Added window position callback.

include/GL/glfw3.h

@@ -706,6 +706,16 @@ typedef void* GLFWwindow;
  */
 typedef void (* GLFWerrorfun)(int,const char*);
 
+/*! @brief The function signature for window position callbacks.
+ *  @param[in] window The window that the user moved.
+ *  @param[in] x The new x-coordinate, in pixels, of the upper-left corner of
+ *  the client area of the window.
+ *  @param[in] y The new y-coordinate, in pixels, of the upper-left corner of
+ *  the client area of the window.
+ *  @ingroup window
+ */
+typedef void (* GLFWwindowposfun)(GLFWwindow,int,int);
+
 /*! @brief The function signature for window resize callbacks.
  *  @param[in] window The window that the user resized.
  *  @param[in] width The new width, in pixels, of the window.
@@ -1274,6 +1284,14 @@ GLFWAPI void glfwSetWindowUserPointer(GLFWwindow window, void* pointer);
  */
 GLFWAPI void* glfwGetWindowUserPointer(GLFWwindow window);
 
+/*! @brief Sets the position callback for the specified window.
+ *  @param[in] window The window whose callback to set.
+ *  @param[in] cbfun The new callback, or @c NULL to remove the currently set
+ *  callback.
+ *  @ingroup window
+ */
+GLFWAPI void glfwSetWindowPosCallback(GLFWwindow window, GLFWwindowposfun cbfun);
+
 /*! @brief Sets the size callback for the specified window.
  *  @param[in] window The window whose callback to set.
  *  @param[in] cbfun The new callback, or @c NULL to remove the currently set

readme.html

@@ -274,7 +274,7 @@ version of GLFW.</p>
   <li>Added <code>glfwSetErrorCallback</code> function and <code>GLFWerrorfun</code> type for receiving more specific and/or nested errors</li>
   <li>Added <code>glfwSetWindowUserPointer</code> and <code>glfwGetWindowUserPointer</code> functions for per-window user pointers</li>
   <li>Added <code>glfwGetVersionString</code> function for determining which code paths were enabled at compile time</li>
-  <li>Added <code>glfwGetWindowPos</code> function for querying the position of the specified window</li>
+  <li>Added <code>glfwSetWindowPosCallback</code> function and <code>GLFWwindowposfun</code> type for reciving window position events</li>
   <li>Added <code>glfwSetWindowFocusCallback</code> function and <code>GLFWwindowfocusfun</code> type for receiving window focus events</li>
   <li>Added <code>glfwSetWindowIconifyCallback</code> function and <code>GLFWwindowiconifyfun</code> type for receiving window iconification events</li>
   <li>Added <code>glfwGetClipboardString</code> and <code>glfwSetClipboardString</code> functions for interacting with the system clipboard</li>
@@ -284,6 +284,7 @@ version of GLFW.</p>
   <li>Added <code>GLFW_OPENGL_REVISION</code> window parameter to make up for removal of <code>glfwGetGLVersion</code></li>
   <li>Added <code>GLFW_INCLUDE_GLCOREARB</code> macro for including <code>glcorearb.h</code> instead of <code>gl.h</code></li>
   <li>Added <code>GLFW_VISIBLE</code> window hint and parameter for controlling and polling window visibility</li>
+  <li>Added <code>GLFW_POSITION_X</code> and <code>GLFW_POSITION_Y</code> window hints and parameter for controlling and polling window position</li>
   <li>Added <code>windows</code> simple multi-window test program</li>
   <li>Added <code>sharing</code> simple OpenGL object sharing test program</li>
   <li>Added <code>modes</code> video mode enumeration and setting test program</li>

src/internal.h

@@ -199,6 +199,7 @@ struct _GLFWwindow
     int       glRobustness;
     PFNGLGETSTRINGIPROC GetStringi;
 
+    GLFWwindowposfun     windowPosCallback;
     GLFWwindowsizefun    windowSizeCallback;
     GLFWwindowclosefun   windowCloseCallback;
     GLFWwindowrefreshfun windowRefreshCallback;

src/window.c

@@ -119,8 +119,14 @@ void _glfwInputWindowFocus(_GLFWwindow* window, GLboolean focused)
 
 void _glfwInputWindowPos(_GLFWwindow* window, int x, int y)
 {
+    if (window->positionX == x && window->positionY == y)
+        return;
+
     window->positionX = x;
     window->positionY = y;
+
+    if (window->windowPosCallback)
+        window->windowPosCallback(window, x, y);
 }
 
 
@@ -764,6 +770,24 @@ GLFWAPI void* glfwGetWindowUserPointer(GLFWwindow handle)
 }
 
 
+//========================================================================
+// Set callback function for window position changes
+//========================================================================
+
+GLFWAPI void glfwSetWindowPosCallback(GLFWwindow handle, GLFWwindowposfun cbfun)
+{
+    _GLFWwindow* window = (_GLFWwindow*) handle;
+
+    if (!_glfwInitialized)
+    {
+        _glfwSetError(GLFW_NOT_INITIALIZED, NULL);
+        return;
+    }
+
+    window->windowPosCallback = cbfun;
+}
+
+
 //========================================================================
 // Set callback function for window size changes
 //========================================================================

tests/events.c

@@ -218,6 +218,15 @@ static const char* get_character_string(int character)
     return result;
 }
 
+static void window_pos_callback(GLFWwindow window, int x, int y)
+{
+    printf("%08x at %0.3f: Window position: %i %i\n",
+           counter++,
+           glfwGetTime(),
+           x,
+           y);
+}
+
 static void window_size_callback(GLFWwindow window, int width, int height)
 {
     printf("%08x at %0.3f: Window size: %i %i\n",
@@ -354,6 +363,7 @@ int main(void)
 
     printf("Window opened\n");
 
+    glfwSetWindowPosCallback(window, window_pos_callback);
     glfwSetWindowSizeCallback(window, window_size_callback);
     glfwSetWindowCloseCallback(window, window_close_callback);
     glfwSetWindowRefreshCallback(window, window_refresh_callback);