ImGuiTextBuffer: Added append() function (unformatted).

docs/CHANGELOG.txt

@@ -37,6 +37,7 @@ Other Changes:
 - Added .editorconfig file for text editors to standardize using spaces. (#2038) [@kudaba]
 - ImDrawList: Fixed AddCircle(), AddCircleFilled() angle step being off, which was visible when drawing a "circle"
   with a small number of segments (e.g. an hexagon). (#2287) [@baktery]
+- ImGuiTextBuffer: Added append() function (unformatted).
 - ImFontAtlas: Added 0x2000-0x206F general punctuation range to default ChineseFull/ChineseSimplifiedCommon ranges. (#2093)
 - ImFontAtlas: FreeType: Added support for imgui allocators + custom FreeType only SetAllocatorFunctions. (#2285) [@Vuhdo]
 - Examples: Win32: Using GetForegroundWindow()+IsChild() instead of GetActiveWindow() to be compatible with windows created 

imgui.cpp

@@ -2097,6 +2097,32 @@ bool ImGuiTextFilter::PassFilter(const char* text, const char* text_end) const
 
 char ImGuiTextBuffer::EmptyString[1] = { 0 };
 
+void ImGuiTextBuffer::append(const char* str, const char* str_end)
+{
+    int len = str_end ? (int)(str_end - str) : (int)strlen(str);
+
+    // Add zero-terminator the first time
+    const int write_off = (Buf.Size != 0) ? Buf.Size : 1;
+    const int needed_sz = write_off + len;
+    if (write_off + len >= Buf.Capacity)
+    {
+        int new_capacity = Buf.Capacity * 2;
+        Buf.reserve(needed_sz > new_capacity ? needed_sz : new_capacity);
+    }
+
+    Buf.resize(needed_sz);
+    memcpy(&Buf[write_off - 1], str, (size_t)len);
+    Buf[write_off - 1 + len] = 0;
+}
+
+void ImGuiTextBuffer::appendf(const char* fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    appendfv(fmt, args);
+    va_end(args);
+}
+
 // Helper: Text buffer for logging/accumulating text
 void ImGuiTextBuffer::appendfv(const char* fmt, va_list args)
 {
@@ -2115,8 +2141,8 @@ void ImGuiTextBuffer::appendfv(const char* fmt, va_list args)
     const int needed_sz = write_off + len;
     if (write_off + len >= Buf.Capacity)
     {
-        int double_capacity = Buf.Capacity * 2;
-        Buf.reserve(needed_sz > double_capacity ? needed_sz : double_capacity);
+        int new_capacity = Buf.Capacity * 2;
+        Buf.reserve(needed_sz > new_capacity ? needed_sz : new_capacity);
     }
 
     Buf.resize(needed_sz);
@@ -2124,14 +2150,6 @@ void ImGuiTextBuffer::appendfv(const char* fmt, va_list args)
     va_end(args_copy);
 }
 
-void ImGuiTextBuffer::appendf(const char* fmt, ...)
-{
-    va_list args;
-    va_start(args, fmt);
-    appendfv(fmt, args);
-    va_end(args);
-}
-
 //-----------------------------------------------------------------------------
 // [SECTION] ImGuiListClipper
 // This is currently not as flexible/powerful as it should be, needs some rework (see TODO)

imgui.h

@@ -1586,6 +1586,7 @@ struct ImGuiTextBuffer
     void                clear()                 { Buf.clear(); }
     void                reserve(int capacity)   { Buf.reserve(capacity); }
     const char*         c_str() const           { return Buf.Data ? Buf.Data : EmptyString; }
+    IMGUI_API void      append(const char* str, const char* str_end = NULL);
     IMGUI_API void      appendf(const char* fmt, ...) IM_FMTARGS(2);
     IMGUI_API void      appendfv(const char* fmt, va_list args) IM_FMTLIST(2);
 };