Update Dear ImGui to 1.71

CHANGELOG.md

@@ -6,6 +6,7 @@
 
   * Fixed memory leaks from dart::gui::osg::Viewer: [#1349](https://github.com/dartsim/dart/pull/1349)
   * Added point rendering mode to PointCloudShape: [#1351](https://github.com/dartsim/dart/pull/1351), [#1355](https://github.com/dartsim/dart/pull/1355)
+  * Updated ImGui to 1.71: [#1362](https://github.com/dartsim/dart/pull/1362)
 
 * dartpy
 

dart/external/imgui/CMakeLists.txt

@@ -14,6 +14,9 @@ target_include_directories(${target_name}
   PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}>
 )
 target_link_libraries(${target_name} PUBLIC OpenGL::GL)
+if(APPLE)
+  target_link_libraries(${target_name} PUBLIC "-framework Cocoa")
+endif()
 
 if(CMAKE_COMPILER_IS_GNUCXX)
   target_compile_options(${target_name} PRIVATE -w)

dart/external/imgui/imconfig.h

@@ -3,10 +3,10 @@
 // Runtime options (clipboard callbacks, enabling various features, etc.) can generally be set via the ImGuiIO structure.
 // You can use ImGui::SetAllocatorFunctions() before calling ImGui::CreateContext() to rewire memory allocation functions.
 //-----------------------------------------------------------------------------
-// A) You may edit imconfig.h (and not overwrite it when updating imgui, or maintain a patch/branch with your modifications to imconfig.h)
+// A) You may edit imconfig.h (and not overwrite it when updating Dear ImGui, or maintain a patch/branch with your modifications to imconfig.h)
 // B) or add configuration directives in your own file and compile with #define IMGUI_USER_CONFIG "myfilename.h"
-// If you do so you need to make sure that configuration settings are defined consistently _everywhere_ dear imgui is used, which include
-// the imgui*.cpp files but also _any_ of your code that uses imgui. This is because some compile-time options have an affect on data structures.
+// If you do so you need to make sure that configuration settings are defined consistently _everywhere_ Dear ImGui is used, which include
+// the imgui*.cpp files but also _any_ of your code that uses Dear ImGui. This is because some compile-time options have an affect on data structures.
 // Defining those options in imconfig.h will ensure every compilation unit gets to see the same data structure layouts.
 // Call IMGUI_CHECKVERSION() from your .cpp files to verify that the data structures your files are using are matching the ones imgui.cpp is using.
 //-----------------------------------------------------------------------------
@@ -17,21 +17,23 @@
 //#define IM_ASSERT(_EXPR)  MyAssert(_EXPR)
 //#define IM_ASSERT(_EXPR)  ((void)(_EXPR))     // Disable asserts
 
-//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows.
+//---- Define attributes of all API symbols declarations, e.g. for DLL under Windows 
+// Using dear imgui via a shared library is not recommended, because of function call overhead and because we don't guarantee backward nor forward ABI compatibility.
 //#define IMGUI_API __declspec( dllexport )
 //#define IMGUI_API __declspec( dllimport )
 
 //---- Don't define obsolete functions/enums names. Consider enabling from time to time after updating to avoid using soon-to-be obsolete function/names.
 //#define IMGUI_DISABLE_OBSOLETE_FUNCTIONS
 
 //---- Don't implement demo windows functionality (ShowDemoWindow()/ShowStyleEditor()/ShowUserGuide() methods will be empty)
-//---- It is very strongly recommended to NOT disable the demo windows during development. Please read the comments in imgui_demo.cpp.
+// It is very strongly recommended to NOT disable the demo windows during development. Please read the comments in imgui_demo.cpp.
 //#define IMGUI_DISABLE_DEMO_WINDOWS
 
 //---- Don't implement some functions to reduce linkage requirements.
 //#define IMGUI_DISABLE_WIN32_DEFAULT_CLIPBOARD_FUNCTIONS   // [Win32] Don't implement default clipboard handler. Won't use and link with OpenClipboard/GetClipboardData/CloseClipboard etc.
 //#define IMGUI_DISABLE_WIN32_DEFAULT_IME_FUNCTIONS         // [Win32] Don't implement default IME handler. Won't use and link with ImmGetContext/ImmSetCompositionWindow.
-//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function.
+//#define IMGUI_DISABLE_WIN32_FUNCTIONS                     // [Win32] Won't use and link with any Win32 function (clipboard, ime).
+//#define IMGUI_DISABLE_OSX_FUNCTIONS                       // [OSX] Won't use and link with any OSX function (clipboard).
 //#define IMGUI_DISABLE_FORMAT_STRING_FUNCTIONS             // Don't implement ImFormatString/ImFormatStringV so you can implement them yourself if you don't want to link with vsnprintf.
 //#define IMGUI_DISABLE_MATH_FUNCTIONS                      // Don't implement ImFabs/ImSqrt/ImPow/ImFmod/ImCos/ImSin/ImAcos/ImAtan2 wrapper so you can implement them yourself. Declare your prototypes in imconfig.h.
 //#define IMGUI_DISABLE_DEFAULT_ALLOCATORS                  // Don't implement default allocators calling malloc()/free() to avoid linking with them. You will need to call ImGui::SetAllocatorFunctions().
@@ -61,9 +63,18 @@
         operator MyVec4() const { return MyVec4(x,y,z,w); }
 */
 
-//---- Use 32-bit vertex indices (default is 16-bit) to allow meshes with more than 64K vertices. Render function needs to support it.
+//---- Using 32-bits vertex indices (default is 16-bits) is one way to allow large meshes with more than 64K vertices. 
+// Your renderer back-end will need to support it (most example renderer back-ends support both 16/32-bits indices).
+// Another way to allow large meshes while keeping 16-bits indices is to handle ImDrawCmd::VtxOffset in your renderer. 
+// Read about ImGuiBackendFlags_RendererHasVtxOffset for details.
 //#define ImDrawIdx unsigned int
 
+//---- Override ImDrawCallback signature (will need to modify renderer back-ends accordingly)
+//struct ImDrawList;
+//struct ImDrawCmd;
+//typedef void (*MyImDrawCallback)(const ImDrawList* draw_list, const ImDrawCmd* cmd, void* my_renderer_user_data);
+//#define ImDrawCallback MyImDrawCallback
+
 //---- Tip: You can add extra functions within the ImGui:: namespace, here or in your own headers files.
 /*
 namespace ImGui