CIS565-Fall-2019 · ZheyuanXie · Sep 28, 2019 · Sep 28, 2019 · Sep 29, 2019 · Sep 29, 2019
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -73,6 +73,7 @@ set(headers
     src/sceneStructs.h
     src/preview.h
     src/utilities.h
+    src/tiny_obj_loader.h
     )
 
 set(sources
@@ -84,6 +85,7 @@ set(sources
     src/scene.cpp
     src/preview.cpp
     src/utilities.cpp
+    src/tiny_obj_loader.cc
     )
 
 list(SORT headers)

diff --git a/README.md b/README.md
@@ -3,11 +3,86 @@ CUDA Path Tracer
 
 **University of Pennsylvania, CIS 565: GPU Programming and Architecture, Project 3**
 
-* (TODO) YOUR NAME HERE
-* Tested on: (TODO) Windows 22, i7-2222 @ 2.22GHz 22GB, GTX 222 222MB (Moore 2222 Lab)
+* Zheyuan Xie
+* Tested on: Windows 10 Pro, i7-7700HQ @ 2.80GHz, 16GB, GTX 1050 2GB (Dell XPS 15 9560)
 
-### (TODO: Your README)
+## Introduction
+![path tracer demo](img/banner.png)
 
-*DO NOT* leave the README to the last minute! It is a crucial part of the
-project, and we will not be able to grade you without a good README.
+This is a CUDA-based path tracer capable of rendering globally-illuminated images very quickly.
 
+## Features
+### 1 Arbitrary Mesh Loading
+The path tracer loads arbitrary mesh object from .obj files using [tinyObj](http://syoyo.github.io/tinyobjloader/). Loaded triangles and precomputed surface normals are stored in an addtional device buffer which can be quickly accessed.
+
+| Bunny | Diamond | City |
+|--|--|--|
+|![](img/bunny_diffuse.png) | ![](img/diamond.png) | ![](img/city.png) |
+
+### 2 Refraction with Frensel Effects
+Refraction with Frensel effects using Schlick's approximation.
+
+| Perfect Speculer | Transmissive | Diffussive |
+|--|--|--|
+|![perfect speculer](img/speculer.png) | ![refractive](img/transmissive.png) | ![pure diffusive](img/diffusive.png) |
+
+### 3 Physically-Based Depth-of-Field
+Physically-based depth-of-field is achieved by simulating camera lens. Instead of using the pinhole camera model, we apply the thin lens approximation model. [PBRT 6.2.3]
+
+The images below shows three renderings of one scene. The camera is focused at the frontmost sphere. Larger lens radius results in a deeper depth of field.
+
+| DOF OFF | DOF ON (LR=0.5) | DOF ON (LR=2.0) |
+|--|--|--|
+|![](img/dof_off.png) | ![](img/dof_lr05.png) | ![](img/dof_lr20.png) |
+
+### 4 Stochastic Sampled Antialiasing
+Anti-Aliasing is achieved by randomly jittering ray within the pixel and average the results of multiple rays.
+
+| Antialiasing OFF | Antialiasing ON|
+|--|--|
+|![](img/aa_off.png) | ![](img/aa_on.png) |
+
+### 5 Camera Motion Blur
+Camera motion blur is achieved by randomly jittering rays along the direction of motion.
+
+| Static Camera | Rightward Motion | Forward Motion |
+|--|--|--|
+|![](img/speculer.png) | ![](img/motion_blur_right.png) | ![](img/motion_blur_forward.png) |
+
+## Optimization
+The following optimization methods are implemented to reduce rendering time:
+ - **Stream Compaction:** Remove completed rays, reducing the number of threads to launch.
+ - **Cache First Iteraction:** Cache the first bounce intersections for re-use across all subsequent iterations.
+ - **Sort Materials:** Sort the rays/path segments so that rays/paths interacting with the same material are contiguous in memory before shading.
+ - **Bounding Volume Intersection Culling:** Reduce the number of rays that have to be checked against the entire mesh by first checking rays against a volume that completely bounds the mesh. This optimization does not apply to primitive shapes.
+
+We compare rendering performance with different optimization methods enabled.
+ - NO = No Optimization
+ - CF = Cache First iteration only
+ - SC = Stream Compaction only
+ - SM = Sort Materials only
+ - IC = Bounding Volume Intersection Culling only
+ - SC+IC+CF = Three optimizations combined
+ - ALL = All Optimization
+
+For a basic scene consists of a cornell box and four primitive shapes (spheres and boxes). Counterintuitively, the render time is minimized with no optimization. The probable cause is the kernel launch overhead for sorting and reduction.
+
+![](img/perf_basic.png)
+
+For a more complex scene consists of a cornell box and a Stanford bunny, optimizations reduce rendering time by almost 50%.
+
+![](img/perf_bunny.png)
+
+## Bloopers
+
+![](img/blooper1.png)
+
+![](img/blooper2.png)
+
+![](img/blooper3.png)
+
+
+## Reference
+ - Physically Based Rendering, Third Edition: From Theory To Implementation. Pharr, Matt and Humphreys, Greg.
+ - Project 3 Recitation - Hannah ([link](https://docs.google.com/presentation/d/1bFtutDe9POZDPiqD9npeOEOWh783xHy4xf2AdJt-pEI/edit?usp=sharing))
+ - Most Efficient AABB vs Ray Collision Algorithms. ([link](https://gamedev.stackexchange.com/questions/18436/most-efficient-aabb-vs-ray-collision-algorithms))
diff --git a/img/aa_off.png b/img/aa_off.png
diff --git a/img/aa_on.png b/img/aa_on.png
diff --git a/img/banner.png b/img/banner.png
diff --git a/img/blooper1.png b/img/blooper1.png
diff --git a/img/blooper2.png b/img/blooper2.png
diff --git a/img/blooper3.png b/img/blooper3.png
diff --git a/img/bunny_diffuse.png b/img/bunny_diffuse.png
diff --git a/img/bunny_refract.png b/img/bunny_refract.png
diff --git a/img/city.png b/img/city.png
diff --git a/img/diamond.png b/img/diamond.png
diff --git a/img/diffusive.png b/img/diffusive.png
diff --git a/img/dof_lr05.png b/img/dof_lr05.png
diff --git a/img/dof_lr20.png b/img/dof_lr20.png
diff --git a/img/dof_off.png b/img/dof_off.png
diff --git a/img/motion_blur_forward.png b/img/motion_blur_forward.png
diff --git a/img/motion_blur_right.png b/img/motion_blur_right.png
diff --git a/img/perf_basic.png b/img/perf_basic.png
diff --git a/img/perf_bunny.png b/img/perf_bunny.png
diff --git a/img/speculer.png b/img/speculer.png
diff --git a/img/transmissive.png b/img/transmissive.png
diff --git a/scenes/bunny.txt b/scenes/bunny.txt
@@ -0,0 +1,142 @@
+// Emissive material (light)
+MATERIAL 0
+RGB         1 1 1
+SPECEX      0
+SPECRGB     0 0 0
+REFL        0
+REFR        0
+REFRIOR     0
+EMITTANCE   5
+
+// Diffuse white
+MATERIAL 1
+RGB         .98 .98 .98
+SPECEX      0
+SPECRGB     0 0 0
+REFL        0
+REFR        0
+REFRIOR     0
+EMITTANCE   0
+
+// Diffuse left wall
+MATERIAL 2
+RGB         .37 .30 .54
+SPECEX      0
+SPECRGB     0 0 0
+REFL        0
+REFR        0
+REFRIOR     0
+EMITTANCE   0
+
+// Diffuse right wall
+MATERIAL 3
+RGB         .98 .46 .41
+SPECEX      0
+SPECRGB     0 0 0
+REFL        0
+REFR        0
+REFRIOR     0
+EMITTANCE   0
+
+// Specular white
+MATERIAL 4
+RGB         .98 .98 .98
+SPECEX      0
+SPECRGB     .98 .98 .98
+REFL        1
+REFR        0
+REFRIOR     0
+EMITTANCE   0
+
+// Refractive white
+MATERIAL 5
+RGB         .98 .98 .98
+SPECEX      0
+SPECRGB     .98 .98 .98
+REFL        0
+REFR        1
+REFRIOR     1.33
+EMITTANCE   0
+
+// Bunny material
+MATERIAL 6
+RGB         .98 .98 .98
+SPECEX      0
+SPECRGB     .98 .98 .98
+REFL        0
+REFR        0
+REFRIOR     2.4
+EMITTANCE   0
+
+// Camera
+CAMERA
+RES         800 800
+FOVY        45
+ITERATIONS  3000
+DEPTH       8
+FILE        cornell
+EYE         0 5 10.5
+LOOKAT      0 5 0
+UP          0 1 0
+DOF         0
+LENSR       2.0
+FD          7.5
+AA          0
+MOTION	    0 0 0
+
+// Ceiling light
+OBJECT 0
+cube
+material 0
+TRANS       0 10 0
+ROTAT       0 0 0
+SCALE       3 .3 3
+
+// Floor
+OBJECT 1
+cube
+material 1
+TRANS       0 0 0
+ROTAT       0 0 0
+SCALE       10 .01 10
+
+// Ceiling
+OBJECT 2
+cube
+material 1
+TRANS       0 10 0
+ROTAT       0 0 90
+SCALE       .01 10 10
+
+// Back wall
+OBJECT 3
+cube
+material 1
+TRANS       0 5 -5
+ROTAT       0 90 0
+SCALE       .01 10 10
+
+// Left wall
+OBJECT 4
+cube
+material 2
+TRANS       -5 5 0
+ROTAT       0 0 0
+SCALE       .01 10 10
+
+// Right wall
+OBJECT 5
+cube
+material 3
+TRANS       5 5 0
+ROTAT       0 0 0
+SCALE       .01 10 10
+
+// Bunny
+OBJECT 6
+mesh
+../scenes/bunny.obj
+material 6
+TRANS       0 -0.1 0
+ROTAT       0 0 0
+SCALE       4 4 4