6 files changed, 30 insertions, 10 deletions
diff --git a/indra/llrender/llfontbitmapcache.cpp b/indra/llrender/llfontbitmapcache.cpp
index ee9cfd0719..83f5d31186 100644
--- a/indra/llrender/llfontbitmapcache.cpp
+++ b/indra/llrender/llfontbitmapcache.cpp
@@ -107,7 +107,7 @@ bool LLFontBitmapCache::nextOpenPos(S32 width, S32& pos_x, S32& pos_y, EFontGlyp
             mBitmapHeight = image_height;
 
             S32 num_components = getNumComponents(bitmap_type);
-            mImageRawVec[bitmap_idx].push_back(new LLImageRaw(mBitmapWidth, mBitmapHeight, num_components));
+            mImageRawVec[bitmap_idx].emplace_back(new LLImageRaw(mBitmapWidth, mBitmapHeight, num_components));
             bitmap_num = static_cast<U32>(mImageRawVec[bitmap_idx].size()) - 1;
 
             LLImageRaw* image_raw = getImageRaw(bitmap_type, bitmap_num);
@@ -117,7 +117,7 @@ bool LLFontBitmapCache::nextOpenPos(S32 width, S32& pos_x, S32& pos_y, EFontGlyp
             }
 
             // Make corresponding GL image.
-            mImageGLVec[bitmap_idx].push_back(new LLImageGL(image_raw, false, false));
+            mImageGLVec[bitmap_idx].emplace_back(new LLImageGL(image_raw, false, false));
             LLImageGL* image_gl = getImageGL(bitmap_type, bitmap_num);
 
             // Start at beginning of the new image.
diff --git a/indra/llrender/llfontfreetype.h b/indra/llrender/llfontfreetype.h
index 1ad795060a..a2d925c5f6 100644
--- a/indra/llrender/llfontfreetype.h
+++ b/indra/llrender/llfontfreetype.h
@@ -148,6 +148,7 @@ public:
 
     void setStyle(U8 style);
     U8 getStyle() const;
+    S32 getAddedGlyphs() const { return mAddGlyphCount; }
 
 private:
     void resetBitmapCache();
diff --git a/indra/llrender/llfontgl.cpp b/indra/llrender/llfontgl.cpp
index 91242f4947..4037c036e5 100644
--- a/indra/llrender/llfontgl.cpp
+++ b/indra/llrender/llfontgl.cpp
@@ -110,6 +110,11 @@ S32 LLFontGL::getNumFaces(const std::string& filename)
     return mFontFreetype->getNumFaces(filename);
 }
 
+S32 LLFontGL::getKnownGlyphCount() const
+{
+    return mFontFreetype ? mFontFreetype->getAddedGlyphs() : 0;
+}
+
 S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, const LLRect& rect, const LLColor4 &color, HAlign halign, VAlign valign, U8 style,
     ShadowType shadow, S32 max_chars, F32* right_x, bool use_ellipses, bool use_color) const
 {
@@ -250,6 +255,10 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
 
     const LLFontBitmapCache* font_bitmap_cache = mFontFreetype->getFontBitmapCache();
 
+    // This looks wrong, value is dynamic.
+    // LLFontBitmapCache::nextOpenPos can alter these values when
+    // new characters get added to cache, which affects whole string.
+    // Todo: Perhaps value should update after symbols were added?
     F32 inv_width = 1.f / font_bitmap_cache->getBitmapWidth();
     F32 inv_height = 1.f / font_bitmap_cache->getBitmapHeight();
 
@@ -271,12 +280,14 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
 
     const LLFontGlyphInfo* next_glyph = NULL;
 
+    // string can have more than one glyph per char (ex: bold or shadow),
+    // make sure that GLYPH_BATCH_SIZE won't end up with half a symbol.
+    // See drawGlyph.
+    // Ex: with shadows it's 6 glyps per char. 30 fits exactly 5 chars.
     static constexpr S32 GLYPH_BATCH_SIZE = 30;
-    // string can have more than one glyph per char, make sure last one can fit
-    static constexpr S32 BUFFER_SIZE = GLYPH_BATCH_SIZE * 2;
-    static thread_local LLVector4a vertices[BUFFER_SIZE * 6];
-    static thread_local LLVector2 uvs[BUFFER_SIZE * 6];
-    static thread_local LLColor4U colors[BUFFER_SIZE * 6];
+    static thread_local LLVector4a vertices[GLYPH_BATCH_SIZE * 6];
+    static thread_local LLVector2 uvs[GLYPH_BATCH_SIZE * 6];
+    static thread_local LLColor4U colors[GLYPH_BATCH_SIZE * 6];
 
     LLColor4U text_color(color);
     // Preserve the transparency to render fading emojis in fading text (e.g.
@@ -321,8 +332,9 @@ S32 LLFontGL::render(const LLWString &wstr, S32 begin_offset, F32 x, F32 y, cons
             LLImageGL* font_image = font_bitmap_cache->getImageGL(bitmap_entry.first, bitmap_entry.second);
             gGL.getTexUnit(0)->bind(font_image);
 
-            // For multi-byte characters just draw each time character changes
-            // Might be overkill and might be better to detect multybyte
+            // For some reason it's not enough to compare by bitmap_entry.
+            // Issue hits emojis, japenese and chinese glyphs, only on first run.
+            // Todo: figure it out, there might be a bug with raw image data.
             last_char = wch;
         }
 
diff --git a/indra/llrender/llfontgl.h b/indra/llrender/llfontgl.h
index 9b63fc7c38..73efc6b1eb 100644
--- a/indra/llrender/llfontgl.h
+++ b/indra/llrender/llfontgl.h
@@ -90,6 +90,7 @@ public:
     bool loadFace(const std::string& filename, F32 point_size, const F32 vert_dpi, const F32 horz_dpi, bool is_fallback, S32 face_n);
 
     S32 getNumFaces(const std::string& filename);
+    S32 getKnownGlyphCount() const;
 
     S32 render(const LLWString &text, S32 begin_offset,
                 const LLRect& rect,
diff --git a/indra/llrender/llfontvertexbuffer.cpp b/indra/llrender/llfontvertexbuffer.cpp
index 17b23c420d..b53a841a87 100644
--- a/indra/llrender/llfontvertexbuffer.cpp
+++ b/indra/llrender/llfontvertexbuffer.cpp
@@ -147,7 +147,8 @@ S32 LLFontVertexBuffer::render(
              || mLastVertDPI != LLFontGL::sVertDPI
              || mLastHorizDPI != LLFontGL::sHorizDPI
              || mLastOrigin != LLFontGL::sCurOrigin
-             || mLastResGeneration != LLFontGL::sResolutionGeneration)
+             || mLastResGeneration != LLFontGL::sResolutionGeneration
+             || mLastFontGlyphCount != fontp->getKnownGlyphCount())
     {
         genBuffers(fontp, text, begin_offset, x, y, color, halign, valign,
             style, shadow, max_chars, max_pixels, right_x, use_ellipses, use_color);
@@ -203,6 +204,7 @@ void LLFontVertexBuffer::genBuffers(
     mLastHorizDPI = LLFontGL::sHorizDPI;
     mLastOrigin = LLFontGL::sCurOrigin;
     mLastResGeneration = LLFontGL::sResolutionGeneration;
+    mLastFontGlyphCount = fontp->getKnownGlyphCount();
 
     if (right_x)
     {
diff --git a/indra/llrender/llfontvertexbuffer.h b/indra/llrender/llfontvertexbuffer.h
index f244e7fefa..d5e1280dbf 100644
--- a/indra/llrender/llfontvertexbuffer.h
+++ b/indra/llrender/llfontvertexbuffer.h
@@ -120,6 +120,10 @@ private:
     S32 mLastResGeneration = 0;
     LLCoordGL mLastOrigin;
 
+    // Adding new characters to bitmap cache can alter value from getBitmapWidth();
+    // which alters whole string. So rerender when new characters were added to cache.
+    S32 mLastFontGlyphCount = 0;
+
     static bool sEnableBufferCollection;
 };