Path Tracing Renderer

Interactive Path Tracing Renderer with an OpenGL backend, written in C.

Current features:

• GUI to control internal rendering parameters
• Support for many GPUs (specifically those without hardware ray tracing support) thanks to the usage of OpenGL 4.6
• Basic support of glTF 2.0
• Move the camera around the scene
• Save rendered image to file
• Two BVH types are available: Midpoint split and a Surface Area Heuristic
• Settings available from CLI

Building

NOTE: Prebuilt binaries for Windows, macOS and Linux can be downloaded from the Releases page.

This project uses submodules for its dependencies, so make sure to get them when cloning.

git clone https://github.com/MaksRawski/PathTracingRenderer --recurse-submodules

If you have cloned without submodules, run this inside the project directory

git submodule update --init --recursive

The only system dependencies on Linux are make, cmake a C compiler and whatever GLFW needs.

On Windows and macOS, cmake and a C compiler should be enough.

Once you have them, you can build the project using either Make (recommended for Linux) or CMake (only option for Windows and macOS).

Make (Linux)

Build dependencies

make -Clib

Build the project

make MODE=release

Run it

./build/release/main

Run tests:

make tests

CMake (Windows)

Configure

cmake -Bbuild -DCMAKE_BUILD_TYPE=Release

Build the project

cmake --build build --config Release

Run it

./build/Release/PathTracingRenderer.exe

Run tests:

cmake -Bbuild -DBUILD_TESTS=ON && cmake --build build --config Debug && ./build/debug/tests.exe

CMake (macOS)

Configure

cmake -Bbuild -DCMAKE_BUILD_TYPE=Release

Build the project

cmake --build build

Run it

./build/PathTracingRenderer

Run tests:

cmake -Bbuild -DBUILD_TESTS=ON && cmake --build build && ./build/tests

Coding conventions

Naming

• snake_case for function_names, variable_names and struct_members

• PascalCase for StructNames

• MACRO_CASE for macros

• StructName_new for "constructors" and StructName_delete for "destructors"

• StructName_function_name for functions that operate on a given struct directly

• function__template for macros that expand into function definitions

• a pair of MACRO_NAME and MACRO_NAME_impl for functions that need __LINE__ and __FILE__

• MACRO_NAME_ for a not to be used directly macro

• g_GLOBAL for global variables

Other

• "private" struct functions/helper functions are static defined within the same translation unit.
• stack allocation is heavily preferred
• functions that "return a string" take a char *buf as argument or return either SmallString (char[1024]) or TinyString (char[16])
• 16MB Arena is allocated at the beginning of main and is passed around for all temporary allocations needs
• only big allocations (theoretically gigabytes) are malloc'ed
• stdint.h types are preferred over int, long etc.