Added accelerometer 'joystick'

src/joystick/android/SDL_sysjoystick.c

+/*
+    SDL - Simple DirectMedia Layer
+    Copyright (C) 1997-2010 Sam Lantinga
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+    Sam Lantinga
+    slouken@libsdl.org
+*/
+
+#include "SDL_config.h"
+
+#ifdef SDL_JOYSTICK_ANDROID
+
+/* This is the system specific header for the SDL joystick API */
+#include <stdio.h>              /* For the definition of NULL */
+
+#include "SDL_error.h"
+#include "SDL_events.h"
+#include "SDL_joystick.h"
+#include "../SDL_sysjoystick.h"
+#include "../SDL_joystick_c.h"
+
+extern float fLastAccelerometer[3];
+
+const char *accelerometerName = "Android accelerometer";
+
+/* Function to scan the system for joysticks.
+ * This function should set SDL_numjoysticks to the number of available
+ * joysticks.  Joystick 0 should be the system default joystick.
+ * It should return 0, or -1 on an unrecoverable fatal error.
+ */
+int
+SDL_SYS_JoystickInit(void)
+{
+    SDL_numjoysticks = 1;
+    
+return (1);
+}
+
+/* Function to get the device-dependent name of a joystick */
+const char *
+SDL_SYS_JoystickName(int index)
+{
+    if (!index)
+        return accelerometerName;
+    SDL_SetError("No joystick available with that index");
+    return (NULL);
+}
+
+/* Function to open a joystick for use.
+   The joystick to open is specified by the index field of the joystick.
+   This should fill the nbuttons and naxes fields of the joystick structure.
+   It returns 0, or -1 if there is an error.
+ */
+int
+SDL_SYS_JoystickOpen(SDL_Joystick * joystick)
+{
+    joystick->nbuttons = 0;
+    joystick->nhats = 0;
+    joystick->nballs = 0;
+    joystick->naxes = 3;
+    joystick->name = accelerometerName;
+    return 0;
+}
+
+
+/* Function to update the state of a joystick - called as a device poll.
+ * This function shouldn't update the joystick structure directly,
+ * but instead should call SDL_PrivateJoystick*() to deliver events
+ * and update joystick device state.
+ */
+    void
+SDL_SYS_JoystickUpdate(SDL_Joystick * joystick)
+{
+    int i=0; 
+    for(i=0;i<3;i++){
+        SDL_PrivateJoystickAxis(joystick, i, fLastAccelerometer[i]);
+    }
+}
+
+/* Function to close a joystick after use */
+void
+SDL_SYS_JoystickClose(SDL_Joystick * joystick)
+{
+}
+
+/* Function to perform any system-specific joystick related cleanup */
+void
+SDL_SYS_JoystickQuit(void)
+{
+}
+
+#endif /* SDL_JOYSTICK_NDS */