VSoftRenderer

VSoftRenderer is my cross-platform 3D toy soft renderer.

VSoftRenderer is still under development...

Showcases:

• Gouraud Shading
• Phong Shading with Diffuse + Normal + Specular Textures

Features

• Cross Platform (Windows, Linux, macOS)
• Light-weight Implementation
• Programmable Shading Pipeline

  • Define a shader through C++:

    struct PhongShader : public VGLShaderBase
    {
        int BindDiffuseTextureSlot;
        int BindNormalTextureSlot;
        int BindSpecularTextureSlot;
    
        Vector3Float UniformLightDirection;
        Matrix4      UniformMVP;
        Matrix4      UniformMVPIT;
    
        std::vector<Vector2Float> VaryingUVs {3};
    
        virtual void vert(int faceIndex, int vertexIndexInFace, Vector3Float& gl_Position) override
        {
            VaryingUVs[vertexIndexInFace] = TargetMesh->GetUV(faceIndex, vertexIndexInFace);
            gl_Position = UniformMVP * gl_Position;
        }
    
        virtual bool frag(Vector3Float bc, VGL::Color& gl_FragColor) override
        {
            Vector2Float uv = VaryingUVs[0] * bc.X + VaryingUVs[1] * bc.Y + VaryingUVs[2] * bc.Z;
            Vector3Float n = (UniformMVPIT * sample2D(BindNormalTextureSlot, uv.X, uv.Y).XYZ()).Normalized();
            Vector3Float l = (UniformMVP * UniformLightDirection).Normalized();
            Vector3Float r = (n*(n*l*2.f) - l).Normalized();
            float diffuseIntensity = std::max(0.0f, n * l);
            Color diffuseColor = sample2D(BindDiffuseTextureSlot, uv.X, uv.Y);
            float specularIntensity = std::pow(std::max(0.0f, r.Z), sample2D(BindSpecularTextureSlot, uv.X, uv.Y).R / 1.0f);
            gl_FragColor = (diffuseColor * (diffuseIntensity + 0.4f * specularIntensity)).Clamped().IgnoreAlpha();
            return false;
        }
    };

  • Use OpenGL-like APIs:

    // ... load meshes & textures from disk
    
    glViewPort(0, 0, 800, 800);
      
    glClearColor({50, 50, 50, 255});
    glClear();
      
    DirectionalLight light(Vector3Float(1, 1, 1).Normalized());
    
    // Camera parameters
    Vector3Float eye(1 , 1, 3);
    Vector3Float center(0 , 0, 0);
    Vector3Float up(0 , 1, 0);
    
    Matrix4 modelMatrix = Matrix4::Identity();
    Matrix4 viewMatrix = glLookAt(eye, center, up);
    Matrix4 projectionMatrix = glProjection(eye, center);
    
    Matrix4 mvp = projectionMatrix * viewMatrix * modelMatrix;
    
    glBindTexture(0, diffuseTexture);
    glBindTexture(1, normalTexture);
    glBindTexture(2, specularTexture);
    
    PhongShader shader = {};
    shader.UniformMVP = mvp;
    shader.UniformMVPIT = mvp.InverseTranspose();
    shader.UniformLightDirection = light.GetDirection();
    shader.BindDiffuseTextureSlot = 0;
    shader.BindNormalTextureSlot = 1;
    shader.BindSpecularTextureSlot = 2;
    
    glBindShader(0, &shader);
    
    for (int meshIndex = 0; meshIndex < meshes.size(); ++meshIndex)
    {
        glBindMesh(meshIndex, meshes[meshIndex]);
        glUseShaderProgram(0);
        glDrawMeshIndexed(meshIndex);
    }

Prerequisites

To build VSoftRenderer, you must first install the following tools.

Windows 10/11

• Visual Studio 2019 (or above) with C++ Desktop Development Environment
• CMake 3.20 (or above)
• Git 2.1 (or above)

Ubuntu 22.04 or above (Linux or WSL2)

Install prerequisite packages:

sudo apt-get update
sudo apt-get install build-essential cmake git clang libx11-dev libxrandr-dev libxrender-dev libglvnd-dev libxinerama-dev libxcursor-dev libxi-dev libomp-dev

MacOS

• XCode 13 (or above)
• CMake 3.20 (or above)
• Git 2.1 (or above)

Build VSoftRenderer

Clone this repository:

git clone --recursive git@github.com:zzxzzk115/VSoftRenderer.git

Build on Windows

Build it automatically:

Just double-click BuildWindows.bat or you can simply use Jetbrains CLion to debug or release.

Build it manually:

cmake -S . -B build

Then open the generated solution file with Visual Studio.

Build on Linux / WSL2

Build it automatically:

chmod +x *.sh && ./BuildLinux.sh

Build on MacOS

Build it automatically:

chmod +x *.sh && ./BuildMacOS.sh

Build it manually:

cmake -S . -B build -G "Xcode"

Then open the generated project file with XCode.

Acknowledgement

We would like to thank the following projects for their invaluable contribution to our work:

• tinyrenderer
• raylib
• tinyobjloader

License

This project is licensed under the MIT license.