Android: drawing behaves nice enough. Fl::flush seems to bring the expected results, although optimization is required at some point.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12710 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

Android/HelloAndroid/app/src/main/cpp/HelloAndroid.cxx

@@ -146,6 +146,8 @@ int main(int argc, char **argv)
     btn = new Fl_Button(190, 200, 280, 35, "Hello, Android!");
     btn->color(FL_LIGHT2);
     win->show();
+  Fl::damage(FL_DAMAGE_ALL);
+  win->redraw();
 
 
     // loop waiting for stuff to do.
@@ -174,11 +176,7 @@ int main(int argc, char **argv)
                 return 0;
             }
         }
-      //Fl::flush();
-
-        if (engine.animating) {
-            engine_draw_frame();
-        }
+        Fl::flush();
     }
   return 0;
 }

src/drivers/Android/Fl_Android_Application.H

@@ -121,14 +121,12 @@ public:
   static void post_exec_cmd(int8_t cmd);
 
   static inline ANativeWindow *native_window() { return pNativeWindow; }
-  static inline ANativeWindow_Buffer &graphics_buffer() { return pNativeWindowBuffer; }
+  static inline ANativeWindow_Buffer &graphics_buffer() { return pApplicationWindowBuffer; }
   static int destroy_requested() { return pDestroyRequested; }
   static void set_on_app_cmd(void (*cmd)(int32_t cmd)) { pOnAppCmd = cmd; }
   static void set_on_input_event(int32_t (*cmd)(AInputEvent* event)) { pOnInputEvent = cmd; }
 
-  static bool lock_screen();
-  static void unlock_and_post_screen();
-  static bool screen_is_locked();
+  static void copy_screen();
 
 protected:
   static void free_saved_state();
@@ -138,6 +136,11 @@ protected:
   static void process_cmd(struct android_poll_source* source);
   static void* thread_entry(void* param);
 
+  static void allocate_screen();
+  static bool lock_screen();
+  static void unlock_and_post_screen();
+  static bool screen_is_locked();
+
   static ANativeActivity *pActivity;
   static AConfiguration *pConfig;
   static void *pSavedState;
@@ -146,6 +149,7 @@ protected:
   static AInputQueue *pInputQueue;
   static ANativeWindow *pNativeWindow;
   static ANativeWindow_Buffer pNativeWindowBuffer;
+  static ANativeWindow_Buffer pApplicationWindowBuffer;
   static int pActivityState;
   static int pDestroyRequested;
   static void (*pOnAppCmd)(int32_t cmd);

src/drivers/Android/Fl_Android_Application.cxx

@@ -70,6 +70,7 @@ ANativeWindow* Fl_Android_Application::pNativeWindow = 0;
 
 // Use this buffer for direct drawing access
 ANativeWindow_Buffer Fl_Android_Application::pNativeWindowBuffer = { 0 };
+ANativeWindow_Buffer Fl_Android_Application::pApplicationWindowBuffer = { 0 };
 
 // Current state of the app's activity.  May be either APP_CMD_START,
 // APP_CMD_RESUME, APP_CMD_PAUSE, or APP_CMD_STOP; see below.
@@ -366,6 +367,43 @@ void *Fl_Android_Application::thread_entry(void* param)
   return NULL;
 }
 
+/**
+ * Allocate memory for our internal screen buffer.
+ *
+ * FIXME: everything is currently hardcoded to an 600x800 resolution
+ * TODO: react to screen changes
+ */
+void Fl_Android_Application::allocate_screen() {
+  pApplicationWindowBuffer.bits = calloc(600*800, 2); // one uint16_t per pixel
+  pApplicationWindowBuffer.width = 600;
+  pApplicationWindowBuffer.height = 800;
+  pApplicationWindowBuffer.stride = 600;
+  pApplicationWindowBuffer.format = WINDOW_FORMAT_RGB_565;
+}
+
+
+#include <FL/fl_draw.H>
+
+void Fl_Android_Application::copy_screen()
+{
+  if (lock_screen()) {
+
+    static int i = 0;
+    fl_color( (i&1) ? FL_RED : FL_GREEN);
+    fl_rectf(i*10, 600+i*10, 50, 50);
+    i++;
+    if (i>10) i = 0;
+
+    // TODO: there are endless possibilities to optimize the following code
+    // We can identify previously written buffers and copy only those pixels
+    // that actually changed.
+    memcpy(pNativeWindowBuffer.bits,
+           pApplicationWindowBuffer.bits,
+           600*800*2);
+    unlock_and_post_screen();
+  }
+}
+
 /**
  * Take ownership of screen memory for gaining write access.
  *
@@ -386,25 +424,13 @@ bool Fl_Android_Application::lock_screen()
     return false;
   }
 
-  // 190, 200, 280, 35
-  ARect dirty = { .left=190, .top = 200, .right = 290, .bottom = 235 };
-  if (ANativeWindow_lock(pNativeWindow, &pNativeWindowBuffer, &dirty) < 0) {
+  if (ANativeWindow_lock(pNativeWindow, &pNativeWindowBuffer, 0L) < 0) {
     log_w("Unable to lock window buffer: Android won't lock.");
     return false;
   }
-  log_w("Dirty rect is %d %d %d %d", dirty.left, dirty.top, dirty.right, dirty.bottom);
-
-  ANativeWindow_Buffer buf;
-  if (ANativeWindow_lock(pNativeWindow, &buf, &dirty) < 0) {
-    log_w("Unable to lock 2nd window buffer: Android won't lock.");
-    return false;
-  }
-
   return true;
 }
 
-#include <FL/fl_draw.H>
-
 /**
  * Release screen memory ownership and give it back to the system.
  *
@@ -416,12 +442,6 @@ void Fl_Android_Application::unlock_and_post_screen()
   if (!screen_is_locked())
     return;
 
-  static int i = 0;
-  fl_color( (i&1) ? FL_RED : FL_GREEN);
-  fl_rectf(i*10, 700, 50, 50);
-  i++;
-  if (i>10) i = 0;
-
   ANativeWindow_unlockAndPost(pNativeWindow);
   pNativeWindowBuffer.bits = 0L; // avoid any misunderstandings...
 }
@@ -679,12 +699,14 @@ void Fl_Android_Activity::onInputQueueDestroyed(ANativeActivity* activity, AInpu
 void Fl_Android_Activity::create(ANativeActivity* activity, void* savedState,
                                  size_t savedStateSize)
 {
-  static char *FLTK = "FLTK";
+  static const char *FLTK = "FLTK";
   activity->instance = (void*)FLTK;
 
   set_activity(activity);
   set_callbacks();
 
+  allocate_screen(); // TODO: we may need to change this to when the actual screen is allocated
+
   pthread_mutex_init(&pMutex, NULL);
   pthread_cond_init(&pCond, NULL);
 

src/drivers/Android/Fl_Android_Screen_Driver.H

@@ -58,7 +58,7 @@ protected:
 #endif
 
 public:
-  Fl_Android_Screen_Driver() : Fl_Screen_Driver() { }
+  Fl_Android_Screen_Driver() : Fl_Screen_Driver(), pScreenContentChanged(false) { }
 
 #if 0
   Fl_WinAPI_Screen_Driver() : Fl_Screen_Driver() {
@@ -118,6 +118,7 @@ public:
   virtual float desktop_scale_factor();
 
 #endif
+  bool pScreenContentChanged;
 
 };
 

src/drivers/Android/Fl_Android_Screen_Driver.cxx

@@ -372,17 +372,16 @@ void Fl_WinAPI_Screen_Driver::beep(int type)
 #endif
 
 /**
- * On Android, get access to screen memory, then flush(), then
- * release screen memory and post it to the physicla screen.
- *
- * Don't do anything if the screen wasn't previously locked by
- * any Fl_Window_Driver. We would just needlessly repost the same screen.
+ * On Android, we currently write into a memory buffer and copy
+ * the content to the screen.
  */
 void Fl_Android_Screen_Driver::flush()
 {
-  if (Fl_Android_Application::screen_is_locked()) {
   Fl_Screen_Driver::flush();
-    Fl_Android_Application::unlock_and_post_screen();
+  // FIXME: do this only if anything actually changed on screen!
+  if (pScreenContentChanged) {
+    Fl_Android_Application::copy_screen();
+    pScreenContentChanged = false;
   }
 }
 

src/drivers/Android/Fl_Android_Window_Driver.cxx

@@ -77,7 +77,7 @@ void Fl_Android_Window_Driver::show()
 
 void Fl_Android_Window_Driver::make_current()
 {
-  Fl_Android_Application::lock_screen();
+  ((Fl_Android_Screen_Driver*)Fl::screen_driver())->pScreenContentChanged = true;
 }