CIS565-Fall-2021 · JiyuHuang · Jan 16, 2021 · Sep 10, 2021 · Sep 10, 2021 · Sep 18, 2021
diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -86,16 +86,34 @@ set(sources
     src/utilities.cpp
     )
 
+set(imgui
+    imgui/imconfig.h
+    imgui/imgui.cpp
+    imgui/imgui.h
+    imgui/imgui_draw.cpp
+    imgui/imgui_internal.h
+    imgui/imgui_widgets.cpp
+    imgui/imgui_demo.cpp
+    imgui/imgui_impl_glfw.cpp
+    imgui/imgui_impl_glfw.h
+    imgui/imgui_impl_opengl2.cpp
+    imgui/imgui_impl_opengl2.h
+    imgui/imgui_impl_opengl3.cpp
+    imgui/imgui_impl_opengl3.h
+    )
+
 list(SORT headers)
 list(SORT sources)
+list(SORT imgui)
 
 source_group(Headers FILES ${headers})
 source_group(Sources FILES ${sources})
+source_group(imgui FILES ${imgui})
 
-#add_subdirectory(stream_compaction)  # TODO: uncomment if using your stream compaction
+add_subdirectory(stream_compaction)  # TODO: uncomment if using your stream compaction
 
-cuda_add_executable(${CMAKE_PROJECT_NAME} ${sources} ${headers})
+cuda_add_executable(${CMAKE_PROJECT_NAME} ${sources} ${headers} ${imgui})
 target_link_libraries(${CMAKE_PROJECT_NAME}
     ${LIBRARIES}
-    #stream_compaction  # TODO: uncomment if using your stream compaction
+    stream_compaction  # TODO: uncomment if using your stream compaction
     )
diff --git a/INSTRUCTION.md b/INSTRUCTION.md
diff --git a/README.md b/README.md
@@ -1,13 +1,93 @@
-CUDA Path Tracer
+CUDA Denoiser For CUDA Path Tracer
 ================
 
-**University of Pennsylvania, CIS 565: GPU Programming and Architecture, Project 3**
+**University of Pennsylvania, CIS 565: GPU Programming and Architecture, Project 4**
 
-* (TODO) YOUR NAME HERE
-* Tested on: (TODO) Windows 22, i7-2222 @ 2.22GHz 22GB, GTX 222 222MB (Moore 2222 Lab)
+* Jiyu Huang
+* Tested on: Windows 10, AMD Ryzen 7 5800H @ 3.20GHz 16GB, RTX 3070 Laptop 8GB
 
-### (TODO: Your README)
+| 10 iterations, no denoising | 10 iterations, denoised |
+| --------------------------- | ----------------------- |
+| ![](img/no-denoise.png)     | ![](img/denoised.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 project builds on top of the [CUDA path tracer](https://github.com/JiyuHuang/Project3-CUDA-Path-Tracer) project, and implements an edge-avoiding A-Trous wavelet transform for image denoising. The technique is described in detail in https://jo.dreggn.org/home/2010_atrous.pdf.
 
+# Analysis
+
+The default scene used for performance analysis can be found at [scenes/cornell_ceiling_light.txt](scenes/cornell_ceiling_light.txt), with a camera resolution of 800x800. The optimal block size chosen for A-Trous filter CUDA kernel is 32x32. The default filter size chosen is 65.
+
+## Denoising Time vs Path-Tracing Time
+
+Path-tracing and denoising times and measured by taking the average of ten executions. Ten iterations are performed in each execution. As seen from below, denoising using A-Trous wavelet transform takes relatively little amount of time compared to one iteration of path-tracing. When performed after several iterations of path-tracing, A-Trous denoising takes almost no overhead.
+
+![](img/chart-pathtrace-denoise.png)
+
+## Image Comparison
+
+| no denoising, 10 iterations | no denoising, 40 iterations | no denoising, 100 iterations |
+| ----------------------- | ---------------------------- | ----------------------------- |
+| ![](img/no-denoise.png)   | ![](img/cornell-40samp.png) |![](img/cornell-100samp.png)  |
+
+| denoised, 1 iteration | denoised, 4 iterations | denoised, 10 iterations |
+| ----------------------- | ---------------------------- | ----------------------------- |
+| ![](img/denoised-1samp.png) | ![](img/denoised-4samp.png) |![](img/denoised.png)  |
+
+As seen from the tables, it takes roughly 100 iterations to get a smooth image without denoising, and even after 100 iterations, the result image still has noise if looked closely. To get cleaner image, the iteration number increases quadratically.
+
+On the other hand, a denoised image looks smooth even with only one iteration, with the catch being that the image has color blob artifacts. At 10 iterations, the artifacts get reduced and the result is an acceptably smooth image.
+
+## Camera Resolution and Denoising Time
+
+The relationship between camera resolution and denoising time is as expected: run time increases as screen size (n x n) increases.
+
+![](img/chart-resolution.png)
+
+## Filter Size and Denoising Time
+
+Denoising time increases logarithmically as filter size increases. This is due to the fact that for the A-Trous wavelet transform, in each level the step width multiplies by 2. Therefore, the number of levels for the wavelet transform increases logarithmically.
+
+![](img/chart-filtersize.png)
+
+## Filter Size and Image Quality
+
+| filter size: 5           | filter size: 9            | filter size: 17            |
+| ------------------------ | ------------------------- | -------------------------- |
+|![](img/filtersize-5.png) | ![](img/filtersize-9.png) | ![](img/filtersize-17.png) |
+
+| filter size: 33            | filter size: 65       | filter size: 129            |
+| -------------------------- | --------------------- | --------------------------- |
+| ![](img/filtersize-33.png) | ![](img/denoised.png) | ![](img/filtersize-129.png) |
+
+Increaing filter size improves image quality, but the quality benefit gets smaller as filter size increases.
+
+## Limitation: Reflective/Refractive Materials, Uneven Lighting
+
+The edge-avoiding A-Trous filter uses position and normal information in its G-buffer to avoid blurring edges. For reflective or refractive materials, the filter can't effectively detect the edges in the reflection/refraction, and will blur the surfaces with those materials.
+
+| no denoising | denoised |
+| --------------------------- | ----------------------- |
+| ![](img/sharp.png)     | ![](img/blur.png)   |
+
+For similar reasons, when the lighting condition isn't very even, the image result will also suffer.
+
+| 10 iterations, even lighting condition | 10 iterations, not so even lighting condition |
+| ----------------------- | --------------- |
+| ![](img/denoised.png) | ![](img/cornell-denoised.png) |
+
+## G-Buffer Optimization and Performance
+
+To more efficiently store G-buffer information, we use z-depths and oct-encoded normals instead of positions and normals. There seems to be no apparent performance impact for this optimization. The difference seen in the graph is more of a result of performance time variance rather than any meaningful performance difference.
+
+![](img/chart-gbuffer.png)
+
+## Edge-Avoiding A-Trous Wavelet Transform vs Gaussian Blur
+
+Compared to our implementation, Gaussian blur doesn't get rid of noise so much as to smooth out the noise, with the additional downside of blurring the entire image.
+
+| filter size: 65, A-Trous | filter size: 65, Gaussian | reference |
+| --------------------------- | ----------------------- | -- |
+| ![](img/denoised.png)     | ![](img/gaussian.png)   | ![](img/no-denoise.png) |
+
+Performance wise, Gaussian blur is also getting expensive as the filter size increases.
+
+![](img/chart-gaussian.png)
diff --git a/cmake/CUDAComputesList.cmake b/cmake/CUDAComputesList.cmake
@@ -60,6 +60,8 @@ IF(    CUDA_COMPUTE_20
     OR CUDA_COMPUTE_70
     OR CUDA_COMPUTE_72
     OR CUDA_COMPUTE_75
+    OR CUDA_COMPUTE_80
+    OR CUDA_COMPUTE_86
     )
     SET(FALLBACK OFF)
 ELSE()
@@ -70,8 +72,8 @@ LIST(LENGTH COMPUTES_DETECTED_LIST COMPUTES_LEN)
 IF(${COMPUTES_LEN} EQUAL 0 AND ${FALLBACK})
     MESSAGE(STATUS "You can use -DCOMPUTES_DETECTED_LIST=\"AB;XY\" (semicolon separated list of CUDA Compute versions to enable the specified computes")
     MESSAGE(STATUS "Individual compute versions flags are also available under CMake Advance options")
-    LIST(APPEND COMPUTES_DETECTED_LIST "30" "50" "60" "70")
-    MESSAGE(STATUS "No computes detected. Fall back to 30, 50, 60 70")
+    LIST(APPEND COMPUTES_DETECTED_LIST "30" "50" "60" "70" "80")
+    MESSAGE(STATUS "No computes detected. Fall back to 30, 50, 60, 70, 80")
 ENDIF()
 
 LIST(LENGTH COMPUTES_DETECTED_LIST COMPUTES_LEN)
@@ -90,7 +92,7 @@ MACRO(SET_COMPUTE VERSION)
 ENDMACRO(SET_COMPUTE)
 
 # Iterate over compute versions. Create variables and enable computes if needed
-FOREACH(VER 20 30 32 35 37 50 52 53 60 61 62 70 72 75)
+FOREACH(VER 20 30 32 35 37 50 52 53 60 61 62 70 72 75 80 86)
     OPTION(CUDA_COMPUTE_${VER} "CUDA Compute Capability ${VER}" OFF)
     MARK_AS_ADVANCED(CUDA_COMPUTE_${VER})
     IF(${CUDA_COMPUTE_${VER}})

diff --git a/cmake/FindGLFW.cmake b/cmake/FindGLFW.cmake
@@ -20,66 +20,66 @@
 include(FindPackageHandleStandardArgs)
 
 if (WIN32)
-	# Find include files
-	find_path(
-		GLFW_INCLUDE_DIR
-		NAMES GLFW/glfw3.h
-		PATHS
-		$ENV{PROGRAMFILES}/include
-		${GLFW_ROOT_DIR}/include
-		DOC "The directory where GLFW/glfw.h resides")
+  # Find include files
+  find_path(
+    GLFW_INCLUDE_DIR
+    NAMES GLFW/glfw3.h
+    PATHS
+    $ENV{PROGRAMFILES}/include
+    ${GLFW_ROOT_DIR}/include
+    DOC "The directory where GLFW/glfw.h resides")
 
-	# Use glfw3.lib for static library
-	if (GLFW_USE_STATIC_LIBS)
-		set(GLFW_LIBRARY_NAME glfw3)
-	else()
-		set(GLFW_LIBRARY_NAME glfw3dll)
-	endif()
+  # Use glfw3.lib for static library
+  if (GLFW_USE_STATIC_LIBS)
+    set(GLFW_LIBRARY_NAME glfw3)
+  else()
+    set(GLFW_LIBRARY_NAME glfw3dll)
+  endif()
 
-	# Find library files
-	find_library(
-		GLFW_LIBRARY
-		NAMES ${GLFW_LIBRARY_NAME}
-		PATHS
-		$ENV{PROGRAMFILES}/lib
-		${GLFW_ROOT_DIR}/lib)
+  # Find library files
+  find_library(
+    GLFW_LIBRARY
+    NAMES ${GLFW_LIBRARY_NAME}
+    PATHS
+    $ENV{PROGRAMFILES}/lib
+    ${GLFW_ROOT_DIR}/lib)
 
-	unset(GLFW_LIBRARY_NAME)
+  unset(GLFW_LIBRARY_NAME)
 else()
-	# Find include files
-	find_path(
-		GLFW_INCLUDE_DIR
-		NAMES GLFW/glfw.h
-		PATHS
-		/usr/include
-		/usr/local/include
-		/sw/include
-		/opt/local/include
-		DOC "The directory where GL/glfw.h resides")
+  # Find include files
+  find_path(
+    GLFW_INCLUDE_DIR
+    NAMES GLFW/glfw.h
+    PATHS
+    /usr/include
+    /usr/local/include
+    /sw/include
+    /opt/local/include
+    DOC "The directory where GL/glfw.h resides")
 
-	# Find library files
-	# Try to use static libraries
-	find_library(
-		GLFW_LIBRARY
-		NAMES glfw3
-		PATHS
-		/usr/lib64
-		/usr/lib
-		/usr/local/lib64
-		/usr/local/lib
-		/sw/lib
-		/opt/local/lib
-		${GLFW_ROOT_DIR}/lib
-		DOC "The GLFW library")
+  # Find library files
+  # Try to use static libraries
+  find_library(
+    GLFW_LIBRARY
+    NAMES glfw3
+    PATHS
+    /usr/lib64
+    /usr/lib
+    /usr/local/lib64
+    /usr/local/lib
+    /sw/lib
+    /opt/local/lib
+    ${GLFW_ROOT_DIR}/lib
+    DOC "The GLFW library")
 endif()
 
 # Handle REQUIRD argument, define *_FOUND variable
 find_package_handle_standard_args(GLFW DEFAULT_MSG GLFW_INCLUDE_DIR GLFW_LIBRARY)
 
 # Define GLFW_LIBRARIES and GLFW_INCLUDE_DIRS
 if (GLFW_FOUND)
-	set(GLFW_LIBRARIES ${OPENGL_LIBRARIES} ${GLFW_LIBRARY})
-	set(GLFW_INCLUDE_DIRS ${GLFW_INCLUDE_DIR})
+  set(GLFW_LIBRARIES ${OPENGL_LIBRARIES} ${GLFW_LIBRARY})
+  set(GLFW_INCLUDE_DIRS ${GLFW_INCLUDE_DIR})
 endif()
 
 # Hide some variables

diff --git a/cmake/FindGLM.cmake b/cmake/FindGLM.cmake
@@ -2,12 +2,12 @@
 # Find GLM
 #
 # Try to find GLM : OpenGL Mathematics.
-# This module defines 
+# This module defines
 # - GLM_INCLUDE_DIRS
 # - GLM_FOUND
 #
 # The following variables can be set as arguments for the module.
-# - GLM_ROOT_DIR : Root library directory of GLM 
+# - GLM_ROOT_DIR : Root library directory of GLM
 #
 # References:
 # - https://github.com/Groovounet/glm/blob/master/util/FindGLM.cmake
@@ -18,34 +18,34 @@
 include(FindPackageHandleStandardArgs)
 
 if (WIN32)
-	# Find include files
-	find_path(
-		GLM_INCLUDE_DIR
-		NAMES glm/glm.hpp
-		PATHS
-		$ENV{PROGRAMFILES}/include
-		${GLM_ROOT_DIR}/include
-		DOC "The directory where glm/glm.hpp resides")
+  # Find include files
+  find_path(
+    GLM_INCLUDE_DIR
+    NAMES glm/glm.hpp
+    PATHS
+    $ENV{PROGRAMFILES}/include
+    ${GLM_ROOT_DIR}/include
+    DOC "The directory where glm/glm.hpp resides")
 else()
-	# Find include files
-	find_path(
-		GLM_INCLUDE_DIR
-		NAMES glm/glm.hpp
-		PATHS
-		/usr/include
-		/usr/local/include
-		/sw/include
-		/opt/local/include
-		${GLM_ROOT_DIR}/include
-		DOC "The directory where glm/glm.hpp resides")
+  # Find include files
+  find_path(
+    GLM_INCLUDE_DIR
+    NAMES glm/glm.hpp
+    PATHS
+    /usr/include
+    /usr/local/include
+    /sw/include
+    /opt/local/include
+    ${GLM_ROOT_DIR}/include
+    DOC "The directory where glm/glm.hpp resides")
 endif()
 
 # Handle REQUIRD argument, define *_FOUND variable
 find_package_handle_standard_args(GLM DEFAULT_MSG GLM_INCLUDE_DIR)
 
 # Define GLM_INCLUDE_DIRS
 if (GLM_FOUND)
-	set(GLM_INCLUDE_DIRS ${GLM_INCLUDE_DIR})
+  set(GLM_INCLUDE_DIRS ${GLM_INCLUDE_DIR})
 endif()
 
 # Hide some variables

diff --git a/external/include/GL/Copying.txt b/external/include/GL/Copying.txt