diff --git a/examples/imgui_impl_opengl2.cpp b/examples/imgui_impl_opengl2.cpp
index ccac3fac..e584c072 100644
--- a/examples/imgui_impl_opengl2.cpp
+++ b/examples/imgui_impl_opengl2.cpp
@@ -27,6 +27,11 @@
 
 #include "imgui.h"
 #include "imgui_impl_opengl2.h"
+#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
+#include <stddef.h>     // intptr_t
+#else
+#include <stdint.h>     // intptr_t
+#endif
 
 // Include OpenGL header (without an OpenGL loader) requires a bit of fiddling
 #if defined(_WIN32) && !defined(APIENTRY)
diff --git a/examples/imgui_impl_opengl3.cpp b/examples/imgui_impl_opengl3.cpp
index b1db4cbe..daa418ad 100644
--- a/examples/imgui_impl_opengl3.cpp
+++ b/examples/imgui_impl_opengl3.cpp
@@ -51,6 +51,11 @@
 #include "imgui.h"
 #include "imgui_impl_opengl3.h"
 #include <stdio.h>
+#if defined(_MSC_VER) && _MSC_VER <= 1500 // MSVC 2008 or earlier
+#include <stddef.h>     // intptr_t
+#else
+#include <stdint.h>     // intptr_t
+#endif
 
 #include <GL/gl3w.h>    // This example is using gl3w to access OpenGL functions. You may use another OpenGL loader/header such as: glew, glext, glad, glLoadGen, etc.
 //#include <glew.h>
diff --git a/imgui.h b/imgui.h
index 6a605e69..0e3ff9d5 100644
--- a/imgui.h
+++ b/imgui.h
@@ -546,9 +546,9 @@ namespace ImGui
     IMGUI_API bool          IsKeyPressed(int user_key_index, bool repeat = true);               // was key pressed (went from !Down to Down). if repeat=true, uses io.KeyRepeatDelay / KeyRepeatRate
     IMGUI_API bool          IsKeyReleased(int user_key_index);                                  // was key released (went from Down to !Down)..
     IMGUI_API int           GetKeyPressedAmount(int key_index, float repeat_delay, float rate); // uses provided repeat rate/delay. return a count, most often 0 or 1 but might be >1 if RepeatRate is small enough that DeltaTime > RepeatRate
-    IMGUI_API bool          IsMouseDown(int button);                                            // is mouse button held
+    IMGUI_API bool          IsMouseDown(int button);                                            // is mouse button held (0=left, 1=right, 2=middle)
     IMGUI_API bool          IsAnyMouseDown();                                                   // is any mouse button held
-    IMGUI_API bool          IsMouseClicked(int button, bool repeat = false);                    // did mouse button clicked (went from !Down to Down)
+    IMGUI_API bool          IsMouseClicked(int button, bool repeat = false);                    // did mouse button clicked (went from !Down to Down) (0=left, 1=right, 2=middle)
     IMGUI_API bool          IsMouseDoubleClicked(int button);                                   // did mouse button double-clicked. a double-click returns false in IsMouseClicked(). uses io.MouseDoubleClickTime.
     IMGUI_API bool          IsMouseReleased(int button);                                        // did mouse button released (went from Down to !Down)
     IMGUI_API bool          IsMouseDragging(int button = 0, float lock_threshold = -1.0f);      // is mouse dragging. if lock_threshold < -1.0f uses io.MouseDraggingThreshold
@@ -1119,7 +1119,7 @@ struct ImGuiIO
     //------------------------------------------------------------------
 
     ImVec2      MousePos;                       // Mouse position, in pixels. Set to ImVec2(-FLT_MAX,-FLT_MAX) if mouse is unavailable (on another screen, etc.)
-    bool        MouseDown[5];                   // Mouse buttons: left, right, middle + extras. ImGui itself mostly only uses left button (BeginPopupContext** are using right button). Others buttons allows us to track if the mouse is being used by your application + available to user as a convenience via IsMouse** API.
+    bool        MouseDown[5];                   // Mouse buttons: 0=left, 1=right, 2=middle + extras. ImGui itself mostly only uses left button (BeginPopupContext** are using right button). Others buttons allows us to track if the mouse is being used by your application + available to user as a convenience via IsMouse** API.
     float       MouseWheel;                     // Mouse wheel Vertical: 1 unit scrolls about 5 lines text.
     float       MouseWheelH;                    // Mouse wheel Horizontal. Most users don't have a mouse with an horizontal wheel, may not be filled by all back-ends.
     bool        MouseDrawCursor;                // Request ImGui to draw a mouse cursor for you (if you are on a platform without a mouse cursor).