- Add test scene file to the data/ folder.
- Fix rt.color representation and operators.
- Make Environment default-constructible and implementing JsonDeserializer.
- Make the Intersectable interface members const.
- Make Geometry's Intersectable methods const. SHOULD investigate about storing reference in the IntersectionData. Need to somehow use tail-const.
- Add bucketSize field to GlobalSettings and make frame size, maxTraceDepth, maxTraceDepth uint and numThreads size_t. Rename properties and improve comments. Also add adjustFrameSize method to make the frame size multiple of the bucketSize.
- Make Texture's Intersectable methods const and add Checker.toString.
- Make Light's Intersectable methods const and change numSamples and NthSample to use size_t.
- Make Node's Intersectable methods const and remove  debug stdout printing.
- Make Shader's Intersectable, BRDF and IShader methods const. Add reference to the scene while deserializing, add call counting for Lambert's shade(..), eval(..) and spawnRay(..) methods.
- Add Scene reference to the SceneLoadContext while deserializing, add Environment deserialization, adjust ray flags in testVisibility(..) by adding shadow. Remove unneeded code for beginRender(..) and beginFrame(..).
- Set init values for Camera's properties, fix vector * matrix multiplication, get frame size while deserializing and calculate aspect ration, add missing deserialization for some properties, make getScreenRay(..) const and fix casts for DMD 2.065 compatibility.
- Make importing of std.json in sceneloader.d public and remove importing of std.json from camera.d, geometry.d, globalsettings.d, light.d, node.d, scene.d, shader.d and texture.d. Add exception handling to parseSceneFromFile. Add reference to the Scene in the SceneLoadContext. Fix checking for key in JSONValue for DMD 2.065 compatability.
- Encapsulate rendering methods in a Renderer class. Add AA rendering. Extract BUCKET_SIZE and make it configurable setting. Change for -> foreach in several places. Fix const and int -> size_t. Fix renamed properties.
- Add Lambert shader call count diagnostics in app.d.