Index: head/math/py-yt/Makefile
===================================================================
--- head/math/py-yt/Makefile	(revision 525711)
+++ head/math/py-yt/Makefile	(revision 525712)
@@ -1,39 +1,52 @@
 # Created by: Yuri Victorovich <yuri@rawbw.com>
 # $FreeBSD$
 
 PORTNAME=	yt
 DISTVERSION=	3.5.0
 PORTREVISION=	4
 CATEGORIES=	math astro python
 MASTER_SITES=	CHEESESHOP
 PKGNAMEPREFIX=	${PYTHON_PKGNAMEPREFIX}
 
 MAINTAINER=	yuri@FreeBSD.org
 COMMENT=	Analysis and visualization toolkit for volumetric data
 
 LICENSE=	BSD3CLAUSE
 LICENSE_FILE=	${WRKSRC}/COPYING.txt
 
-BUILD_DEPENDS=	${PYNUMPY} \
-		${PYTHON_PKGNAMEPREFIX}pyembree>0:graphics/py-pyembree@${PY_FLAVOR}
-LIB_DEPENDS=	libembree.so:graphics/embree \
-		libomp.so:devel/openmp
+BUILD_DEPENDS=	${PYNUMPY}
+LIB_DEPENDS=	libomp.so:devel/openmp
 RUN_DEPENDS=	${PYTHON_PKGNAMEPREFIX}sympy>=1.0:math/py-sympy@${PY_FLAVOR} \
 		${PYNUMPY} \
-		${PYTHON_PKGNAMEPREFIX}pyembree>0:graphics/py-pyembree@${PY_FLAVOR} \
 		${PYTHON_PKGNAMEPREFIX}matplotlib>=1.5.3:math/py-matplotlib@${PY_FLAVOR} \
 		${PYTHON_PKGNAMEPREFIX}ipython5>=1.0:devel/ipython5@${PY_FLAVOR}
 
 USES=		dos2unix localbase python
 USE_PYTHON=	distutils cython autoplist concurrent
 
+OPTIONS_DEFINE=	EMBREE
+OPTIONS_DEFAULT=	EMBREE
+EMBREE_DESC=	Embree ray-tracing engine support
+
+EMBREE_BUILD_DEPENDS=	${PYTHON_PKGNAMEPREFIX}pyembree>0:graphics/py-pyembree@${PY_FLAVOR}
+EMBREE_LIB_DEPENDS=	libembree.so:graphics/embree
+EMBREE_RUN_DEPENDS=	${EMBREE_BUILD_DEPENDS}
+
+post-patch-EMBREE-on:
+	@${REINPLACE_CMD} -e "s|check_for_pyembree() is not None|True|" \
+		${WRKSRC}/setup.py
+
+post-patch-EMBREE-off:
+	@${REINPLACE_CMD} -e "s|check_for_pyembree() is not None|False|" \
+		${WRKSRC}/setup.py
+
 post-patch:
-	@${REINPLACE_CMD} -e "s|check_for_pyembree() is not None|True|; s|check_for_openmp() is True|True|" \
+	@${REINPLACE_CMD} -e "s|check_for_openmp() is True|True|" \
 		${WRKSRC}/setup.py
 	@${REINPLACE_CMD} -e "s|\['-fopenmp', filename\]|['-I${LOCALBASE}/include', '-L${LOCALBASE}/lib', '-lm', '-fopenmp', filename]|" \
 		${WRKSRC}/setupext.py
 
 post-install:
 	@${STRIP_CMD} $$(${FIND} ${STAGEDIR}${PYTHON_SITELIBDIR} -name "*.so")
 
 .include <bsd.port.mk>