From c1c521edf4fbb7048a4fba601d13a765e073e402 Mon Sep 17 00:00:00 2001
From: Jason Sams <rjsams@android.com>
Date: Mon, 19 Oct 2009 14:45:45 -0700
Subject: Add support for MoveTo.

---
 res/raw/rollo3.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

(limited to 'res/raw')

diff --git a/res/raw/rollo3.c b/res/raw/rollo3.c
index bb0237376..253709a44 100644
--- a/res/raw/rollo3.c
+++ b/res/raw/rollo3.c
@@ -22,6 +22,10 @@ float g_Zoom;
 float g_OldPosPage;
 float g_OldPosVelocity;
 float g_OldZoom;
+float g_MoveToTotalTime;
+float g_MoveToTime;
+float g_MoveToOldPos;
+
 
 // Drawing constants, should be parameters ======
 #define VIEW_ANGLE 1.28700222f
@@ -79,6 +83,9 @@ void init() {
     g_LastPositionX = 0;
     g_Zoom = 0;
     g_SpecialHWWar = 1;
+    g_MoveToTime = 0;
+    g_MoveToOldPos = 0;
+    g_MoveToTotalTime = 0.5f;
 }
 
 void resetHWWar() {
@@ -97,9 +104,16 @@ void move() {
     }
     g_LastTouchDown = state->newTouchDown;
     g_LastPositionX = state->newPositionX;
+    g_MoveToTime = 0;
     //debugF("Move P", g_PosPage);
 }
 
+void moveTo() {
+    g_MoveToTime = g_MoveToTotalTime;
+    g_PosVelocity = 0;
+    g_MoveToOldPos = g_PosPage;
+}
+
 void fling() {
     g_LastTouchDown = 0;
     g_PosVelocity = -state->flingVelocity * 4;
@@ -145,6 +159,25 @@ void updatePos() {
                         tablePosFrac) * g_DT;
     float friction = 4.f * g_DT;
 
+    if (g_MoveToTime) {
+        float a = 2.f * (state->targetPos - g_MoveToOldPos) /
+                  (g_MoveToTotalTime * g_MoveToTotalTime);
+        if (g_MoveToTime > (g_MoveToTotalTime * 0.5f)) {
+            // slowing
+            g_PosPage = state->targetPos - 0.5f * a * (g_MoveToTime * g_MoveToTime);
+        } else {
+            // accelerating.
+            float t = g_MoveToTotalTime - g_MoveToTime;
+            g_PosPage = g_MoveToOldPos + 0.5f * a * (t * t);
+        }
+        g_MoveToTime -= g_DT;
+        if (g_MoveToTime <= 0) {
+            g_MoveToTime = 0;
+            g_PosPage = state->targetPos;
+        }
+        return;
+    }
+
     if (g_PosPage < -0.5f) {
         accel = g_AttractionTable[0] * g_DT;
         outOfRange = 1;
-- 
cgit v1.2.3