Avoid visual corruption if the game runs too fast.

If we run too fast while not in timedemo mode the game will
return immediately rather than rendering a frame.

If we go ahead and return to GLSurfaceView, it will swap the GL buffer
without having drawn anything into it, which will lead to garbage
being displayed.

The work-around is to detect that the game has decided to not render
anything, sleep for a ms and then try again.

Change-Id: Iba9d759547ddbc30534db963f5c47011038cc246

3 files changed, 17 insertions, 2 deletions

diff --git a/quake/src/WinQuake/host.cpp b/quake/src/WinQuake/host.cpp
index 670d7a0..f1af56a 100644
--- a/quake/src/WinQuake/host.cpp
+++ b/quake/src/WinQuake/host.cpp
@@ -42,6 +42,7 @@ double		host_time;
 double		realtime;				// without any filtering or bounding
 double		oldrealtime;			// last frame run
 int			host_framecount;
+qboolean    host_framethrottled; // Running too fast
 
 int			host_hunklevel;
 
@@ -644,7 +645,8 @@ void _Host_Frame (float time)
 	rand ();
 	
 // decide the simulation time
-	if (!Host_FilterTime (time))
+    host_framethrottled = !Host_FilterTime (time);
+	if (host_framethrottled)
 		return;			// don't run too fast, or packets will flood out
 		
 // get new key events
diff --git a/quake/src/WinQuake/quakedef.h b/quake/src/WinQuake/quakedef.h
index 6b42720..807b47d 100644
--- a/quake/src/WinQuake/quakedef.h
+++ b/quake/src/WinQuake/quakedef.h
@@ -308,6 +308,7 @@ extern	double		host_frametime;
 extern	byte		*host_basepal;
 extern	byte		*host_colormap;
 extern	int			host_framecount;	// incremented every frame, never reset
+extern  qboolean    host_framethrottled; // Running too fast
 extern	double		realtime;			// not bounded in any way, changed at
 										// start of every frame, never reset
 
diff --git a/quake/src/WinQuake/sys_android.cpp b/quake/src/WinQuake/sys_android.cpp
index 1537814..c66f01c 100644
--- a/quake/src/WinQuake/sys_android.cpp
+++ b/quake/src/WinQuake/sys_android.cpp
@@ -622,7 +622,7 @@ static void UpdateFrameTimes(float time)
   currentFrame++;
 }
 
-int AndroidStep(int width, int height)
+int AndroidStepImp(int width, int height)
 {
   // PMPBEGIN(("AndroidStep"));
   double time, newtime;
@@ -645,6 +645,18 @@ int AndroidStep(int width, int height)
   return key_dest == key_game;
 }
 
+int AndroidStep(int width, int height)
+{
+  for(;;) {
+    host_framethrottled = false;
+    int result = AndroidStepImp(width, height);
+    if (!host_framethrottled) {
+        return result;
+    }
+    usleep(1000);
+  }
+}
+
 extern void Host_Quit();
 void AndroidQuit() {
   soft_quit = true;