diff --git a/imgui_draw.cpp b/imgui_draw.cpp
index 1cd2304..d256c8d 100644
--- a/imgui_draw.cpp
+++ b/imgui_draw.cpp
@@ -1921,7 +1921,7 @@
     int                 DstIndex;           // Index into atlas->Fonts[] and dst_tmp_array[]
     int                 GlyphsHighest;      // Highest requested codepoint
     int                 GlyphsCount;        // Glyph count (excluding missing glyphs and glyphs already set by an earlier source font)
-    ImBoolVector        GlyphsSet;          // Glyph bit map (random access, 1-bit per codepoint. This will be a maximum of 8KB)
+    ImBitVector         GlyphsSet;          // Glyph bit map (random access, 1-bit per codepoint. This will be a maximum of 8KB)
     ImVector<int>       GlyphsList;         // Glyph codepoints list (flattened version of GlyphsMap)
 };
 
@@ -1931,19 +1931,19 @@
     int                 SrcCount;           // Number of source fonts targeting this destination font.
     int                 GlyphsHighest;
     int                 GlyphsCount;
-    ImBoolVector        GlyphsSet;          // This is used to resolve collision when multiple sources are merged into a same destination font.
+    ImBitVector         GlyphsSet;          // This is used to resolve collision when multiple sources are merged into a same destination font.
 };
 
-static void UnpackBoolVectorToFlatIndexList(const ImBoolVector* in, ImVector<int>* out)
+static void UnpackBitVectorToFlatIndexList(const ImBitVector* in, ImVector<int>* out)
 {
     IM_ASSERT(sizeof(in->Storage.Data[0]) == sizeof(int));
-    const int* it_begin = in->Storage.begin();
-    const int* it_end = in->Storage.end();
-    for (const int* it = it_begin; it < it_end; it++)
-        if (int entries_32 = *it)
-            for (int bit_n = 0; bit_n < 32; bit_n++)
-                if (entries_32 & (1u << bit_n))
-                    out->push_back((int)((it - it_begin) << 5) + bit_n);
+    const ImU32* it_begin = in->Storage.begin();
+    const ImU32* it_end = in->Storage.end();
+    for (const ImU32* it = it_begin; it < it_end; it++)
+        if (ImU32 entries_32 = *it)
+            for (ImU32 bit_n = 0; bit_n < 32; bit_n++)
+                if (entries_32 & ((ImU32)1 << bit_n))
+                    out->push_back((int)(((it - it_begin) << 5) + bit_n));
 }
 
 bool    ImFontAtlasBuildWithStbTruetype(ImFontAtlas* atlas)
@@ -2004,14 +2004,14 @@
     {
         ImFontBuildSrcData& src_tmp = src_tmp_array[src_i];
         ImFontBuildDstData& dst_tmp = dst_tmp_array[src_tmp.DstIndex];
-        src_tmp.GlyphsSet.Resize(src_tmp.GlyphsHighest + 1);
+        src_tmp.GlyphsSet.Create(src_tmp.GlyphsHighest + 1);
         if (dst_tmp.GlyphsSet.Storage.empty())
-            dst_tmp.GlyphsSet.Resize(dst_tmp.GlyphsHighest + 1);
+            dst_tmp.GlyphsSet.Create(dst_tmp.GlyphsHighest + 1);
 
         for (const ImWchar* src_range = src_tmp.SrcRanges; src_range[0] && src_range[1]; src_range += 2)
             for (unsigned int codepoint = src_range[0]; codepoint <= src_range[1]; codepoint++)
             {
-                if (dst_tmp.GlyphsSet.GetBit(codepoint))    // Don't overwrite existing glyphs. We could make this an option for MergeMode (e.g. MergeOverwrite==true)
+                if (dst_tmp.GlyphsSet.TestBit(codepoint))    // Don't overwrite existing glyphs. We could make this an option for MergeMode (e.g. MergeOverwrite==true)
                     continue;
                 if (!stbtt_FindGlyphIndex(&src_tmp.FontInfo, codepoint))    // It is actually in the font?
                     continue;
@@ -2019,8 +2019,8 @@
                 // Add to avail set/counters
                 src_tmp.GlyphsCount++;
                 dst_tmp.GlyphsCount++;
-                src_tmp.GlyphsSet.SetBit(codepoint, true);
-                dst_tmp.GlyphsSet.SetBit(codepoint, true);
+                src_tmp.GlyphsSet.SetBit(codepoint);
+                dst_tmp.GlyphsSet.SetBit(codepoint);
                 total_glyphs_count++;
             }
     }
@@ -2030,7 +2030,7 @@
     {
         ImFontBuildSrcData& src_tmp = src_tmp_array[src_i];
         src_tmp.GlyphsList.reserve(src_tmp.GlyphsCount);
-        UnpackBoolVectorToFlatIndexList(&src_tmp.GlyphsSet, &src_tmp.GlyphsList);
+        UnpackBitVectorToFlatIndexList(&src_tmp.GlyphsSet, &src_tmp.GlyphsList);
         src_tmp.GlyphsSet.Clear();
         IM_ASSERT(src_tmp.GlyphsList.Size == src_tmp.GlyphsCount);
     }
diff --git a/imgui_internal.h b/imgui_internal.h
index d31f00e..eed5d82 100644
--- a/imgui_internal.h
+++ b/imgui_internal.h
@@ -73,7 +73,7 @@
 // Forward declarations
 //-----------------------------------------------------------------------------
 
-struct ImBoolVector;                // Store 1-bit per value
+struct ImBitVector;                 // Store 1-bit per value
 struct ImRect;                      // An axis-aligned rectangle (2 points)
 struct ImDrawDataBuilder;           // Helper to build a ImDrawData instance
 struct ImDrawListSharedData;        // Data shared between all ImDrawList instances
@@ -204,7 +204,8 @@
 // - Helpers: ImVec2/ImVec4 operators
 // - Helpers: Maths
 // - Helpers: Geometry
-// - Helper: ImBoolVector
+// - Helpers: Bit arrays
+// - Helper: ImBitVector
 // - Helper: ImPool<>
 // - Helper: ImChunkStream<>
 //-----------------------------------------------------------------------------
@@ -350,16 +351,32 @@
 inline float         ImTriangleArea(const ImVec2& a, const ImVec2& b, const ImVec2& c) { return ImFabs((a.x * (b.y - c.y)) + (b.x * (c.y - a.y)) + (c.x * (a.y - b.y))) * 0.5f; }
 IMGUI_API ImGuiDir   ImGetDirQuadrantFromDelta(float dx, float dy);
 
-// Helper: ImBoolVector
-// Store 1-bit per value. Note that Resize() currently clears the whole vector.
-struct IMGUI_API ImBoolVector
+// Helpers: Bit arrays
+inline bool          ImBitArrayTestBit(const ImU32* arr, int n)         { ImU32 mask = (ImU32)1 << (n & 31); return (arr[n >> 5] & mask) != 0; }
+inline void          ImBitArrayClearBit(ImU32* arr, int n)              { ImU32 mask = (ImU32)1 << (n & 31); arr[n >> 5] &= ~mask; }
+inline void          ImBitArraySetBit(ImU32* arr, int n)                { ImU32 mask = (ImU32)1 << (n & 31); arr[n >> 5] |= mask; }
+inline void          ImBitArraySetBitRange(ImU32* arr, int n, int n2)
 {
-    ImVector<int>   Storage;
-    ImBoolVector()  { }
-    void            Resize(int sz)          { Storage.resize((sz + 31) >> 5); memset(Storage.Data, 0, (size_t)Storage.Size * sizeof(Storage.Data[0])); }
-    void            Clear()                 { Storage.clear(); }
-    bool            GetBit(int n) const     { int off = (n >> 5); int mask = 1 << (n & 31); return (Storage[off] & mask) != 0; }
-    void            SetBit(int n, bool v)   { int off = (n >> 5); int mask = 1 << (n & 31); if (v) Storage[off] |= mask; else Storage[off] &= ~mask; }
+    while (n <= n2)
+    {
+        int a_mod = (n & 31);
+        int b_mod = ((n2 >= n + 31) ? 31 : (n2 & 31)) + 1;
+        ImU32 mask = (ImU32)(((ImU64)1 << b_mod) - 1) & ~(ImU32)(((ImU64)1 << a_mod) - 1);
+        arr[n >> 5] |= mask;
+        n = (n + 32) & ~31;
+    }
+}
+
+// Helper: ImBitVector
+// Store 1-bit per value.
+struct IMGUI_API ImBitVector
+{
+    ImVector<ImU32> Storage;
+    void            Create(int sz)              { Storage.resize((sz + 31) >> 5); memset(Storage.Data, 0, (size_t)Storage.Size * sizeof(Storage.Data[0])); }
+    void            Clear()                     { Storage.clear(); }
+    bool            TestBit(int n) const        { IM_ASSERT(n < (Storage.Size << 5)); return ImBitArrayTestBit(Storage.Data, n); }
+    void            SetBit(int n)               { IM_ASSERT(n < (Storage.Size << 5)); ImBitArraySetBit(Storage.Data, n); }
+    void            ClearBit(int n)             { IM_ASSERT(n < (Storage.Size << 5)); ImBitArrayClearBit(Storage.Data, n); }
 };
 
 // Helper: ImPool<>
diff --git a/misc/freetype/README.md b/misc/freetype/README.md
index 87b2736..e565097 100644
--- a/misc/freetype/README.md
+++ b/misc/freetype/README.md
@@ -5,7 +5,7 @@
 
 ### Usage
 
-1. Get latest FreeType binaries or build yourself (under Windows you may use vcpkg with `vcpkg install freetype`).
+1. Get latest FreeType binaries or build yourself (under Windows you may use vcpkg with `vcpkg install freetype`, `vcpkg integrate install`).
 2. Add imgui_freetype.h/cpp alongside your imgui sources.
 3. Include imgui_freetype.h after imgui.h.
 4. Call `ImGuiFreeType::BuildFontAtlas()` *BEFORE* calling `ImFontAtlas::GetTexDataAsRGBA32()` or `ImFontAtlas::Build()` (so normal Build() won't be called):
diff --git a/misc/freetype/imgui_freetype.cpp b/misc/freetype/imgui_freetype.cpp
index fb2b399..be41835 100644
--- a/misc/freetype/imgui_freetype.cpp
+++ b/misc/freetype/imgui_freetype.cpp
@@ -300,7 +300,7 @@
     int                 DstIndex;           // Index into atlas->Fonts[] and dst_tmp_array[]
     int                 GlyphsHighest;      // Highest requested codepoint
     int                 GlyphsCount;        // Glyph count (excluding missing glyphs and glyphs already set by an earlier source font)
-    ImBoolVector        GlyphsSet;          // Glyph bit map (random access, 1-bit per codepoint. This will be a maximum of 8KB)
+    ImBitVector         GlyphsSet;          // Glyph bit map (random access, 1-bit per codepoint. This will be a maximum of 8KB)
     ImVector<ImFontBuildSrcGlyphFT>   GlyphsList;
 };
 
@@ -310,7 +310,7 @@
     int                 SrcCount;           // Number of source fonts targeting this destination font.
     int                 GlyphsHighest;
     int                 GlyphsCount;
-    ImBoolVector        GlyphsSet;          // This is used to resolve collision when multiple sources are merged into a same destination font.
+    ImBitVector         GlyphsSet;          // This is used to resolve collision when multiple sources are merged into a same destination font.
 };
 
 bool ImFontAtlasBuildWithFreeType(FT_Library ft_library, ImFontAtlas* atlas, unsigned int extra_flags)
@@ -370,14 +370,14 @@
     {
         ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
         ImFontBuildDstDataFT& dst_tmp = dst_tmp_array[src_tmp.DstIndex];
-        src_tmp.GlyphsSet.Resize(src_tmp.GlyphsHighest + 1);
+        src_tmp.GlyphsSet.Create(src_tmp.GlyphsHighest + 1);
         if (dst_tmp.GlyphsSet.Storage.empty())
-            dst_tmp.GlyphsSet.Resize(dst_tmp.GlyphsHighest + 1);
+            dst_tmp.GlyphsSet.Create(dst_tmp.GlyphsHighest + 1);
 
         for (const ImWchar* src_range = src_tmp.SrcRanges; src_range[0] && src_range[1]; src_range += 2)
             for (int codepoint = src_range[0]; codepoint <= src_range[1]; codepoint++)
             {
-                if (dst_tmp.GlyphsSet.GetBit(codepoint))    // Don't overwrite existing glyphs. We could make this an option (e.g. MergeOverwrite)
+                if (dst_tmp.GlyphsSet.TestBit(codepoint))    // Don't overwrite existing glyphs. We could make this an option (e.g. MergeOverwrite)
                     continue;
                 uint32_t glyph_index = FT_Get_Char_Index(src_tmp.Font.Face, codepoint); // It is actually in the font? (FIXME-OPT: We are not storing the glyph_index..)
                 if (glyph_index == 0)
@@ -386,8 +386,8 @@
                 // Add to avail set/counters
                 src_tmp.GlyphsCount++;
                 dst_tmp.GlyphsCount++;
-                src_tmp.GlyphsSet.SetBit(codepoint, true);
-                dst_tmp.GlyphsSet.SetBit(codepoint, true);
+                src_tmp.GlyphsSet.SetBit(codepoint);
+                dst_tmp.GlyphsSet.SetBit(codepoint);
                 total_glyphs_count++;
             }
     }
@@ -398,13 +398,13 @@
         ImFontBuildSrcDataFT& src_tmp = src_tmp_array[src_i];
         src_tmp.GlyphsList.reserve(src_tmp.GlyphsCount);
 
-        IM_ASSERT(sizeof(src_tmp.GlyphsSet.Storage.Data[0]) == sizeof(int));
-        const int* it_begin = src_tmp.GlyphsSet.Storage.begin();
-        const int* it_end = src_tmp.GlyphsSet.Storage.end();
-        for (const int* it = it_begin; it < it_end; it++)
-            if (int entries_32 = *it)
-                for (int bit_n = 0; bit_n < 32; bit_n++)
-                    if (entries_32 & (1 << bit_n))
+        IM_ASSERT(sizeof(src_tmp.GlyphsSet.Storage.Data[0]) == sizeof(ImU32));
+        const ImU32* it_begin = src_tmp.GlyphsSet.Storage.begin();
+        const ImU32* it_end = src_tmp.GlyphsSet.Storage.end();
+        for (const ImU32* it = it_begin; it < it_end; it++)
+            if (ImU32 entries_32 = *it)
+                for (ImU32 bit_n = 0; bit_n < 32; bit_n++)
+                    if (entries_32 & ((ImU32)1 << bit_n))
                     {
                         ImFontBuildSrcGlyphFT src_glyph;
                         memset(&src_glyph, 0, sizeof(src_glyph));