Docs: better promote IMGUI_DEFINE_MATH_OPERATORS. (#6164, #6137, #5966,

#2832)

imgui.h

@@ -5,6 +5,7 @@
 // - See links below.
 // - Call and read ImGui::ShowDemoWindow() in imgui_demo.cpp. All applications in examples/ are doing that.
 // - Read top of imgui.cpp for more details, links and comments.
+// - Add '#define IMGUI_DEFINE_MATH_OPERATORS' before including this file (or in imconfig.h) to access courtesy maths operators for ImVec2 and ImVec4.
 
 // Resources:
 // - FAQ ........................ https://dearimgui.com/faq (in repository as docs/FAQ.md)
@@ -280,8 +281,8 @@ typedef void*   (*ImGuiMemAllocFunc)(size_t sz, void* user_data);
 typedef void    (*ImGuiMemFreeFunc)(void* ptr, void* user_data);                // Function signature for ImGui::SetAllocatorFunctions()
 
 // ImVec2: 2D vector used to store positions, sizes etc. [Compile-time configurable type]
-// This is a frequently used type in the API. Consider using IM_VEC2_CLASS_EXTRA to create implicit cast from/to our preferred type.
-// Add '#define IMGUI_DEFINE_MATH_OPERATORS' in your imconfig.h file to benefit from courtesy maths operators for those types.
+// - This is a frequently used type in the API. Consider using IM_VEC2_CLASS_EXTRA to create implicit cast from/to our preferred type.
+// - Add '#define IMGUI_DEFINE_MATH_OPERATORS' before including this file (or in imconfig.h) to access courtesy maths operators for ImVec2 and ImVec4.
 IM_MSVC_RUNTIME_CHECKS_OFF
 struct ImVec2
 {
@@ -2664,7 +2665,7 @@ struct ImGuiListClipper
 // Helpers: ImVec2/ImVec4 operators
 // - It is important that we are keeping those disabled by default so they don't leak in user space.
 // - This is in order to allow user enabling implicit cast operators between ImVec2/ImVec4 and their own types (using IM_VEC2_CLASS_EXTRA in imconfig.h)
-// - You can use '#define IMGUI_DEFINE_MATH_OPERATORS' to import our operators, provided as a courtesy.
+// - Add '#define IMGUI_DEFINE_MATH_OPERATORS' before including this file (or in imconfig.h) to access courtesy maths operators for ImVec2 and ImVec4.
 #ifdef IMGUI_DEFINE_MATH_OPERATORS
 #define IMGUI_DEFINE_MATH_OPERATORS_IMPLEMENTED
 IM_MSVC_RUNTIME_CHECKS_OFF