Merge miscellaneous small changes to reduce drift with texture update…

… branch. - ImGuiDebugLogFlags_EventFont is yet unused.
ocornut · Nov 20, 2024 · 20360e0 · 20360e0
1 parent 551b6c4
commit 20360e0
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Showing 6 changed files with 95 additions and 71 deletions.
diff --git a/backends/imgui_impl_opengl3.cpp b/backends/imgui_impl_opengl3.cpp
@@ -164,6 +164,7 @@
 // In the rest of your app/engine, you can use another loader of your choice (gl3w, glew, glad, glbinding, glext, glLoadGen, etc.).
 // If you happen to be developing a new feature for this backend (imgui_impl_opengl3.cpp):
 // - You may need to regenerate imgui_impl_opengl3_loader.h to add new symbols. See https://github.com/dearimgui/gl3w_stripped
+//   Typically you would run: python3 ./gl3w_gen.py --output ../imgui/backends/imgui_impl_opengl3_loader.h --ref ../imgui/backends/imgui_impl_opengl3.cpp ./extra_symbols.txt
 // - You can temporarily use an unstripped version. See https://github.com/dearimgui/gl3w_stripped/releases
 // Changes to this backend using new APIs should be accompanied by a regenerated stripped loader version.
 #define IMGL3W_IMPL
@@ -689,7 +690,7 @@ bool ImGui_ImplOpenGL3_CreateFontsTexture()
 #endif
     GL_CALL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixels));
 
-    // Store our identifier
+    // Store identifier
     io.Fonts->SetTexID((ImTextureID)(intptr_t)bd->FontTexture);
 
     // Restore state

diff --git a/imgui.cpp b/imgui.cpp
@@ -4010,7 +4010,7 @@ ImGuiContext::ImGuiContext(ImFontAtlas* shared_font_atlas)
     StackSizesInBeginForCurrentWindow = NULL;
 
     DebugDrawIdConflictsCount = 0;
-    DebugLogFlags = ImGuiDebugLogFlags_EventError | ImGuiDebugLogFlags_OutputToTTY;
+    DebugLogFlags = ImGuiDebugLogFlags_EventError | ImGuiDebugLogFlags_OutputToTTY | ImGuiDebugLogFlags_EventFont;
     DebugLocateId = 0;
     DebugLogSkippedErrors = 0;
     DebugLogAutoDisableFlags = ImGuiDebugLogFlags_None;
@@ -4226,8 +4226,8 @@ ImGuiWindow::ImGuiWindow(ImGuiContext* ctx, const char* name) : DrawListInst(NUL
     FontWindowScale = 1.0f;
     SettingsOffset = -1;
     DrawList = &DrawListInst;
-    DrawList->_Data = &Ctx->DrawListSharedData;
     DrawList->_OwnerName = Name;
+    DrawList->_Data = &Ctx->DrawListSharedData;
     NavPreferredScoringPosRel[0] = NavPreferredScoringPosRel[1] = ImVec2(FLT_MAX, FLT_MAX);
 }
 
@@ -5025,7 +5025,7 @@ void ImGui::UpdateHoveredWindowAndCaptureFlags()
     io.WantTextInput = (g.WantTextInputNextFrame != -1) ? (g.WantTextInputNextFrame != 0) : false;
 }
 
-// Calling SetupDrawListSharedData() is followed by SetCurrentFont() which sets up the remaining data.
+// Called once a frame. Followed by SetCurrentFont() which sets up the remaining data.
 static void SetupDrawListSharedData()
 {
     ImGuiContext& g = *GImGui;
@@ -15180,6 +15180,17 @@ void ImGui::UpdateDebugToolFlashStyleColor()
         DebugFlashStyleColorStop();
 }
 
+static const char* FormatTextureIDForDebugDisplay(char* buf, int buf_size, ImTextureID tex_id)
+{
+    union { void* ptr; int integer; } tex_id_opaque;
+    memcpy(&tex_id_opaque, &tex_id, ImMin(sizeof(void*), sizeof(tex_id)));
+    if (sizeof(tex_id) >= sizeof(void*))
+        ImFormatString(buf, buf_size, "0x%p", tex_id_opaque.ptr);
+    else
+        ImFormatString(buf, buf_size, "0x%04X", tex_id_opaque.integer);
+    return buf;
+}
+
 // Avoid naming collision with imgui_demo.cpp's HelpMarker() for unity builds.
 static void MetricsHelpMarker(const char* desc)
 {
@@ -15868,16 +15879,6 @@ void ImGui::DebugNodeColumns(ImGuiOldColumns* columns)
     TreePop();
 }
 
-static void FormatTextureIDForDebugDisplay(char* buf, int buf_size, ImTextureID tex_id)
-{
-    union { void* ptr; int integer; } tex_id_opaque;
-    memcpy(&tex_id_opaque, &tex_id, ImMin(sizeof(void*), sizeof(tex_id)));
-    if (sizeof(tex_id) >= sizeof(void*))
-        ImFormatString(buf, buf_size, "0x%p", tex_id_opaque.ptr);
-    else
-        ImFormatString(buf, buf_size, "0x%04X", tex_id_opaque.integer);
-}
-
 // [DEBUG] Display contents of ImDrawList
 void ImGui::DebugNodeDrawList(ImGuiWindow* window, ImGuiViewportP* viewport, const ImDrawList* draw_list, const char* label)
 {
@@ -16379,6 +16380,7 @@ void ImGui::ShowDebugLogWindow(bool* p_open)
     ShowDebugLogFlag("Clipper", ImGuiDebugLogFlags_EventClipper);
     ShowDebugLogFlag("Focus", ImGuiDebugLogFlags_EventFocus);
     ShowDebugLogFlag("IO", ImGuiDebugLogFlags_EventIO);
+    //ShowDebugLogFlag("Font", ImGuiDebugLogFlags_EventFont);
     ShowDebugLogFlag("Nav", ImGuiDebugLogFlags_EventNav);
     ShowDebugLogFlag("Popup", ImGuiDebugLogFlags_EventPopup);
     ShowDebugLogFlag("Selection", ImGuiDebugLogFlags_EventSelection);

diff --git a/imgui.h b/imgui.h
@@ -2309,6 +2309,7 @@ struct ImGuiIO
     // (the imgui_impl_xxxx backend files are setting those up for you)
     //------------------------------------------------------------------
 
+    // Nowadays those would be stored in ImGuiPlatformIO but we are leaving them here for legacy reasons.
     // Optional: Platform/Renderer backend name (informational only! will be displayed in About Window) + User data for backend/wrappers to store their own stuff.
     const char* BackendPlatformName;            // = NULL
     const char* BackendRendererName;            // = NULL
@@ -3064,10 +3065,11 @@ struct ImDrawList
     float                   _FringeScale;       // [Internal] anti-alias fringe is scaled by this value, this helps to keep things sharp while zooming at vertex buffer content
     const char*             _OwnerName;         // Pointer to owner window's name for debugging
 
-    // If you want to create ImDrawList instances, pass them ImGui::GetDrawListSharedData() or create and use your own ImDrawListSharedData (so you can use ImDrawList without ImGui)
-    ImDrawList(ImDrawListSharedData* shared_data) { memset(this, 0, sizeof(*this)); _Data = shared_data; }
-
-    ~ImDrawList() { _ClearFreeMemory(); }
+    // If you want to create ImDrawList instances, pass them ImGui::GetDrawListSharedData().
+    // (advanced: you may create and use your own ImDrawListSharedData so you can use ImDrawList without ImGui, but that's more involved)
+    IMGUI_API ImDrawList(ImDrawListSharedData* shared_data);
+    IMGUI_API ~ImDrawList();
+
     IMGUI_API void  PushClipRect(const ImVec2& clip_rect_min, const ImVec2& clip_rect_max, bool intersect_with_current_clip_rect = false);  // Render-level scissoring. This is passed down to your render function but not used for CPU-side coarse clipping. Prefer using higher-level ImGui::PushClipRect() to affect logic (hit-testing and widget culling)
     IMGUI_API void  PushClipRectFullScreen();
     IMGUI_API void  PopClipRect();
@@ -3277,14 +3279,16 @@ struct ImFontGlyphRangesBuilder
 // See ImFontAtlas::AddCustomRectXXX functions.
 struct ImFontAtlasCustomRect
 {
-    unsigned short  Width, Height;  // Input    // Desired rectangle dimension
     unsigned short  X, Y;           // Output   // Packed position in Atlas
+
+    // [Internal]
+    unsigned short  Width, Height;  // Input    // Desired rectangle dimension
     unsigned int    GlyphID : 31;   // Input    // For custom font glyphs only (ID < 0x110000)
     unsigned int    GlyphColored : 1; // Input  // For custom font glyphs only: glyph is colored, removed tinting.
     float           GlyphAdvanceX;  // Input    // For custom font glyphs only: glyph xadvance
     ImVec2          GlyphOffset;    // Input    // For custom font glyphs only: glyph display offset
     ImFont*         Font;           // Input    // For custom font glyphs only: target font
-    ImFontAtlasCustomRect()         { Width = Height = 0; X = Y = 0xFFFF; GlyphID = 0; GlyphColored = 0; GlyphAdvanceX = 0.0f; GlyphOffset = ImVec2(0, 0); Font = NULL; }
+    ImFontAtlasCustomRect()         { X = Y = 0xFFFF; Width = Height = 0; GlyphID = 0; GlyphColored = 0; GlyphAdvanceX = 0.0f; GlyphOffset = ImVec2(0, 0); Font = NULL; }
     bool IsPacked() const           { return X != 0xFFFF; }
 };
 
@@ -3431,8 +3435,9 @@ struct ImFont
     const ImFontGlyph*          FallbackGlyph;      // 4-8   // out // = FindGlyph(FontFallbackChar)
 
     // Members: Cold ~32/40 bytes
+    // Conceptually ConfigData[] is the list of font sources merged to create this font.
     ImFontAtlas*                ContainerAtlas;     // 4-8   // out //            // What we has been loaded into
-    const ImFontConfig*         ConfigData;         // 4-8   // in  //            // Pointer within ContainerAtlas->ConfigData
+    const ImFontConfig*         ConfigData;         // 4-8   // in  //            // Pointer within ContainerAtlas->ConfigData to ConfigDataCount instances
     short                       ConfigDataCount;    // 2     // in  // ~ 1        // Number of ImFontConfig involved in creating this font. Bigger than 1 when merging multiple font sources into one ImFont.
     ImWchar                     FallbackChar;       // 2     // out // = FFFD/'?' // Character used if a glyph isn't found.
     ImWchar                     EllipsisChar;       // 2     // out // = '...'/'.'// Character used for ellipsis rendering.

diff --git a/imgui_draw.cpp b/imgui_draw.cpp
@@ -14,7 +14,7 @@ Index of this file:
 // [SECTION] Helpers ShadeVertsXXX functions
 // [SECTION] ImFontConfig
 // [SECTION] ImFontAtlas
-// [SECTION] ImFontAtlas glyph ranges helpers
+// [SECTION] ImFontAtlas: glyph ranges helpers
 // [SECTION] ImFontGlyphRangesBuilder
 // [SECTION] ImFont
 // [SECTION] ImGui Internal Render Helpers
@@ -394,6 +394,17 @@ void ImDrawListSharedData::SetCircleTessellationMaxError(float max_error)
     ArcFastRadiusCutoff = IM_DRAWLIST_CIRCLE_AUTO_SEGMENT_CALC_R(IM_DRAWLIST_ARCFAST_SAMPLE_MAX, CircleSegmentMaxError);
 }
 
+ImDrawList::ImDrawList(ImDrawListSharedData* shared_data)
+{
+    memset(this, 0, sizeof(*this)); 
+    _Data = shared_data;
+}
+
+ImDrawList::~ImDrawList()
+{
+    _ClearFreeMemory();
+}
+
 // Initialize before use in a new frame. We always have a command ready in the buffer.
 // In the majority of cases, you would want to call PushClipRect() and PushTextureID() after this.
 void ImDrawList::_ResetForNewFrame()
@@ -2528,6 +2539,7 @@ ImFont* ImFontAtlas::AddFont(const ImFontConfig* font_cfg)
     IM_ASSERT(font_cfg->FontData != NULL && font_cfg->FontDataSize > 0);
     IM_ASSERT(font_cfg->SizePixels > 0.0f && "Is ImFontConfig struct correctly initialized?");
     IM_ASSERT(font_cfg->OversampleH > 0 && font_cfg->OversampleV > 0 && "Is ImFontConfig struct correctly initialized?");
+    IM_ASSERT(font_cfg->RasterizerDensity > 0.0f);
 
     // Create new font
     if (!font_cfg->MergeMode)
@@ -2546,9 +2558,16 @@ ImFont* ImFontAtlas::AddFont(const ImFontConfig* font_cfg)
         memcpy(new_font_cfg.FontData, font_cfg->FontData, (size_t)new_font_cfg.FontDataSize);
     }
 
+    // Round font size
+    // - We started rounding in 1.90 WIP (18991) as our layout system currently doesn't support non-rounded font size well yet.
+    // - Note that using io.FontGlobalScale or SetWindowFontScale(), with are legacy-ish, partially supported features, can still lead to unrounded sizes.
+    // - We may support it better later and remove this rounding.
+    new_font_cfg.SizePixels = ImTrunc(new_font_cfg.SizePixels);
+
     if (new_font_cfg.DstFont->EllipsisChar == (ImWchar)-1)
         new_font_cfg.DstFont->EllipsisChar = font_cfg->EllipsisChar;
 
+    // Pointers to ConfigData and BuilderData are otherwise dangling
     ImFontAtlasUpdateConfigDataPointers(this);
 
     // Invalidate texture
@@ -3163,35 +3182,35 @@ static void ImFontAtlasBuildRenderDefaultTexData(ImFontAtlas* atlas)
     IM_ASSERT(r->IsPacked());
 
     const int w = atlas->TexWidth;
-    if (!(atlas->Flags & ImFontAtlasFlags_NoMouseCursors))
+    if (atlas->Flags & ImFontAtlasFlags_NoMouseCursors)
     {
-        // Render/copy pixels
-        IM_ASSERT(r->Width == FONT_ATLAS_DEFAULT_TEX_DATA_W * 2 + 1 && r->Height == FONT_ATLAS_DEFAULT_TEX_DATA_H);
-        const int x_for_white = r->X;
-        const int x_for_black = r->X + FONT_ATLAS_DEFAULT_TEX_DATA_W + 1;
+        // White pixels only
+        IM_ASSERT(r->Width == 2 && r->Height == 2);
+        const int offset = (int)r->X + (int)r->Y * w;
         if (atlas->TexPixelsAlpha8 != NULL)
         {
-            ImFontAtlasBuildRender8bppRectFromString(atlas, x_for_white, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, '.', 0xFF);
-            ImFontAtlasBuildRender8bppRectFromString(atlas, x_for_black, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, 'X', 0xFF);
+            atlas->TexPixelsAlpha8[offset] = atlas->TexPixelsAlpha8[offset + 1] = atlas->TexPixelsAlpha8[offset + w] = atlas->TexPixelsAlpha8[offset + w + 1] = 0xFF;
         }
         else
         {
-            ImFontAtlasBuildRender32bppRectFromString(atlas, x_for_white, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, '.', IM_COL32_WHITE);
-            ImFontAtlasBuildRender32bppRectFromString(atlas, x_for_black, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, 'X', IM_COL32_WHITE);
+            atlas->TexPixelsRGBA32[offset] = atlas->TexPixelsRGBA32[offset + 1] = atlas->TexPixelsRGBA32[offset + w] = atlas->TexPixelsRGBA32[offset + w + 1] = IM_COL32_WHITE;
         }
     }
     else
     {
-        // Render 4 white pixels
-        IM_ASSERT(r->Width == 2 && r->Height == 2);
-        const int offset = (int)r->X + (int)r->Y * w;
+        // White pixels and mouse cursor
+        IM_ASSERT(r->Width == FONT_ATLAS_DEFAULT_TEX_DATA_W * 2 + 1 && r->Height == FONT_ATLAS_DEFAULT_TEX_DATA_H);
+        const int x_for_white = r->X;
+        const int x_for_black = r->X + FONT_ATLAS_DEFAULT_TEX_DATA_W + 1;
         if (atlas->TexPixelsAlpha8 != NULL)
         {
-            atlas->TexPixelsAlpha8[offset] = atlas->TexPixelsAlpha8[offset + 1] = atlas->TexPixelsAlpha8[offset + w] = atlas->TexPixelsAlpha8[offset + w + 1] = 0xFF;
+            ImFontAtlasBuildRender8bppRectFromString(atlas, x_for_white, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, '.', 0xFF);
+            ImFontAtlasBuildRender8bppRectFromString(atlas, x_for_black, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, 'X', 0xFF);
         }
         else
         {
-            atlas->TexPixelsRGBA32[offset] = atlas->TexPixelsRGBA32[offset + 1] = atlas->TexPixelsRGBA32[offset + w] = atlas->TexPixelsRGBA32[offset + w + 1] = IM_COL32_WHITE;
+            ImFontAtlasBuildRender32bppRectFromString(atlas, x_for_white, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, '.', IM_COL32_WHITE);
+            ImFontAtlasBuildRender32bppRectFromString(atlas, x_for_black, r->Y, FONT_ATLAS_DEFAULT_TEX_DATA_W, FONT_ATLAS_DEFAULT_TEX_DATA_H, FONT_ATLAS_DEFAULT_TEX_DATA_PIXELS, 'X', IM_COL32_WHITE);
         }
     }
     atlas->TexUvWhitePixel = ImVec2((r->X + 0.5f) * atlas->TexUvScale.x, (r->Y + 0.5f) * atlas->TexUvScale.y);
@@ -3205,38 +3224,38 @@ static void ImFontAtlasBuildRenderLinesTexData(ImFontAtlas* atlas)
     // This generates a triangular shape in the texture, with the various line widths stacked on top of each other to allow interpolation between them
     ImFontAtlasCustomRect* r = atlas->GetCustomRectByIndex(atlas->PackIdLines);
     IM_ASSERT(r->IsPacked());
-    for (unsigned int n = 0; n < IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 1; n++) // +1 because of the zero-width row
+    for (int n = 0; n < IM_DRAWLIST_TEX_LINES_WIDTH_MAX + 1; n++) // +1 because of the zero-width row
     {
         // Each line consists of at least two empty pixels at the ends, with a line of solid pixels in the middle
-        unsigned int y = n;
-        unsigned int line_width = n;
-        unsigned int pad_left = (r->Width - line_width) / 2;
-        unsigned int pad_right = r->Width - (pad_left + line_width);
+        int y = n;
+        int line_width = n;
+        int pad_left = (r->Width - line_width) / 2;
+        int pad_right = r->Width - (pad_left + line_width);
 
         // Write each slice
         IM_ASSERT(pad_left + line_width + pad_right == r->Width && y < r->Height); // Make sure we're inside the texture bounds before we start writing pixels
         if (atlas->TexPixelsAlpha8 != NULL)
         {
             unsigned char* write_ptr = &atlas->TexPixelsAlpha8[r->X + ((r->Y + y) * atlas->TexWidth)];
-            for (unsigned int i = 0; i < pad_left; i++)
+            for (int i = 0; i < pad_left; i++)
                 *(write_ptr + i) = 0x00;
 
-            for (unsigned int i = 0; i < line_width; i++)
+            for (int i = 0; i < line_width; i++)
                 *(write_ptr + pad_left + i) = 0xFF;
 
-            for (unsigned int i = 0; i < pad_right; i++)
+            for (int i = 0; i < pad_right; i++)
                 *(write_ptr + pad_left + line_width + i) = 0x00;
         }
         else
         {
             unsigned int* write_ptr = &atlas->TexPixelsRGBA32[r->X + ((r->Y + y) * atlas->TexWidth)];
-            for (unsigned int i = 0; i < pad_left; i++)
+            for (int i = 0; i < pad_left; i++)
                 *(write_ptr + i) = IM_COL32(255, 255, 255, 0);
 
-            for (unsigned int i = 0; i < line_width; i++)
+            for (int i = 0; i < line_width; i++)
                 *(write_ptr + pad_left + i) = IM_COL32_WHITE;
 
-            for (unsigned int i = 0; i < pad_right; i++)
+            for (int i = 0; i < pad_right; i++)
                 *(write_ptr + pad_left + line_width + i) = IM_COL32(255, 255, 255, 0);
         }
 
@@ -3251,13 +3270,6 @@ static void ImFontAtlasBuildRenderLinesTexData(ImFontAtlas* atlas)
 // Note: this is called / shared by both the stb_truetype and the FreeType builder
 void ImFontAtlasBuildInit(ImFontAtlas* atlas)
 {
-    // Round font size
-    // - We started rounding in 1.90 WIP (18991) as our layout system currently doesn't support non-rounded font size well yet.
-    // - Note that using io.FontGlobalScale or SetWindowFontScale(), with are legacy-ish, partially supported features, can still lead to unrounded sizes.
-    // - We may support it better later and remove this rounding.
-    for (ImFontConfig& cfg : atlas->ConfigData)
-       cfg.SizePixels = ImTrunc(cfg.SizePixels);
-
     // Register texture region for mouse cursors or standard white pixels
     if (atlas->PackIdMouseCursors < 0)
     {
@@ -3308,6 +3320,10 @@ void ImFontAtlasBuildFinish(ImFontAtlas* atlas)
     atlas->TexReady = true;
 }
 
+//-------------------------------------------------------------------------
+// [SECTION] ImFontAtlas: glyph ranges helpers
+//-------------------------------------------------------------------------
+
 // Retrieve list of range (2 int per range, values are inclusive)
 const ImWchar*   ImFontAtlas::GetGlyphRangesDefault()
 {
@@ -3369,10 +3385,6 @@ static void UnpackAccumulativeOffsetsIntoRanges(int base_codepoint, const short*
     out_ranges[0] = 0;
 }
 
-//-------------------------------------------------------------------------
-// [SECTION] ImFontAtlas glyph ranges helpers
-//-------------------------------------------------------------------------
-
 const ImWchar*  ImFontAtlas::GetGlyphRangesChineseSimplifiedCommon()
 {
     // Store 2500 regularly used characters for Simplified Chinese.
@@ -3799,8 +3811,9 @@ void ImFont::AddGlyph(const ImFontConfig* cfg, ImWchar codepoint, float x0, floa
         advance_x += cfg->GlyphExtraSpacing.x;
     }
 
+    int glyph_idx = Glyphs.Size;
     Glyphs.resize(Glyphs.Size + 1);
-    ImFontGlyph& glyph = Glyphs.back();
+    ImFontGlyph& glyph = Glyphs[glyph_idx];
     glyph.Codepoint = (unsigned int)codepoint;
     glyph.Visible = (x0 != x1) && (y0 != y1);
     glyph.Colored = false;
@@ -3836,6 +3849,7 @@ void ImFont::AddRemapChar(ImWchar dst, ImWchar src, bool overwrite_dst)
     IndexAdvanceX[dst] = (src < index_size) ? IndexAdvanceX.Data[src] : 1.0f;
 }
 
+// Find glyph, return fallback if missing
 const ImFontGlyph* ImFont::FindGlyph(ImWchar c)
 {
     if (c >= (size_t)IndexLookup.Size)