SPS particle parenting feature

src/Particles/babylon.solidParticle.ts

@@ -94,6 +94,15 @@ module BABYLON {
          * Last computed particle rotation matrix
          */
         public _rotationMatrix: number[] = [1.0, 0.0, 0.0, 0.0, 1.0, 0.0, 0.0, 0.0, 1.0];
+        /**
+         * Parent particle Id, if any.
+         * Default null.
+         */
+        public parentId: Nullable<number> = null;
+        /**
+         * Internal global position in the SPS.
+         */
+        public _globalPosition: Vector3 = Vector3.Zero();
 
         /**
          * Creates a Solid Particle object.

src/Particles/babylon.solidParticleSystem.ts

@@ -134,6 +134,9 @@
                 };
             private _needs32Bits: boolean = false;
             private _pivotBackTranslation: Vector3 = Vector3.Zero();
+            private _scaledPivot: Vector3 = Vector3.Zero();
+            private _particleHasParent: boolean = false;
+            private _parent: SolidParticle;
 
             /**
              * Creates a SPS (Solid Particle System) object.
@@ -399,12 +402,16 @@
                     this._quaternionRotationYPR();
                 }
                 this._quaternionToRotationMatrix();
+
+                this._scaledPivot.x = this._copy.pivot.x * this._copy.scaling.x;
+                this._scaledPivot.y = this._copy.pivot.y * this._copy.scaling.y;
+                this._scaledPivot.z = this._copy.pivot.z * this._copy.scaling.z;
                 
                 if (this._copy.translateFromPivot) {
                     this._pivotBackTranslation.copyFromFloats(0.0, 0.0, 0.0);
                 }
                 else {
-                    this._pivotBackTranslation.copyFrom(this._copy.pivot);
+                    this._pivotBackTranslation.copyFrom(this._scaledPivot);
                 }
     
                 for (i = 0; i < shape.length; i++) {
@@ -420,9 +427,9 @@
                     this._vertex.y *= this._copy.scaling.y;
                     this._vertex.z *= this._copy.scaling.z;
 
-                    this._vertex.x -= this._copy.pivot.x;
-                    this._vertex.y -= this._copy.pivot.y;
-                    this._vertex.z -= this._copy.pivot.z;
+                    this._vertex.x -= this._scaledPivot.x;
+                    this._vertex.y -= this._scaledPivot.y;
+                    this._vertex.z -= this._scaledPivot.z;
     
                     Vector3.TransformCoordinatesToRef(this._vertex, this._rotMatrix, this._rotated);
 
@@ -582,11 +589,15 @@
                 }
                 this._quaternionToRotationMatrix();
 
+                this._scaledPivot.x = this._particle.pivot.x * this._particle.scaling.x;
+                this._scaledPivot.y = this._particle.pivot.y * this._particle.scaling.y;
+                this._scaledPivot.z = this._particle.pivot.z * this._particle.scaling.z;
+
                 if (this._copy.translateFromPivot) {
                     this._pivotBackTranslation.copyFromFloats(0.0, 0.0, 0.0);
                 }
                 else {
-                    this._pivotBackTranslation.copyFrom(this._copy.pivot);
+                    this._pivotBackTranslation.copyFrom(this._scaledPivot);
                 }
     
                 this._shape = particle._model._shape;
@@ -603,9 +614,9 @@
                     this._vertex.y *= this._copy.scaling.y;
                     this._vertex.z *= this._copy.scaling.z;
 
-                    this._vertex.x -= this._copy.pivot.x;
-                    this._vertex.y -= this._copy.pivot.y;
-                    this._vertex.z -= this._copy.pivot.z;
+                    this._vertex.x -= this._scaledPivot.x;
+                    this._vertex.y -= this._scaledPivot.y;
+                    this._vertex.z -= this._scaledPivot.z;
     
                     Vector3.TransformCoordinatesToRef(this._vertex, this._rotMatrix, this._rotated);
                     this._rotated.addInPlace(this._pivotBackTranslation);
@@ -624,6 +635,15 @@
                 particle.scaling.x = 1.0;
                 particle.scaling.y = 1.0;
                 particle.scaling.z = 1.0;
+                particle.uvs.x = 0.0;
+                particle.uvs.y = 0.0;
+                particle.uvs.z = 1.0;
+                particle.uvs.w = 1.0;
+                particle.pivot.x = 0.0;
+                particle.pivot.y = 0.0;
+                particle.pivot.z = 0.0;
+                particle.translateFromPivot = false;
+                particle.parentId = null;
             }
 
             /**
@@ -751,7 +771,12 @@
     
                     if (this._particle.isVisible) {
                         this._particle._stillInvisible = false; // un-mark permanent invisibility
-    
+                        this._particleHasParent = (this._particle.parentId !== null);
+
+                        this._scaledPivot.x = this._particle.pivot.x * this._particle.scaling.x;
+                        this._scaledPivot.y = this._particle.pivot.y * this._particle.scaling.y;
+                        this._scaledPivot.z = this._particle.pivot.z * this._particle.scaling.z;
+
                         // particle rotation matrix
                         if (this.billboard) {
                             this._particle.rotation.x = 0.0;
@@ -767,6 +792,34 @@
                                 this._quaternionRotationYPR();
                             }
                             this._quaternionToRotationMatrix();
+
+                        }
+
+                        if (this._particleHasParent) {
+                            this._parent = this.particles[this._particle.parentId!];
+                            this._rotated.x = this._particle.position.x * this._parent._rotationMatrix[0] + this._particle.position.y * this._parent._rotationMatrix[3] + this._particle.position.z * this._parent._rotationMatrix[6];
+                            this._rotated.y = this._particle.position.x * this._parent._rotationMatrix[1] + this._particle.position.y * this._parent._rotationMatrix[4] + this._particle.position.z * this._parent._rotationMatrix[7];
+                            this._rotated.z = this._particle.position.x * this._parent._rotationMatrix[2] + this._particle.position.y * this._parent._rotationMatrix[5] + this._particle.position.z * this._parent._rotationMatrix[8];
+
+                            this._particle._globalPosition.x = this._parent._globalPosition.x + this._rotated.x;
+                            this._particle._globalPosition.y = this._parent._globalPosition.y + this._rotated.y;
+                            this._particle._globalPosition.z = this._parent._globalPosition.z + this._rotated.z;
+
+                            this._particle._rotationMatrix[0] = this._rotMatrix.m[0] * this._parent._rotationMatrix[0] + this._rotMatrix.m[1] * this._parent._rotationMatrix[3] + this._rotMatrix.m[2] * this._parent._rotationMatrix[6];
+                            this._particle._rotationMatrix[1] = this._rotMatrix.m[0] * this._parent._rotationMatrix[1] + this._rotMatrix.m[1] * this._parent._rotationMatrix[4] + this._rotMatrix.m[2] * this._parent._rotationMatrix[7];
+                            this._particle._rotationMatrix[2] = this._rotMatrix.m[0] * this._parent._rotationMatrix[2] + this._rotMatrix.m[1] * this._parent._rotationMatrix[5] + this._rotMatrix.m[2] * this._parent._rotationMatrix[8];
+                            this._particle._rotationMatrix[3] = this._rotMatrix.m[4] * this._parent._rotationMatrix[0] + this._rotMatrix.m[5] * this._parent._rotationMatrix[3] + this._rotMatrix.m[6] * this._parent._rotationMatrix[6];
+                            this._particle._rotationMatrix[4] = this._rotMatrix.m[4] * this._parent._rotationMatrix[1] + this._rotMatrix.m[5] * this._parent._rotationMatrix[4] + this._rotMatrix.m[6] * this._parent._rotationMatrix[7];
+                            this._particle._rotationMatrix[5] = this._rotMatrix.m[4] * this._parent._rotationMatrix[2] + this._rotMatrix.m[5] * this._parent._rotationMatrix[5] + this._rotMatrix.m[6] * this._parent._rotationMatrix[8];
+                            this._particle._rotationMatrix[6] = this._rotMatrix.m[8] * this._parent._rotationMatrix[0] + this._rotMatrix.m[9] * this._parent._rotationMatrix[3] + this._rotMatrix.m[10] * this._parent._rotationMatrix[6];
+                            this._particle._rotationMatrix[7] = this._rotMatrix.m[8] * this._parent._rotationMatrix[1] + this._rotMatrix.m[9] * this._parent._rotationMatrix[4] + this._rotMatrix.m[10] * this._parent._rotationMatrix[7];
+                            this._particle._rotationMatrix[8] = this._rotMatrix.m[8] * this._parent._rotationMatrix[2] + this._rotMatrix.m[9] * this._parent._rotationMatrix[5] + this._rotMatrix.m[10] * this._parent._rotationMatrix[8];
+                        }
+                        else {
+                            this._particle._globalPosition.x = this._particle.position.x;
+                            this._particle._globalPosition.y = this._particle.position.y;
+                            this._particle._globalPosition.z = this._particle.position.z;
+
                             this._particle._rotationMatrix[0] = this._rotMatrix.m[0];
                             this._particle._rotationMatrix[1] = this._rotMatrix.m[1];
                             this._particle._rotationMatrix[2] = this._rotMatrix.m[2];
@@ -784,9 +837,9 @@
                             this._pivotBackTranslation.z = 0.0;
                         }
                         else {
-                            this._pivotBackTranslation.x = this._particle.pivot.x;
-                            this._pivotBackTranslation.y = this._particle.pivot.y;
-                            this._pivotBackTranslation.z = this._particle.pivot.z;
+                            this._pivotBackTranslation.x = this._scaledPivot.x;
+                            this._pivotBackTranslation.y = this._scaledPivot.y;
+                            this._pivotBackTranslation.z = this._scaledPivot.z;
                         }
                         // particle vertex loop
                         for (pt = 0; pt < this._shape.length; pt++) {
@@ -807,9 +860,9 @@
                             this._vertex.y *= this._particle.scaling.y;
                             this._vertex.z *= this._particle.scaling.z;
 
-                            this._vertex.x -= this._particle.pivot.x;
-                            this._vertex.y -= this._particle.pivot.y;
-                            this._vertex.z -= this._particle.pivot.z;
+                            this._vertex.x -= this._scaledPivot.x;
+                            this._vertex.y -= this._scaledPivot.y;
+                            this._vertex.z -= this._scaledPivot.z;
     
                             this._rotated.x = this._vertex.x * this._particle._rotationMatrix[0] + this._vertex.y * this._particle._rotationMatrix[3] + this._vertex.z * this._particle._rotationMatrix[6];
                             this._rotated.y = this._vertex.x * this._particle._rotationMatrix[1] + this._vertex.y * this._particle._rotationMatrix[4] + this._vertex.z * this._particle._rotationMatrix[7];
@@ -819,9 +872,9 @@
                             this._rotated.y += this._pivotBackTranslation.y;
                             this._rotated.z += this._pivotBackTranslation.z;
 
-                            this._positions32[idx] = this._particle.position.x + this._cam_axisX.x * this._rotated.x + this._cam_axisY.x * this._rotated.y + this._cam_axisZ.x * this._rotated.z;
-                            this._positions32[idx + 1] = this._particle.position.y + this._cam_axisX.y * this._rotated.x + this._cam_axisY.y * this._rotated.y + this._cam_axisZ.y * this._rotated.z;
-                            this._positions32[idx + 2] = this._particle.position.z + this._cam_axisX.z * this._rotated.x + this._cam_axisY.z * this._rotated.y + this._cam_axisZ.z * this._rotated.z;
+                            this._positions32[idx] = this._particle._globalPosition.x + this._cam_axisX.x * this._rotated.x + this._cam_axisY.x * this._rotated.y + this._cam_axisZ.x * this._rotated.z;
+                            this._positions32[idx + 1] = this._particle._globalPosition.y + this._cam_axisX.y * this._rotated.x + this._cam_axisY.y * this._rotated.y + this._cam_axisZ.y * this._rotated.z;
+                            this._positions32[idx + 2] = this._particle._globalPosition.z + this._cam_axisX.z * this._rotated.x + this._cam_axisY.z * this._rotated.y + this._cam_axisZ.z * this._rotated.z;
     
                             if (this._computeBoundingBox) {
                                 if (this._positions32[idx] < this._minimum.x) {
@@ -926,9 +979,9 @@
                         this._maxBbox.x = this._particle._modelBoundingInfo.maximum.x * this._particle.scaling.x;
                         this._maxBbox.y = this._particle._modelBoundingInfo.maximum.y * this._particle.scaling.y;
                         this._maxBbox.z = this._particle._modelBoundingInfo.maximum.z * this._particle.scaling.z;
-                        bSphere.center.x = this._particle.position.x + (this._minBbox.x + this._maxBbox.x) * 0.5;
-                        bSphere.center.y = this._particle.position.y + (this._minBbox.y + this._maxBbox.y) * 0.5;
-                        bSphere.center.z = this._particle.position.z + (this._minBbox.z + this._maxBbox.z) * 0.5;
+                        bSphere.center.x = this._particle._globalPosition.x + (this._minBbox.x + this._maxBbox.x) * 0.5;
+                        bSphere.center.y = this._particle._globalPosition.y + (this._minBbox.y + this._maxBbox.y) * 0.5;
+                        bSphere.center.z = this._particle._globalPosition.z + (this._minBbox.z + this._maxBbox.z) * 0.5;
                         bSphere.radius = this._bSphereRadiusFactor * 0.5 * Math.sqrt((this._maxBbox.x - this._minBbox.x) * (this._maxBbox.x - this._minBbox.x) + (this._maxBbox.y - this._minBbox.y) * (this._maxBbox.y - this._minBbox.y) + (this._maxBbox.z - this._minBbox.z) * (this._maxBbox.z - this._minBbox.z));
                         bSphere._update(this.mesh._worldMatrix);
                     }