Refresh the screen if pollEvent() is called without updateScreen() being called for a long time.

svn-id: r42139

1 files changed, 22 insertions, 4 deletions

diff --git a/backends/platform/dc/display.cpp b/backends/platform/dc/display.cpp
index ba8e1ba04f..d1e95c6a91 100644
--- a/backends/platform/dc/display.cpp
+++ b/backends/platform/dc/display.cpp
@@ -285,11 +285,8 @@ void OSystem_Dreamcast::setShakePos(int shake_pos)
   _current_shake_pos = shake_pos;
 }
 
-void OSystem_Dreamcast::updateScreen(void)
+void OSystem_Dreamcast::updateScreenTextures(void)
 {
-  struct polygon_list mypoly;
-  struct packed_colour_vertex_list myvertex;
-
   if (_screen_dirty) {
 
     _screen_buffer++;
@@ -328,6 +325,12 @@ void OSystem_Dreamcast::updateScreen(void)
 
     _overlay_dirty = false;
   }
+}
+
+void OSystem_Dreamcast::updateScreenPolygons(void)
+{
+  struct polygon_list mypoly;
+  struct packed_colour_vertex_list myvertex;
 
   // *((volatile unsigned int *)(void*)0xa05f8040) = 0x00ff00;
 
@@ -448,6 +451,21 @@ void OSystem_Dreamcast::updateScreen(void)
   ta_commit_frame();
 
   // *((volatile unsigned int *)(void*)0xa05f8040) = 0x0;
+
+  _last_screen_refresh = Timer();
+}
+
+void OSystem_Dreamcast::updateScreen(void)
+{
+  updateScreenTextures();
+  updateScreenPolygons();
+}
+
+void OSystem_Dreamcast::maybeRefreshScreen(void)
+{
+  unsigned int t = Timer();
+  if((int)(t-_last_screen_refresh) > USEC_TO_TIMER(30000))
+    updateScreenPolygons();
 }
 
 void OSystem_Dreamcast::drawMouse(int xdraw, int ydraw, int w, int h,