{
  "scene": {
    "aggregate": {
      "type": "PrimitiveList",
      "primitives": [
        {
          "_include": "cornell_hallway_scene.json"
        },
        {
          "_comment": "Sensors.",
          "type": "PointPrimitive",
          "position": [0, -0.5, 0],
          "sensors": [
            {
              "_comment": "Towards back wall.",
              "type": "PinholeCamera",
              "outputPath": "cornell_hallway_particle_tracer.png",
              "target":   [0, 1, 0],
              "up":       [0, 0, 1],
              "fov": 82,
              "width": 320,
              "height": 240,
              "samplesPerPixel": 32
            }
          ]
        }
      ]
    }
  },

  "renderer": {
    "type": "ParticleTracingRenderer",
    "pathType": "directSensor",
    "russianRouletteMethod": "proportional",
    "russianRouletteStartIndex": 5,
    "russianRouletteMaxProbability": 0.95,
    "russianRouletteDelta": 0.25,
    "maxEdgeCount": 100,
    "sampler": {
      "type": "IndependentSampler"
    }
  }
}

{
  "scene": {
    "aggregate": {
      "type": "PrimitiveList",
      "primitives": [
        {
          "_include": "cornell_hallway_scene.json"
        },
        {
          "_comment": "Camera.",
          "type": "GeometricPrimitive",
          "shape": {
            "type": "Disk",
            "center": [ 0, -0.5, 0 ],
            "normal": [ 0, 1, 0 ],
            "radius": 0.05
          },
          "material": {
            "type": "DiffuseMaterial",
            "samplingMethod": "cosine",
            "rho": { "type": "rgb", "r": 0.0, "g": 0.0, "b": 0.0 }
          },
          "sensors": [
            {
              "_comment": "Towards back wall.",
              "type": "ThinLensCamera",
              "outputPath": "cornell_hallway_particle_tracer.png",
              "up": [0, 0, 1],
              "fov": 82,
              "frontFocalLength": 2,
              "width": 320,
              "height": 240,
              "samplesPerPixel": 32
            }
          ]
        }
      ]
    }
  },

  "renderer": {
    "type": "ParticleTracingRenderer",
    "pathType": "emittedImportance",
    "russianRouletteMethod": "proportional",
    "russianRouletteStartIndex": 5,
    "russianRouletteMaxProbability": 0.95,
    "russianRouletteDelta": 0.25,
    "maxEdgeCount": 100,
    "sampler": {
      "type": "IndependentSampler"
    }
  }
}

Make Cornell hallway scene (particle tracer) use thin lens camera
Make Cornell hallway scene (particle tracer) use thin lens camera

Use emittedImportance path type for now.
