Updated builds.

Author: mrdoob

build/three.js

@@ -21280,6 +21280,7 @@
 	 * Assumes 2 cameras that are parallel and share an X-axis, and that
 	 * the cameras' projection and world matrices have already been set.
 	 * And that near and far planes are identical for both cameras.
+	 * Visualization of this technique: https://computergraphics.stackexchange.com/a/4765
 	 */
 	function setProjectionFromUnion( camera, cameraL, cameraR ) {
 
@@ -21293,23 +21294,21 @@
 
 		// VR systems will have identical far and near planes, and
 		// most likely identical top and bottom frustum extents.
-		// via: https://computergraphics.stackexchange.com/a/4765
+		// Use the left camera for these values.
 		var near = projL[ 14 ] / ( projL[ 10 ] - 1 );
 		var far = projL[ 14 ] / ( projL[ 10 ] + 1 );
+		var topFov = ( projL[ 9 ] + 1 ) / projL[ 5 ];
+		var bottomFov  = ( projL[ 9 ] - 1 ) / projL[ 5 ];
 
-		var leftFovL = ( projL[ 8 ] - 1 ) / projL[ 0 ];
-		var rightFovR = ( projR[ 8 ] + 1 ) / projR[ 0 ];
-		var leftL = near * leftFovL;
-		var rightR = near * rightFovR;
-		var topL = near * ( projL[ 9 ] + 1 ) / projL[ 5 ];
-		var topR = near * ( projR[ 9 ] + 1 ) / projR[ 5 ];
-		var bottomL = near * ( projL[ 9 ] - 1 ) / projL[ 5 ];
-		var bottomR = near * ( projR[ 9 ] - 1 ) / projR[ 5 ];
+		var leftFov = ( projL[ 8 ] - 1 ) / projL[ 0 ];
+		var rightFov = ( projR[ 8 ] + 1 ) / projR[ 0 ];
+		var left = near * leftFov;
+		var right = near * rightFov;
 
 		// Calculate the new camera's position offset from the
 		// left camera. xOffset should be roughly half `ipd`.
-		var zOffset = ipd / ( - leftFovL + rightFovR );
-		var xOffset = zOffset * - leftFovL;
+		var zOffset = ipd / ( - leftFov + rightFov );
+		var xOffset = zOffset * - leftFov;
 
 		// TODO: Better way to apply this offset?
 		cameraL.matrixWorld.decompose( camera.position, camera.quaternion, camera.scale );
@@ -21323,12 +21322,12 @@
 		// although must now be relative to the new union camera.
 		var near2 = near + zOffset;
 		var far2 = far + zOffset;
-		var left = leftL - xOffset;
-		var right = rightR + ( ipd - xOffset );
-		var top = Math.max( topL, topR );
-		var bottom = Math.min( bottomL, bottomR );
+		var left2 = left - xOffset;
+		var right2 = right + ( ipd - xOffset );
+		var top2 = topFov * far / far2 * near2;
+		var bottom2 = bottomFov * far / far2 * near2;
 
-		camera.projectionMatrix.makePerspective( left, right, top, bottom, near2, far2 );
+		camera.projectionMatrix.makePerspective( left2, right2, top2, bottom2, near2, far2 );
 
 	}