diff --git a/data/tests/test_bsdf.xml b/data/tests/test_bsdf.xml
index 2abd7c4f..6fff9001 100644
--- a/data/tests/test_bsdf.xml
+++ b/data/tests/test_bsdf.xml
@@ -2,22 +2,6 @@
 	 to be tested for consistency. This is done
 	 using the testcase 'test_chisquare' -->
 <scene>
-	<!-- Test a smooth coating over a diffuse base material -->
-	<bsdf type="coating">
-		<float name="intIOR" value="1.5"/>
-		<float name="extIOR" value="1"/>
-		<rgb name="sigmaA" value="0.1 0.2 0.3"/>
-		<float name="thickness" value="2"/>
-		<bsdf type="diffuse"/>
-	</bsdf>
-
-	<!-- Test a smooth coating over a rough metal material -->
-	<bsdf type="coating">
-		<float name="intIOR" value="1.5"/>
-		<float name="extIOR" value="1"/>
-		<bsdf type="roughconductor"/>
-	</bsdf>
-
 	<!-- Test the smooth diffuse model -->
 	<bsdf type="diffuse"/>
 
@@ -142,10 +126,30 @@
 	<bsdf type="ward">
 		<float name="alphaU" value=".1"/>
 		<float name="alphaV" value=".3"/>
+		<spectrum name="diffuseReflectance" value="0.2"/>
+		<spectrum name="specularReflectance" value="0.4"/>
 	</bsdf>
 
-	<!-- Test the mask model -->
+	<!-- Test the mask model (with constant 50% opacity) -->
 	<bsdf type="mask">
+		<spectrum name="opacity" value="0.5"/>
+
 		<bsdf type="diffuse"/>
 	</bsdf>
+
+	<!-- Test the smooth coating over a diffuse base material -->
+	<bsdf type="coating">
+		<float name="intIOR" value="1.5"/>
+		<float name="extIOR" value="1"/>
+		<rgb name="sigmaA" value="0.1 0.2 0.3"/>
+		<float name="thickness" value="2"/>
+		<bsdf type="diffuse"/>
+	</bsdf>
+
+	<!-- Test the smooth coating over a rough metal material -->
+	<bsdf type="coating">
+		<float name="intIOR" value="1.5"/>
+		<float name="extIOR" value="1"/>
+		<bsdf type="roughconductor"/>
+	</bsdf>
 </scene>
diff --git a/doc/images/bsdf_conductor_copper.jpg b/doc/images/bsdf_conductor_copper.jpg
index c5a91ad0..7aef725d 100644
Binary files a/doc/images/bsdf_conductor_copper.jpg and b/doc/images/bsdf_conductor_copper.jpg differ
diff --git a/include/mitsuba/hw/basicshader.h b/include/mitsuba/hw/basicshader.h
index 3c2d5e62..62653cca 100644
--- a/include/mitsuba/hw/basicshader.h
+++ b/include/mitsuba/hw/basicshader.h
@@ -35,7 +35,7 @@ MTS_NAMESPACE_BEGIN
  *
  * Includes a \ref Shader implementation for hardware rendering
  */
-class MTS_EXPORT_RENDER ConstantSpectrumTexture : public Texture {
+class MTS_EXPORT_HW ConstantSpectrumTexture : public Texture {
 public:
 	inline ConstantSpectrumTexture(const Spectrum &value)
 		: Texture(Properties()), m_value(value) {
@@ -83,7 +83,7 @@ protected:
  *
  * Includes a \ref Shader implementation for hardware rendering
  */
-class MTS_EXPORT_RENDER ConstantFloatTexture : public Texture {
+class MTS_EXPORT_HW ConstantFloatTexture : public Texture {
 public:
 	inline ConstantFloatTexture(const Float &value)
 		: Texture(Properties()), m_value(value) {