commit 7e969b3ca72c7522c2e5ce78cee82997ac1d32af
author Jason Sams <rjsams@android.com> Wed Oct 07 20:20:30 2009 -0700
committer Android Git Automerger <android-git-automerger@android.com> Wed Oct 07 20:20:30 2009 -0700
tree 5d336b480d0cdab3bdd161c28ecc81820a1065b1
parent e3264d7234f0568d6619c8955f5480963a2019ff
parent 267d4fa58ba38160df9fe33d4ea126fe7e5d6230

am 267d4fa5: Fix physics bug when the script would go to sleep.  The large DT caused the next animation to error.  Stop rendering after one frame past last movement.

Merge commit '267d4fa58ba38160df9fe33d4ea126fe7e5d6230' into eclair-mr2

* commit '267d4fa58ba38160df9fe33d4ea126fe7e5d6230':
  Fix physics bug when the script would go to sleep.  The large DT caused the next animation to error.  Stop rendering after one frame past last movement.

res/raw/rollo.c

diff --git a/res/raw/rollo.c b/res/raw/rollo.c
index bae786d..87fdd22 100644
--- a/res/raw/rollo.c
+++ b/res/raw/rollo.c
@@ -27,6 +27,16 @@
 float g_OldPosVelocity;
 float g_OldZoom;
 
+int g_DrawLastFrame;
+int lastFrame(int draw) {
+    // We draw one extra frame to work around the last frame post bug.
+    // We also need to track if we drew the last frame to deal with large DT
+    // in the physics.
+    int ret = g_DrawLastFrame | draw;
+    g_DrawLastFrame = draw;
+    return ret;  // should return draw instead.
+}
+
 void updateReadback() {
     if ((g_OldPosPage != g_PosPage) ||
         (g_OldPosVelocity != g_PosVelocity) ||
@@ -309,6 +319,16 @@
     g_DT = (newTime - g_LastTime) / 1000.f;
     g_LastTime = newTime;
 
+    if (!g_DrawLastFrame) {
+        // If we stopped rendering we cannot use DT.
+        // assume 30fps in this case.
+        g_DT = 0.033f;
+    }
+    if (g_DT > 0.2f) {
+        // physics may break if DT is large.
+        g_DT = 0.2f;
+    }
+
     //debugF("zoom", g_Zoom);
     if (g_Zoom != state->zoomTarget) {
         float dz = (state->zoomTarget - g_Zoom) * g_DT * 5;
@@ -334,7 +354,7 @@
         if (!g_LastTouchDown) {
             g_PosPage = 0;
         }
-        return 1;//0;
+        return lastFrame(0);
     } else if (g_Zoom < 0.85f) {
         pfClearColor(0.0f, 0.0f, 0.0f, g_Zoom);
     } else {
@@ -356,7 +376,7 @@
     color(1.0f, 1.0f, 1.0f, 0.99f);
 
     if (iconCount <= 0) {
-        return 1;
+        return lastFrame(0);
     }
     int lastIcon = iconCount-1;
 
@@ -404,6 +424,6 @@
 
     // Bug workaround where the last frame is not always displayed
     // So we keep rendering until the bug is fixed.
-    return 1;//(g_PosVelocity != 0) || fracf(g_PosPage) || (g_Zoom != state->zoomTarget);
+    return lastFrame((g_PosVelocity != 0) || fracf(g_PosPage) || (g_Zoom != state->zoomTarget));
 }