From 4b9b3ac75620e7e6bb08c1118eb96c769268b5db Mon Sep 17 00:00:00 2001
From: polygonboutique <sergej.schefer@web.de>
Date: Fri, 30 Sep 2016 15:57:36 +0200
Subject: [PATCH] GenerateTriangleCollisionMesh, GetIndexedVertices,
 GenerateWireframeViewMesh

---
 game-lib.js | 155 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 155 insertions(+)

diff --git a/game-lib.js b/game-lib.js
index 9b073a0..c62cd4f 100644
--- a/game-lib.js
+++ b/game-lib.js
@@ -2608,6 +2608,161 @@ GameLib.D3.prototype.loadScene = function(blenderScene, onLoaded, computeNormals
     });
 };
 
+// ---------------
+// Physics
+// ---------------
+
+GameLib.D3.Physics.World.GetIndexedVertices = function(
+   triangleMeshShape
+) {
+
+    if(this.engine.engineType == GameLib.D3.Physics.Engine.TYPE_CANNON) {
+
+        return {
+            vertices : triangleMeshShape.vertices,
+            indices : triangleMeshShape.indices
+        };
+
+    } else {
+        // todo: implement this for other physics engines.
+        return null;
+    }
+
+};
+
+GameLib.D3.Physics.World.GenerateWireframeViewMesh = function(
+    triangleMeshShape,
+    normalLength,
+    scale,
+    opacity,
+    wireframeColor
+) {
+    var geometryTHREE = new THREE.Geometry();
+    var wireframeTHREEMesh = new THREE.Mesh
+    (
+        geometryTHREE,
+        new THREE.MeshBasicMaterial({
+            color: wireframeColor ? wireframeColor : 0xfefefe,
+            wireframe: true,
+            opacity: opacity ? opacity : 0.5
+        })
+    );
+
+    var data = this.GetIndexedVertices(triangleMeshShape);
+
+    for(var i = 0, l = data.vertices.length / 3; i < l; i++) {
+        geometryTHREE.vertices.push(new THREE.Vector3(data.vertices[i * 3], data.vertices[i * 3 + 1], data.vertices[i * 3 + 2]));
+    }
+
+    for(var i = 0, l = data.indices.length / 3; i < l; i++) {
+        var i0 = data.indices[i * 3];
+        var i1 = data.indices[i * 3 + 1];
+        var i2 = data.indices[i * 3 + 2];
+
+        geometryTHREE.faces.push(new THREE.Face3(i0, i1, i2));
+
+        // Create debug view for normals
+
+        // Center point on the mesh itself
+        var centroid = new THREE.Vector3()
+            .add(geometryTHREE.vertices[i0])
+            .add(geometryTHREE.vertices[i1])
+            .add(geometryTHREE.vertices[i2])
+            .divideScalar(3);
+
+        var normal = null;
+        if(this.engine.engineType == GameLib.D3.Physics.Engine.TYPE_CANNON) {
+            var normal = new CANNON.Vec3();
+            triangleMeshShape.getNormal(i, normal);
+        } else {
+            // todo: calculate the normal for v0, v1 & v2 here.
+        }
+
+        var arrow = new THREE.ArrowHelper(new THREE.Vector3(normal.x, normal.y, normal.z), centroid, normalLength, new THREE.Color(normal.x, normal.y, normal.z));
+        wireframeTHREEMesh.add( arrow );
+    }
+
+    wireframeTHREEMesh.scale.x = scale.x;
+    wireframeTHREEMesh.scale.y = scale.y;
+    wireframeTHREEMesh.scale.z = scale.z;
+
+    return wireframeTHREEMesh;
+};
+
+GameLib.D3.Physics.World.GenerateTriangleCollisionMesh = function(
+    threeMesh,
+    mass,                       // default = 0
+    friction,                   // default = 10
+    createCollisionSubMeshes,   // boolean. default = false
+    facesPerSubsection,        // int. default = 0
+    subsectionsToMerge         // int. default = 0
+) {
+    var processedFaces = 0;
+    var facesPerSubSection = facesPerSubsection || 0;
+    var subMeshesToMerge = subsectionsToMerge || 0;
+    var totalAmtFaces = threeMesh.geometry.faces.length;
+    var facesToProcess = createCollisionSubMeshes ? (subMeshesToMerge * facesPerSubSection) : totalAmtFaces;
+
+    var pairs = []; // output
+
+    var vertices = [];
+    var indicies = [];
+
+    for(var i = 0; i <= totalAmtFaces; i++) {
+        if(processedFaces == facesToProcess || i == totalAmtFaces) {
+
+            var body = null;
+
+            if(this.engine.engineType == GameLib.D3.Physics.Engine.TYPE_CANNON) {
+
+                var meshShape = new CANNON.Trimesh(vertices, indicies);
+                meshShape.setScale(new CANNON.Vec3(threeMesh.scale.x, threeMesh.scale.y, threeMesh.scale.z));
+                meshShape.updateAABB();
+                meshShape.updateNormals();
+                meshShape.updateEdges();
+                meshShape.updateBoundingSphereRadius();
+                meshShape.updateTree();
+
+                body = new CANNON.Body({ mass: mass ? mass : 0, friction: friction ? friction : 10 });
+                body.addShape(meshShape);
+
+            } else if (this.engine.engineType == GameLib.D3.Physics.Engine.TYPE_AMMO) {
+
+            } else if (this.engine.engineType == GameLib.D3.Physics.Engine.TYPE_GOBLIN) {
+
+            }
+
+            pairs.push({
+                threeObject : createCollisionSubMeshes ? null : threeMesh,
+                physicsObject : body
+            });
+
+            vertices = [];
+            indicies = [];
+            processedFaces = 0;
+
+            if(i == totalAmtFaces) {
+                return pairs;
+            }
+        }
+
+        var face = threeMesh.geometry.faces[i];
+        indicies.push(indicies.length);
+        indicies.push(indicies.length);
+        indicies.push(indicies.length);
+
+        var v0 = threeMesh.geometry.vertices[face.a];
+        var v1 = threeMesh.geometry.vertices[face.b];
+        var v2 = threeMesh.geometry.vertices[face.c];
+
+        vertices.push(v0.x, v0.y, v0.z);
+        vertices.push(v1.x, v1.y, v1.z);
+        vertices.push(v2.x, v2.y, v2.z);
+
+        processedFaces++;
+    }
+};
+
 if (typeof module != 'undefined') {
     module.exports = GameLib.D3;
 }
\ No newline at end of file