Updated tests

Author: leroyvn

src/sensors/tests/test_radiancemeter.py

@@ -123,6 +123,43 @@ def test_sample_ray(variant_scalar_rgb, direction, origin):
     ray = sensor.sample_ray_differential(1., 1., sample2, sample1, True)
     assert ek.allclose(ray[0].o, origin)
     assert ek.allclose(ray[0].d, ek.normalize(direction))
-    assert ray[0].has_differentials
-    assert ek.allclose(ray[0].d_x, 0.)
-    assert ek.allclose(ray[0].d_y, 0.)
+    assert not ray[0].has_differentials
+
+
+@pytest.mark.parametrize("radiance", [10**x for x in range(-3, 4)])
+def test_render(variant_scalar_rgb, radiance):
+    # Test render results with a simple scene
+    from mitsuba.core.xml import load_string
+    import numpy as np
+
+    scene_xml = """
+    <scene version="2.0.0">
+        <default name="radiance" value="1.0"/>
+        <default name="spp" value="1"/>
+
+        <integrator type="path"/>
+
+        <sensor type="radiancemeter">
+            <film type="hdrfilm">
+                <integer name="width" value="1"/>
+                <integer name="height" value="1"/>
+                <string name="pixel_format" value="rgb"/>
+                <rfilter type="box"/>
+            </film>
+
+            <sampler type="independent">
+                <integer name="sample_count" value="$spp"/>
+            </sampler>
+        </sensor>
+
+        <emitter type="constant">
+            <spectrum name="radiance" value="$radiance"/>
+        </emitter>
+    </scene>
+    """
+
+    scene = load_string(scene_xml, spp=1, radiance=radiance)
+    sensor = scene.sensors()[0]
+    scene.integrator().render(scene, sensor)
+    img = sensor.film().bitmap()
+    assert np.allclose(np.array(img), radiance)