From: Joe Wreschnig <joe.wreschnig@gmail.com>
Date: Thu, 18 Sep 2014 15:04:00 +0000 (+0200)
Subject: Derive rotor angles from bodies.
X-Git-Url: https://git.yukkurigames.com/?a=commitdiff_plain;h=ca536dd9d6bf0f56875175560c586c79a10eeade;p=featherfall2.git

Derive rotor angles from bodies.
---

diff --git a/src/main.js b/src/main.js
index ecff045..1846c3e 100644
--- a/src/main.js
+++ b/src/main.js
@@ -65,6 +65,7 @@ var BodyC = yT(yuu.C, {
     },
 
     position: { alias: 'body.position' },
+    angle: { alias: 'body.angle' },
     linearVelocity: { alias: 'body.linearVelocity' },
     ApplyForce: { proxy: 'body.ApplyForce' },
 
@@ -89,8 +90,6 @@ var PlayerController = yT(yuu.C, {
             this.drightLeft = this.drightRight = 0;
         this.up = 0;
         this.free = 0;
-        this.leftPivot = 0;
-        this.rightPivot = 0;
         this.commands = {
             dleftLeft: yuu.propcmd(this, 'dleftLeft'),
             dleftRight: yuu.propcmd(this, 'dleftRight'),
@@ -102,43 +101,43 @@ var PlayerController = yT(yuu.C, {
     },
 
     _updatePivots: function () {
-        var PIVOT_SPEED = 0.05;
-        var leftSpeed = (this.dleftRight - this.dleftLeft) * PIVOT_SPEED;
-        var rightSpeed = (this.drightLeft - this.drightRight) * PIVOT_SPEED;
-        this.leftPivot = yf.clamp(this.leftPivot + leftSpeed, 0, 1);
-        this.rightPivot = yf.clamp(this.rightPivot + rightSpeed, 0, 1);
+        var PIVOT_SPEED = 2;
+        this.leftJoint.motorSpeed =
+            (this.dleftRight - this.dleftLeft) * PIVOT_SPEED;
+        this.rightJoint.motorSpeed =
+            (this.drightRight - this.drightLeft) * PIVOT_SPEED;
     },
 
     _updateTransforms: function () {
-        var gain = 1.0;
-        var leftTarget = this.leftPivot * Math.PI / 2;
-        var rightTarget = -this.rightPivot * Math.PI / 2;
-        var leftError = this.leftJoint.jointAngle - leftTarget;
-        var rightError = this.rightJoint.jointAngle - rightTarget;
-        this.leftJoint.motorSpeed = -gain * leftError;
-        this.rightJoint.motorSpeed = -gain * rightError;
     },
 
     tick: function () {
         this._updatePivots();
-        var THRUST = 3.5;
-        var DRAG_FREE = 0.01;
+        var THRUST = 5;
+/*        var DRAG_FREE = 0.01;
         var DRAG_OPEN = 0.5;
         var DRAG_LOCK = 1;
-        var CORRECTION = 1;
+        var CORRECTION = 1;*/
 
-        var leftAngle = (1 - this.leftPivot) * Math.PI / 2;
-        var rightAngle = (1 - this.rightPivot) * Math.PI / 2;
+        var leftAngle = this.leftJoint.GetJointAngle();
+        var rightAngle = this.rightJoint.GetJointAngle();
+        var thrust = +!this.free * +this.up * THRUST;
+        var leftThrust = new b2Vec2(
+            Math.sin(leftAngle) * thrust, Math.cos(leftAngle) * thrust);
+        var rightThrust = new b2Vec2(
+            Math.sin(rightAngle) * thrust, Math.cos(rightAngle) * thrust);
+        this.body.body.ApplyForceToCenter(leftThrust);
+        this.body.body.ApplyForceToCenter(rightThrust);
 
         var cleft = Math.cos(leftAngle);
         var cright = Math.cos(rightAngle);
         var sleft = Math.sin(leftAngle);
         var sright = Math.sin(rightAngle); 
 
-        var thrust = +!this.free * +this.up * THRUST;
         var ax = thrust * (cleft - cright); 
         var ay = thrust * (sright + sleft);
 
+        /*
         var v = this.body.linearVelocity;
         var drag = this.up ? DRAG_OPEN : this.free ? DRAG_FREE : DRAG_LOCK;
         ax += drag * Math.max(cleft, cright) * v.x * v.x * -Math.sign(v.x);
@@ -146,6 +145,7 @@ var PlayerController = yT(yuu.C, {
 
         if (!this.up || this.free)
             ax += CORRECTION * (cleft - cright) * v.y * v.y * Math.sign(v.y);
+        */
 
         this.body.ApplyForce(new b2Vec2(ax, ay), this.body.position);
 
@@ -155,23 +155,26 @@ var PlayerController = yT(yuu.C, {
     TAPS: ['tick'],
 });
 
-function bodyFromAABB (world, position, aabb, density) {
-    var bd = new Box2D.b2BodyDef();
+function bodyFromAABB (world, position, aabb, density, center) {
+    var dfn = new Box2D.b2BodyDef();
     var shape = new Box2D.b2PolygonShape();
-    shape.SetAsBox(aabb.hw, aabb.hh);
-    if (density)
-        bd.type = Box2D.DYNAMIC_BODY;
-    bd.position = new b2Vec2(position[0], position[1]);
-    var body = world.CreateBody(bd);
-    body.CreateFixture(shape, density || 0);
+    if (center)
+        shape.SetAsBox(aabb.hw, aabb.hh, new b2Vec2(center), 0);
+    else
+        shape.SetAsBox(aabb.hw, aabb.hh);
+    if (density !== undefined)
+        dfn.type = Box2D.DYNAMIC_BODY;
+    dfn.position = new b2Vec2(position[0], position[1]);
+    var body = world.CreateBody(dfn);
+    body.CreateFixture(shape, density || 0.0001);
     return body;
 }
 
 function bodyFromLine (world, p0, p1) {
-    var bd = new Box2D.b2BodyDef();
+    var dfn = new Box2D.b2BodyDef();
     var shape = new Box2D.b2EdgeShape();
     shape.Set(new b2Vec2(p0), new b2Vec2(p1));
-    var body = world.CreateBody(bd);
+    var body = world.CreateBody(dfn);
     body.CreateFixture(shape, 0);
     return body;
 }
@@ -179,9 +182,10 @@ function bodyFromLine (world, p0, p1) {
 function pinJoint (world, bodyA, bodyB, anchor) {
     var dfn = new Box2D.b2RevoluteJointDef();
     dfn.Initialize(bodyA, bodyB, new b2Vec2(anchor));
-    dfn.maxMotorTorque = 10.0;
-    dfn.motorSpeed = 0.0;
+    dfn.maxMotorTorque = 100.0;
+    dfn.motorSpeed = 0.1;
     dfn.enableMotor = true;
+    dfn.enableLimit = true;
     return Box2D.castObject(world.CreateJoint(dfn), Box2D.b2RevoluteJoint);
 }
 
@@ -203,20 +207,25 @@ var GameScene = yT(yuu.Scene, {
                 .setSize([0.89, 1.0])
         );
 
-        var leftWing = new yuu.E(left = new BodyC(
-            bodyFromAABB(world, [-0.50, 5.15], new yuu.AABB(0.45, 0.22), 1.0)),
+        var leftWing = new yuu.E(
+            left = new BodyC(bodyFromAABB(
+                     world, [-0.275, 5.15], new yuu.AABB(0.45, 0.22), 0,
+                [-0.45/2, 0.0])),
             new yuu.QuadC('@left')
+                .setAnchorAtPosition("right")
                 .setZ(-1)
                 .setSize([0.45, 0.22]));
-        var leftJoint = pinJoint(world, left.body, body.body, [-0.1, 5.15]);
+        var leftJoint = pinJoint(world, left.body, body.body, [0.1, 5.15]);
         var rightWing = new yuu.E(right = new BodyC(
-            bodyFromAABB(world, [0.50, 5.15], new yuu.AABB(0.45, 0.22), 1.0)),
+            bodyFromAABB(world, [0.50, 5.15], new yuu.AABB(0.45, 0.22), 0)),
             new yuu.QuadC('@right')
                 .setZ(-1)
                 .setSize([0.45, 0.22]));
         var rightJoint = pinJoint(world, right.body, body.body, [0.1, 5.15]);
         this.player.addChildren(leftWing, rightWing);
         this.entity0.addChild(this.player);
+        leftJoint.SetLimits(0, Math.PI / 2);
+        rightJoint.SetLimits(-Math.PI / 2, 0);
 
         var ground = new yuu.E(
             new BodyC(bodyFromLine(world, [-100, 0], [100, 0])),
@@ -228,7 +237,7 @@ var GameScene = yT(yuu.Scene, {
 
         this.player.attach(
             this.controller = new PlayerController(body, left, right,
-                                                  leftJoint, rightJoint));
+                                                   leftJoint, rightJoint));
         Object.assign(this.commands, this.controller.commands);
 
         this.entity0.attach(new yuu.Ticker(function () {