From 274ab21d3eda3cf6147c7b4fa9fba41efb267b53 Mon Sep 17 00:00:00 2001
From: polygonboutique <sergej.schefer@web.de>
Date: Fri, 4 Nov 2016 15:50:33 +0100
Subject: [PATCH] follow & look at components

---
 src/game-lib-component-camera-follow.js | 18 ----------
 src/game-lib-component-follow.js        | 26 ++++++++++++++
 src/game-lib-component-look-at.js       | 46 +++++++++++++++++++++++++
 3 files changed, 72 insertions(+), 18 deletions(-)
 delete mode 100644 src/game-lib-component-camera-follow.js
 create mode 100644 src/game-lib-component-follow.js
 create mode 100644 src/game-lib-component-look-at.js

diff --git a/src/game-lib-component-camera-follow.js b/src/game-lib-component-camera-follow.js
deleted file mode 100644
index 15cd2d2..0000000
--- a/src/game-lib-component-camera-follow.js
+++ /dev/null
@@ -1,18 +0,0 @@
-GameLib.D3.ComponentCameraFollow = function(
-    componentId,
-    targetEntity
-) {
-    this.componentId = componentId || GameLib.D3.Tools.RandomId();
-    this.parentEntity = null;
-
-    // Todo: this should be executed somewhere in game-lib-z, so that we don't execute it on every construction of an object.
-    GameLib.D3.Utils.Extend(GameLib.D3.ComponentCameraFollow, GameLib.D3.ComponentInterface);
-};
-
-///////////////////////// Methods to override //////////////////////////
-GameLib.D3.ComponentCameraFollow.prototype.onUpdate = function(
-    deltaTime,
-    parentEntity
-) {
-    //
-};
\ No newline at end of file
diff --git a/src/game-lib-component-follow.js b/src/game-lib-component-follow.js
new file mode 100644
index 0000000..9aeec20
--- /dev/null
+++ b/src/game-lib-component-follow.js
@@ -0,0 +1,26 @@
+GameLib.D3.ComponentFollow = function(
+    componentId,
+    targetEntity
+) {
+    this.componentId = componentId || GameLib.D3.Tools.RandomId();
+    this.parentEntity = null;
+
+    // Todo: this should be executed somewhere in game-lib-z, so that we don't execute it on every construction of an object.
+    GameLib.D3.Utils.Extend(GameLib.D3.ComponentFollow, GameLib.D3.ComponentInterface);
+
+    //
+    this.targetEntity = targetEntity;
+    this.moveSpeed = 2.5;
+};
+
+///////////////////////// Methods to override //////////////////////////
+GameLib.D3.ComponentFollow.prototype.onUpdate = function(
+    deltaTime,
+    parentEntity
+) {
+    if(this.targetEntity) {
+        var target = new THREE.Vector3().copy(this.targetEntity.position);
+
+        parentEntity.position = parentEntity.position.lerp(target, this.moveSpeed * deltaTime);
+    }
+};
\ No newline at end of file
diff --git a/src/game-lib-component-look-at.js b/src/game-lib-component-look-at.js
new file mode 100644
index 0000000..6d1a4e2
--- /dev/null
+++ b/src/game-lib-component-look-at.js
@@ -0,0 +1,46 @@
+GameLib.D3.ComponentLookAt = function(
+    componentId,
+    targetEntity
+) {
+    this.componentId = componentId || GameLib.D3.Tools.RandomId();
+    this.parentEntity = null;
+
+    // Todo: this should be executed somewhere in game-lib-z, so that we don't execute it on every construction of an object.
+    GameLib.D3.Utils.Extend(GameLib.D3.ComponentLookAt, GameLib.D3.ComponentInterface);
+
+    //
+    this.targetEntity = targetEntity;
+};
+
+///////////////////////// Methods to override //////////////////////////
+GameLib.D3.ComponentLookAt.prototype.onUpdate = function(
+    deltaTime,
+    parentEntity
+) {
+    if(this.targetEntity) {
+        var target = this.targetEntity.position;
+        var lookAtMatrix = new THREE.Matrix4().lookAt(
+            new THREE.Vector3(
+                parentEntity.position.x,
+                parentEntity.position.y,
+                parentEntity.position.z
+            ),
+            new THREE.Vector3(
+                target.x,
+                target.y,
+                target.z
+            ),
+            new THREE.Vector3(
+                0,
+                1,
+                0
+            )
+        );
+
+        var quaternion = new THREE.Quaternion().setFromRotationMatrix(lookAtMatrix);
+        this.parentEntity.quaternion.x = quaternion.x;
+        this.parentEntity.quaternion.y = quaternion.y;
+        this.parentEntity.quaternion.z = quaternion.z;
+        this.parentEntity.quaternion.w = quaternion.w;
+    }
+};
\ No newline at end of file