Change the extra culling to do only a quarter of the scene every 200

frames rather than the whole thing, to avoid tiny stutters.

diff --git a/src/Main/main.cxx b/src/Main/main.cxx
index fce651f522aab936e211b26f7db827aec919e21e..2b0dde6710b71f0a2e09dd8eb94196f606c3fb65 100644 (file)
--- a/src/Main/main.cxx
+++ b/src/Main/main.cxx
@@ -647,20 +647,34 @@ void fgRenderFrame() {
         ssgSetNearFar( scene_nearplane, scene_farplane );
        ssgCullAndDraw( globals->get_scenery()->get_scene_graph() );
 
-       // This is a bit kludgy.  Every 200 frames, do an extra traversal
-       // of the scene graph without drawing anything and with frustum
-       // culling disabled.  This ensures that out-of-range random
-       // objects that are not in the current view frustum will still be
-       // freed properly.
+       // This is a bit kludgy.  Every 200 frames, do an extra
+       // traversal of the scene graph without drawing anything and
+       // the frustum set to a different 25% of the full range of
+       // view.  This ensures that out-of-range random objects that
+       // are not in the current view frustum will still be freed
+       // properly.
        static int counter = 0;
-       if (++counter == 200) {
-                               // We disable frustrum testing, so 
-                               // the default is fine.
+       counter++;
+       if (counter % 200 == 0) {
          sgFrustum f;
+         switch (counter) {
+         case 200:
+           f.setFrustum(SG_180, SG_ZERO, SG_90, SG_ZERO, 0, 500000000);
+           break;
+         case 400:
+           f.setFrustum(SG_ZERO, SG_180, SG_90, SG_ZERO, 0, 500000000);
+           break;
+         case 600:
+           f.setFrustum(SG_180, SG_ZERO, SG_ZERO, SG_90, 0, 500000000);
+           break;
+         case 800:
+           f.setFrustum(SG_ZERO, SG_180, SG_ZERO, SG_90, 0, 500000000);
+           counter = 0;
+           break;
+         }
          sgMat4 m;
          ssgGetModelviewMatrix(m);
-         globals->get_scenery()->get_scene_graph()->cull(&f, m, false);
-         counter = 0;
+         globals->get_scenery()->get_scene_graph()->cull(&f, m, true);
        }
 
        // change state for lighting here