diff --git a/examples/pen.c b/examples/pen.c
index a5f209650..105beefcc 100644
--- a/examples/pen.c
+++ b/examples/pen.c
@@ -74,9 +74,9 @@ static void key_callback(GLFWwindow* window, int key, int scancode, int action,
         glfwSetWindowShouldClose(window, GLFW_TRUE);
 }
 
-static void pen_callback(GLFWwindow* window, int pressure, int x, int y)
+static void pen_callback(GLFWwindow* window, double pressure, int x, int y)
 {
-	fprintf(stderr, "pressure -- %d --\n", pressure);
+	fprintf(stderr, "pressure -- %f --\n", pressure);
 	fprintf (stderr, "xPosition -- %d --\n", x);
 	fprintf(stderr, "yPosition -- %d --\n", y);
 }
diff --git a/include/GLFW/glfw3.h b/include/GLFW/glfw3.h
index 220a59213..005e58039 100644
--- a/include/GLFW/glfw3.h
+++ b/include/GLFW/glfw3.h
@@ -1279,21 +1279,23 @@ typedef void (* GLFWframebuffersizefun)(GLFWwindow*,int,int);
  */
 typedef void (* GLFWmousebuttonfun)(GLFWwindow*,int,int,int);
 
-/*! @brief The function signature for pen --pressure-- callbacks.
+/*! @brief The function signature for pen callbacks.
 *
-*  This is the function signature for pen --pressure-- callback functions.
+*  This is the function signature for pen callback functions.
 *
 *  @param[in] window The window that received the event.
 *  @param[in] pressure The [pen pressure](@ref pressure) that was pressed or
 *  released.
+*  @param[in] the x (horizontal point) coordinate of the point location of the pen.
+*  @param[in] the y (vertical point) coordinate of the point location of the pen.
 *  *
-*  @sa @ref input_pen_button
+*  @sa @ref input_pen_pressure
 *  @sa @ref glfwSetPenPressureCallback
 *
 *  @ingroup input
 */
 
-typedef void(*GLFWpenpressurefun)(GLFWwindow*, int, int, int);
+typedef void(*GLFWpenpressurefun)(GLFWwindow*, double, int, int);
 
 /*! @brief The function signature for cursor position callbacks.
  *
@@ -4144,17 +4146,11 @@ GLFWAPI GLFWcharmodsfun glfwSetCharModsCallback(GLFWwindow* window, GLFWcharmods
  *  @ingroup input
  */
 GLFWAPI GLFWmousebuttonfun glfwSetMouseButtonCallback(GLFWwindow* window, GLFWmousebuttonfun cbfun);
-/*! @brief Sets the pen --button-- callback.
-*
-*  This function sets the pen --button-- callback of the specified window, which
-*  is called when a pen --button-- is pressed or released.
-*
-*  When a window loses input focus, it will generate synthetic pen --button--
-*  release events for all pressed pen buttons.  You can tell these events
-*  from user-generated events by the fact that the synthetic ones are generated
-*  after the focus loss event has been processed, i.e. after the
-*  [window focus callback](@ref glfwSetWindowFocusCallback) has been called.
+/*! @brief Sets the pen callback.
 *
+*  This function sets the pen callback of the specified window, which
+*  is called when a pen is pressed or released.
+**
 *  @param[in] window The window whose callback to set.
 *  @param[in] cbfun The new callback, or `NULL` to remove the currently set
 *  callback.
@@ -4165,10 +4161,8 @@ GLFWAPI GLFWmousebuttonfun glfwSetMouseButtonCallback(GLFWwindow* window, GLFWmo
 *
 *  @thread_safety This function must only be called from the main thread.
 *
-*  @sa @ref input_pen_button
+*  @sa @ref input_pen_pressure
 *
-*  @since Added in version 1.0.
-*  @glfw3 Added window handle parameter and return value.
 *
 *  @ingroup input
 */
diff --git a/src/input.c b/src/input.c
index b8bda64e2..3138e8f0a 100644
--- a/src/input.c
+++ b/src/input.c
@@ -232,8 +232,7 @@ void _glfwInputMouseClick(_GLFWwindow* window, int button, int action, int mods)
         window->callbacks.mouseButton((GLFWwindow*) window, button, action, mods);
 }
 
-/*************************PEN**************************************************/
-void _glfwInputPenPressure(_GLFWwindow* window, int pressure, int x, int y)
+void _glfwInputPenPressure(_GLFWwindow* window, double pressure, int x, int y)
 {
 	window->penPressure = pressure;
 	window->penXposition = x;
@@ -242,7 +241,6 @@ void _glfwInputPenPressure(_GLFWwindow* window, int pressure, int x, int y)
 	if (window->callbacks.penPressure)
 		window->callbacks.penPressure((GLFWwindow*)window, pressure, x, y);
 }
-/***********************************PEN*************************************/
 
 void _glfwInputCursorPos(_GLFWwindow* window, double xpos, double ypos)
 {
@@ -733,7 +731,6 @@ GLFWAPI GLFWmousebuttonfun glfwSetMouseButtonCallback(GLFWwindow* handle,
     return cbfun;
 }
 
-/*********PEN************************************/
 GLFWAPI GLFWpenpressurefun glfwSetPenPressureCallback(GLFWwindow* handle,
 	GLFWpenpressurefun cbfun)
 {
@@ -744,7 +741,6 @@ GLFWAPI GLFWpenpressurefun glfwSetPenPressureCallback(GLFWwindow* handle,
 	_GLFW_SWAP_POINTERS(window->callbacks.penPressure, cbfun);
 	return cbfun;
 }
-/************************************************/
 
 GLFWAPI GLFWcursorposfun glfwSetCursorPosCallback(GLFWwindow* handle,
                                                   GLFWcursorposfun cbfun)
diff --git a/src/internal.h b/src/internal.h
index 1c567ea81..2b576ebbc 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -417,7 +417,7 @@ struct _GLFWwindow
 
     GLFWbool            stickyKeys;
     GLFWbool            stickyMouseButtons;
-	int					penPressure;
+	double				penPressure;
 	int                 penXposition;
 	int                 penYposition;
     int                 cursorMode;
@@ -820,14 +820,14 @@ void _glfwInputScroll(_GLFWwindow* window, double xoffset, double yoffset);
  */
 void _glfwInputMouseClick(_GLFWwindow* window, int button, int action, int mods);
 
-/*! @brief Notifies shared code of a pen button click event.
+/*! @brief Notifies shared code of a pen click event.
 *  @param[in] window The window that received the event.
-*  @param[in] button The button that was pressed or released.
-*  @param[in] action @ref GLFW_PRESS or @ref GLFW_RELEASE.
-*  @param[in] mods The modifiers pressed when the event was generated.
+*  @param[in] pressure when the pen was pressed.
+*  @param[in] x (horizontal point) coordinate of the point location of the pen.
+*  @param[in] y (vertical point) coordinate of the point location of the pen.
 *  @ingroup event
 */
-void _glfwInputPenPressure(_GLFWwindow* window, int pressure, int x, int y);
+void _glfwInputPenPressure(_GLFWwindow* window, double pressure, int x, int y);
 
 /*! @brief Notifies shared code of a cursor motion event.
  *  @param[in] window The window that received the event.
diff --git a/src/win32_window.c b/src/win32_window.c
index 360c96c65..987ab338e 100644
--- a/src/win32_window.c
+++ b/src/win32_window.c
@@ -597,8 +597,8 @@ static LRESULT CALLBACK windowProc(HWND hWnd, UINT uMsg,
 			else
 			{
 				// success, process penInfo
-				//We change the pen pressure which is given normalized to a range between 0 and 1024
-				//to a normalized value in [0..1]
+				// We change the pen pressure which is given normalized to a range between 0 and 1024
+				// to a normalized value in [0..1]
 				double pressure = (double)penInfo.pressure /(double) 1024;
 				int xPos = GET_X_LPARAM(lParam);
 				int yPos = GET_Y_LPARAM(lParam);