wch >= '0' && wch <= '9' && mMaxDigitWidth > 0.0f)
+        {
+            return mMaxDigitWidth;
+        }
         return gi->mXAdvance;
     }
     else
@@ -363,6 +370,12 @@ F32 LLFontFreetype::getXAdvance(const LLFontGlyphInfo* glyph) const
     if (mFTFace == nullptr)
         return 0.0;
 
+    // Use max digit width for tabular numbers
+    if (mWeight > 0 && glyph->mChar >= '0' && glyph->mChar <= '9' && mMaxDigitWidth > 0.0f)
+    {
+        return mMaxDigitWidth;
+    }
+
     return glyph->mXAdvance;
 }
 
@@ -384,8 +397,27 @@ F32 LLFontFreetype::getXKerning(const LLFontGlyphInfo* left_glyph_info, const LL
     if (mFTFace == nullptr)
         return 0.0;
 
-    U32 left_glyph = left_glyph_info ? left_glyph_info->mGlyphIndex : 0;
-    U32 right_glyph = right_glyph_info ? right_glyph_info->mGlyphIndex : 0;
+    U32 left_glyph = 0;
+    U32 right_glyph = 0;
+
+    if (left_glyph_info)
+    {
+        if (mWeight > 0 && left_glyph_info->mChar >= '0' && left_glyph_info->mChar <= '9')
+        {
+            // Disable kerning for digits when using tabular numbers
+            return 0.0;
+        }
+        left_glyph = left_glyph_info->mGlyphIndex;
+    }
+    if (right_glyph_info)
+    {
+        if (mWeight > 0 && right_glyph_info->mChar >= '0' && right_glyph_info->mChar <= '9')
+        {
+            // Disable kerning for digits when using tabular numbers
+            return 0.0;
+        }
+        right_glyph = right_glyph_info->mGlyphIndex;
+    }
 
     FT_Vector  delta;
 
@@ -548,6 +580,7 @@ LLFontGlyphInfo* LLFontFreetype::addGlyphFromFont(const LLFontFreetype *fontp, l
     mFontBitmapCachep->nextOpenPos(width, pos_x, pos_y, bitmap_glyph_type, bitmap_num);
 
     LLFontGlyphInfo* gi = new LLFontGlyphInfo(glyph_index, requested_glyph_type);
+    gi->mChar = wch;
     gi->mXBitmapOffset = pos_x;
     gi->mYBitmapOffset = pos_y;
     gi->mBitmapEntry = std::make_pair(bitmap_glyph_type, bitmap_num);
@@ -564,6 +597,14 @@ LLFontGlyphInfo* LLFontFreetype::addGlyphFromFont(const LLFontFreetype *fontp, l
     gi->mXAdvance = fontp->mFTFace->glyph->advance.x / 64.f;
     gi->mYAdvance = fontp->mFTFace->glyph->advance.y / 64.f;
 
+    if (mWeight > 0 && wch >= '0' && wch <= '9')
+    {
+        // Digits are supposed to be preloaded, and buffers
+        // refresh when new chars get added, so this lazy load
+        // should not cause any issues.
+        mMaxDigitWidth = llmax(mMaxDigitWidth, gi->mXAdvance);
+    }
+
     insertGlyphInfo(wch, gi);
 
     if (requested_glyph_type != bitmap_glyph_type)
@@ -799,6 +840,7 @@ void LLFontFreetype::resetBitmapCache()
     }
     mCharGlyphInfoMap.clear();
     mFontBitmapCachep->reset();
+    mMaxDigitWidth = 0.0f;
 
     // Adding default glyph is skipped for fallback fonts here as well as in loadFace().
     // This if was added as fix for EXT-4971.
diff --git a/indra/llrender/llfontfreetype.h b/indra/llrender/llfontfreetype.h
index d2164e8fa2..461e064766 100644
--- a/indra/llrender/llfontfreetype.h
+++ b/indra/llrender/llfontfreetype.h
@@ -76,6 +76,8 @@ struct LLFontGlyphInfo
 
     U32 mGlyphIndex;
     EFontGlyphType mGlyphType;
+    llwchar mChar;
+
 
     // Metrics
     S32 mWidth;         // In pixels
@@ -147,6 +149,9 @@ public:
     F32 getXKerning(llwchar char_left, llwchar char_right) const; // Get the kerning between the two characters
     F32 getXKerning(const LLFontGlyphInfo* left_glyph_info, const LLFontGlyphInfo* right_glyph_info) const; // Get the kerning between the two characters
 
+    F32 getMaxDigitWidth() const { return mMaxDigitWidth; }
+    S32 getFontWeight() const { return mWeight; }
+
     LLFontGlyphInfo* getGlyphInfo(llwchar wch, EFontGlyphType glyph_type) const;
 
     void reset(F32 vert_dpi, F32 horz_dpi);
@@ -184,6 +189,7 @@ private:
     F32 mAscender;
     F32 mDescender;
     F32 mLineHeight;
+    mutable F32 mMaxDigitWidth;
 
     LLFT_Face mFTFace;
 
diff --git a/indra/llrender/llfontgl.cpp b/indra/llrender/llfontgl.cpp
index 5d99c35047..bb5a12375e 100644
--- a/indra/llrender/llfontgl.cpp
+++ b/indra/llrender/llfontgl.cpp
@@ -345,6 +345,14 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
             break;
         }
 
+        // Calculate horizontal offset for tabular numbers (center narrow digits)
+        F32 x_offset = 0.0f;
+        if (mFontFreetype->getFontWeight() > 0 && fgi->mChar >= '0' && fgi->mChar <= '9' && mFontFreetype->getMaxDigitWidth() > 0.0f)
+        {
+            // use mXAdvance directly here, since we don't want to get max width instead.
+            x_offset = (mFontFreetype->getMaxDigitWidth() - fgi->mXAdvance) * 0.5f;
+        }
+
         // Draw the text at the appropriate location
         //Specify vertices and texture coordinates
         LLRectf uv_rect((fgi->mXBitmapOffset) * inv_width,
@@ -352,9 +360,9 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
                 (fgi->mXBitmapOffset + fgi->mWidth) * inv_width,
                 (fgi->mYBitmapOffset - PAD_UVY) * inv_height);
         // snap glyph origin to whole screen pixel
-        LLRectf screen_rect((F32)ll_round(cur_render_x + (F32)fgi->mXBearing),
+        LLRectf screen_rect((F32)ll_round(cur_render_x + (F32)fgi->mXBearing + x_offset),
                     (F32)ll_round(cur_render_y + (F32)fgi->mYBearing),
-                    (F32)ll_round(cur_render_x + (F32)fgi->mXBearing) + (F32)fgi->mWidth,
+                    (F32)ll_round(cur_render_x + (F32)fgi->mXBearing + x_offset) + (F32)fgi->mWidth,
                     (F32)ll_round(cur_render_y + (F32)fgi->mYBearing) - (F32)fgi->mHeight);
 
         if (glyph_count >= GLYPH_BATCH_SIZE)
@@ -375,7 +383,7 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
                   col, style_to_add, shadow, drop_shadow_strength);
 
         chars_drawn++;
-        cur_x += fgi->mXAdvance;
+        cur_x += mFontFreetype->getXAdvance(fgi);
         cur_y += fgi->mYAdvance;
 
         llwchar next_char = wstr[i+1];