ImFont: Rearranged members toward an optimal CalcTextSize() loop. Rem…

…oved comments from destructor. Made constructor more explicit.

imgui.h

@@ -2078,24 +2078,26 @@ struct ImFontAtlas
 // ImFontAtlas automatically loads a default embedded font for you when you call GetTexDataAsAlpha8() or GetTexDataAsRGBA32().
 struct ImFont
 {
-    // Members: Hot ~62/78 bytes
-    float                       FontSize;           // <user set>   // Height of characters, set during loading (don't change after loading)
-    float                       Scale;              // = 1.f        // Base font scale, multiplied by the per-window font scale which you can adjust with SetWindowFontScale()
-    ImVec2                      DisplayOffset;      // = (0.f,0.f)  // Offset font rendering by xx pixels
-    ImVector<ImFontGlyph>       Glyphs;             //              // All glyphs.
-    ImVector<float>             IndexAdvanceX;      //              // Sparse. Glyphs->AdvanceX in a directly indexable way (more cache-friendly, for CalcTextSize functions which are often bottleneck in large UI).
-    ImVector<ImWchar>           IndexLookup;        //              // Sparse. Index glyphs by Unicode code-point.
-    const ImFontGlyph*          FallbackGlyph;      // == FindGlyph(FontFallbackChar)
-    float                       FallbackAdvanceX;   // == FallbackGlyph->AdvanceX
-    ImWchar                     FallbackChar;       // = '?'        // Replacement glyph if one isn't found. Only set via SetFallbackChar()
-
-    // Members: Cold ~18/26 bytes
-    short                       ConfigDataCount;    // ~ 1          // Number of ImFontConfig involved in creating this font. Bigger than 1 when merging multiple font sources into one ImFont.
-    ImFontConfig*               ConfigData;         //              // Pointer within ContainerAtlas->ConfigData
-    ImFontAtlas*                ContainerAtlas;     //              // What we has been loaded into
-    float                       Ascent, Descent;    //              // Ascent: distance from top to bottom of e.g. 'A' [0..FontSize]
-    bool                        DirtyLookupTables;
-    int                         MetricsTotalSurface;//              // Total surface in pixels to get an idea of the font rasterization/texture cost (not exact, we approximate the cost of padding between glyphs)
+    // Members: Hot ~24/32 bytes (for CalcTextSize)
+    ImVector<float>             IndexAdvanceX;      // 12/16 // out //            // Sparse. Glyphs->AdvanceX in a directly indexable way (more cache-friendly, for CalcTextSize functions which are often bottleneck in large UI).
+    float                       FontSize;           // 4     // in  // <user set> // Height of characters, set during loading (don't change after loading)
+    float                       FallbackAdvanceX;   // 4     // out // = FallbackGlyph->AdvanceX
+    ImWchar                     FallbackChar;       // 2     // in  // = '?'      // Replacement glyph if one isn't found. Only set via SetFallbackChar()
+
+    // Members: Hot ~36/48 bytes (for CalcTextSize + render loop)
+    ImVector<ImWchar>           IndexLookup;        // 12-16 // out //            // Sparse. Index glyphs by Unicode code-point.
+    ImVector<ImFontGlyph>       Glyphs;             // 12-16 // out //            // All glyphs.
+    ImVec2                      DisplayOffset;      // 8     // in  // = (0,0)    // Offset font rendering by xx pixels
+    const ImFontGlyph*          FallbackGlyph;      // 4-8   // out // = FindGlyph(FontFallbackChar)
+
+    // Members: Cold ~28/40 bytes
+    ImFontAtlas*                ContainerAtlas;     // 4-8   // out //            // What we has been loaded into
+    ImFontConfig*               ConfigData;         // 4-8   // in  //            // Pointer within ContainerAtlas->ConfigData
+    short                       ConfigDataCount;    // 2     // in  // ~ 1        // Number of ImFontConfig involved in creating this font. Bigger than 1 when merging multiple font sources into one ImFont.
+    bool                        DirtyLookupTables;  // 1     // out //
+    float                       Scale;              // 4     // in  // = 1.f       // Base font scale, multiplied by the per-window font scale which you can adjust with SetWindowFontScale()
+    float                       Ascent, Descent;    // 8     // out               // Ascent: distance from top to bottom of e.g. 'A' [0..FontSize]
+    int                         MetricsTotalSurface;// 4     // out               // Total surface in pixels to get an idea of the font rasterization/texture cost (not exact, we approximate the cost of padding between glyphs)
 
     // Methods
     IMGUI_API ImFont();

imgui_draw.cpp

@@ -2390,38 +2390,36 @@ void ImFontGlyphRangesBuilder::BuildRanges(ImVector<ImWchar>* out_ranges)
 
 ImFont::ImFont()
 {
-    Scale = 1.0f;
+    FontSize = 0.0f;
+    FallbackAdvanceX = 0.0f;
     FallbackChar = (ImWchar)'?';
     DisplayOffset = ImVec2(0.0f, 0.0f);
-    ClearOutputData();
+    FallbackGlyph = NULL;
+    ContainerAtlas = NULL;
+    ConfigData = NULL;
+    ConfigDataCount = 0;
+    DirtyLookupTables = false;
+    Scale = 1.0f;
+    Ascent = Descent = 0.0f;
+    MetricsTotalSurface = 0;
 }
 
 ImFont::~ImFont()
 {
-    // Invalidate active font so that the user gets a clear crash instead of a dangling pointer.
-    // If you want to delete fonts you need to do it between Render() and NewFrame().
-    // FIXME-CLEANUP
-    /*
-    ImGuiContext& g = *GImGui;
-    if (g.Font == this)
-        g.Font = NULL;
-    */
     ClearOutputData();
 }
 
 void    ImFont::ClearOutputData()
 {
     FontSize = 0.0f;
+    FallbackAdvanceX = 0.0f;
     Glyphs.clear();
     IndexAdvanceX.clear();
     IndexLookup.clear();
     FallbackGlyph = NULL;
-    FallbackAdvanceX = 0.0f;
-    ConfigDataCount = 0;
-    ConfigData = NULL;
     ContainerAtlas = NULL;
-    Ascent = Descent = 0.0f;
     DirtyLookupTables = true;
+    Ascent = Descent = 0.0f;
     MetricsTotalSurface = 0;
 }