Merge pull request #13993 from mikialex/dev

Fast Box3 applyMatrix4

src/math/Box3.js

@@ -559,41 +559,47 @@ Object.assign( Box3.prototype, {
 
 	},
 
-	applyMatrix4: function () {
-
-		var points = [
-			new Vector3(),
-			new Vector3(),
-			new Vector3(),
-			new Vector3(),
-			new Vector3(),
-			new Vector3(),
-			new Vector3(),
-			new Vector3()
-		];
-
-		return function applyMatrix4( matrix ) {
-
-			// transform of empty box is an empty box.
-			if ( this.isEmpty() ) return this;
-
-			// NOTE: I am using a binary pattern to specify all 2^3 combinations below
-			points[ 0 ].set( this.min.x, this.min.y, this.min.z ).applyMatrix4( matrix ); // 000
-			points[ 1 ].set( this.min.x, this.min.y, this.max.z ).applyMatrix4( matrix ); // 001
-			points[ 2 ].set( this.min.x, this.max.y, this.min.z ).applyMatrix4( matrix ); // 010
-			points[ 3 ].set( this.min.x, this.max.y, this.max.z ).applyMatrix4( matrix ); // 011
-			points[ 4 ].set( this.max.x, this.min.y, this.min.z ).applyMatrix4( matrix ); // 100
-			points[ 5 ].set( this.max.x, this.min.y, this.max.z ).applyMatrix4( matrix ); // 101
-			points[ 6 ].set( this.max.x, this.max.y, this.min.z ).applyMatrix4( matrix ); // 110
-			points[ 7 ].set( this.max.x, this.max.y, this.max.z ).applyMatrix4( matrix );	// 111
-
-			this.setFromPoints( points );
+	applyMatrix4: function applyMatrix4( matrix ) {
 
-			return this;
+		// transform of empty box is an empty box.
+		if ( this.isEmpty( ) ) return this;
 
-		};
+		var m = matrix.elements;
 
-	}(),
+		var xax = m[ 0 ] * this.min.x;
+		var xay = m[ 1 ] * this.min.x;
+		var xaz = m[ 2 ] * this.min.x;
+
+		var xbx = m[ 0 ] * this.max.x;
+		var xby = m[ 1 ] * this.max.x;
+		var xbz = m[ 2 ] * this.max.x;
+
+		var yax = m[ 4 ] * this.min.y;
+		var yay = m[ 5 ] * this.min.y;
+		var yaz = m[ 6 ] * this.min.y;
+
+		var ybx = m[ 4 ] * this.max.y;
+		var yby = m[ 5 ] * this.max.y;
+		var ybz = m[ 6 ] * this.max.y;
+
+		var zax = m[ 8 ] * this.min.z;
+		var zay = m[ 9 ] * this.min.z;
+		var zaz = m[ 10 ] * this.min.z;
+
+		var zbx = m[ 8 ] * this.max.z;
+		var zby = m[ 9 ] * this.max.z;
+		var zbz = m[ 10 ] * this.max.z;
+
+		this.min.x = Math.min( xax, xbx ) + Math.min( yax, ybx ) + Math.min( zax, zbx ) + m[ 12 ];
+		this.min.y = Math.min( xay, xby ) + Math.min( yay, yby ) + Math.min( zay, zby ) + m[ 13 ];
+		this.min.z = Math.min( xaz, xbz ) + Math.min( yaz, ybz ) + Math.min( zaz, zbz ) + m[ 14 ];
+		this.max.x = Math.max( xax, xbx ) + Math.max( yax, ybx ) + Math.max( zax, zbx ) + m[ 12 ];
+		this.max.y = Math.max( xay, xby ) + Math.max( yay, yby ) + Math.max( zay, zby ) + m[ 13 ];
+		this.max.z = Math.max( xaz, xbz ) + Math.max( yaz, ybz ) + Math.max( zaz, zbz ) + m[ 14 ];
+
+		return this;
+
+	},
 
 	translate: function ( offset ) {