We are inspired by this first image of aeroplane, and considering to combine this with some features shown in the second image. The beautiful colour displayed out from the smoke vortex line filaments generated by the plane impressed us a lot, and so we would like to render the similar phenomenon with our stylization. In addition, to highlight the colour and remark the “lines” in this case, we would like to create as well some detail-preserved shining and glistening effect within the volumetric medium.
(#) Proposed features and points
We implemented the following features:
* Volumetric path tracing with homogenous and heterogenous media with coloring (4-8 pts)
* Photon mapping with global photon map, caustic photon map and final gathering (4-8 pts)
* Environment Map with importance sampling (2-4 pts)
* Microfacet Anisotropic BRDF (2-4 pts)
* Directional Light (1-2 pts)
* Depth of field (1-2 pts)
* Transformation of texture (1-2 pts)
(##) Division of collaboration
We implemented volumetric path tracing, transformation of texture, depth of field together.
Diyang Zhang implemented microfacet anisotropic BRDF and all the modeling needed for showcase and validation tests.
Duowen Chen implemented photon mapping, environmenet map and sun light.
We consider this to be a equal disttribution of work.
(#) Validation for results
(##) VPT with homogenous and heterogenous media with coloring:
We first show our implementaion of homogenous media. We use the implementation provided from slides that sample distance is generated from a power disttribution
mapped from a uniform random number. Then we implemented MIS style integrator given the pesudo code from slides:
For homo media, the implementation is in `media/homogenous.cpp` and `integrator/path_tracer_volume.cpp`
We show effect of this below:
For sun light, the implementation is in `material/direct_light.cpp`
With directional light (sun light) implementation, we also have the following effect:
We then show our implementation for heterogenous media where we adopt the null particle scattering scheme from lecture slides.
We also used a MIS style integrator for heterogenous media:
We show effect below:
Effect with color:
(##) Environment Map with importance sampling
We implemented environmenet map as a diffuse lightsource with a new surface object. We use importance sampling scheme from lecture give below:
(##) Photon mapping with global photon map, caustic photon map and final gathering
We implemented photon mapping with lecture suggestion as follows. We implement photon mapping where we break them to four parts:
1. Direct Illumination, 2. Global Photon Map, 3. Caustic Photon Map, 4. Emission
We store photon in a KD-Tree structure provided and we use a KNN estimation for Radience estimation and exclude caustic photon map from global photon map where the path is not LS+D (gloabl only store path not LS+D and caustic only LS+D).
Below we show our result below:
(##) Microfacet Anisotropic BRDF
We implemented method for Anisotropic interfaced Lambertian microfacets material. We estimated the microfacet distribution function based on a Gaussian distribution
of microfacet slopes due to Beckmann and Spizzichino (1963).
We show our result below:
(##) Directional Light
For Directional Light, we just impelemented because of the inspiration from the lecture slide of this one:
(##) Depth of field
We implemented depth of field and result is shown below:
(##) Transformation of texture
We implemented transformation of texture which was mentioned in previous assignment as an optional feature:
(#) Showcase image -- Color outside the lines:
Due to time limit, we are don't able to get a low resolution version.
The idea accord to color outside lines is that:
* A line of color formed from the blue smoke
* This doesn't exist within real word guidelines
* This is outside the horizon which is another form of outside the lines
* Pokemon Charizard should spits fire but we use a blue smoke to represent water which is not accord to the setting of Pokemon
