Soft Renderer

This is a Tiny Renderer on CPU built from scratch, using OpenGL-similar API design. this project served as learning project and took quite a lot reference from project https://github.com/zauonlok/renderer for multi-platform depolying.

Features

I intend to implement a shader-based renderer that runs on CPU from scratch using c++ with minimum dependencies, with the following features:

• CPU rasterization
• Shading via shaders
• Similar to OpenGL API
• Cross Platform (MacOS, Windows)
• Image and Geometry Processing

Shader-based pipeline

A simple example for creating a shader, simply inherit class Shader, you are able to access lighting, scene, mvp matrix, interpolated attributes and so on.

#include "src/api.hpp"
using namespace LuGL;

class ExampleShader : public Shader
{
public:
    virtual v2f vert(const vdata in, const Entity * entity, const Scene & scene) const;
    virtual vec4 frag(const v2f in, const Entity * entity, const Scene & scene) const;
};

v2f ExampleShader::vert(const vdata in, const Entity * entity, const Scene & scene) const
{
    v2f out;

    out.position = MVP_MATRIX * vec4(in.position, 1.0f);
    out.texcoord = in.texcoord;
    out.normal   = MODEL_INV_TRANSPOSE * in.normal;

    return out;
}

vec4 ExampleShader::frag(const v2f in, const Entity * entity, const Scene & scene) const
{
    rgb color = rgb(
        in.normal.x * 0.5f + 0.5f,
        in.normal.y * 0.5f + 0.5f,
        in.normal.z * 0.5f + 0.5f );
    
    return vec4(color.normalized(), 1.0f);
}

AntiAliasing

8X MSAA	4X MSAA	2X MSAA	No AA
7 FPS	10 FPS	12 FPS	21 FPS

Switch Shading & Mouse Manipulation

Code Sample in src/sample/demo.cpp

Teapot	Spot

Triangle Normal Shading	Vertex Normal Shading

Todos

• Basic Math Liberary
• Basic Resource IO (.obj, .bmp)
• Basic Rasterization Implementation
• Basic Graphics Pipeline that runs on single thread
• Win32 Application API
• Simple Shaders (Unlit, VertexNormal, TriangleNormal)
• Hovering Camera by Mouse Drag
• Implement Barycentric Triangle Rastrization with Perspective Correction Interpolation
• Wireframe Display
• Multisample anti-aliasing (2X/4X/8X)
• Normal Mapping
• Read .mtl for Material
• Basic Lighting + Phong, Blinn Shaders
• Mipmapping
• Sky Box + Environment Map
• PBR
• PostProcessing Pass
• Shadow
• SSAO
• SS Reflection
• Alpha Test + Alpha Blending
• Multi-threading using openmp

Bug Report

• MacOS screenshot produce error BMP file

Current Features

• basic linear algebra

  • vector
  • quaternion
  • matrix

• IO

  • BMP Format
  • OBJ Format

• Graphics

  • basic rasterization algorithm
  • colormap
  • digit display
  • programable shader
  • MSAA

• Others

  • dynamic array
  • quick sort

Current Platform

MacOS (Cocoa App)

Windows (Win32 App)

Compile & Run

MacOS

• compile

make macos

• run

./viewer

Windows

• compile

mingw32-make win32

• run

viewer