Raymarching-Engine-Unity

A raymarching engine for Unity that supports 25+ primitives and various operations.

2022-02-27.17-08-16.mp4

Rendering a shape

• Append the distance functions in DFs.cginc like

float sdShape(float3 p, // dimension parameters)	
{
    // distance function here
}

• Append the distance function created above in GetDist() in Raymarcher.shader (if using the unlit shader) or in the ImageEffectRaymarcher.shader (if using the Image Effect shader).

float GetDist(Shape shape, float3 p) {
    switch (shape.shapeIndex) {
    case n:
        return sdShape(float3 p, // dimension parameters);
    }
}

• Add the shape in Shape enum and create a struct for its default dimension parameters in RaymarchRenderer.cs

public enum Shape {
    // shape name
};

public struct shapeDimensions
{
   // default shape dimensions;
};

• Make the dimension array in Helpers.cs to be sent as a compute buffer to the Raymarching shader.

public static vector12 GetDimensionVectors(int i)
{
    //dimension array
}

• Finally make a custom editor for your shape in the PropertiesEdior.cs

public override void OnInspectorGUI()
{
    base.OnInspectorGUI();
    EditorGUILayout.Space();
    EditorGUILayout.LabelField("Dimensions", EditorStyles.boldLabel);
    RaymarchRenderer rr = (RaymarchRenderer)target;
    switch ((int)rr.shape)
    {
        //property editor here
    }
}

Implementation for Image Effect Shader

• Attach Raymarcher.cs to the Main Camera and RaymarchRenderer.cs to an empty gameobject and set the properties and type of shape to render in the inspector.
• Drag the ImageEffectRaymarcher.shader in Shader field of Raymarcher.cs in inspector and direction light to the Sun's transform field.

Implementation for Unlit Shader

• Append the following lines in Raymarcher class of Raymarcher.cs

 private void Awake()
 {
     GetComponent<MeshRenderer>().material = _raymarchMaterial;
 }
 private void OnEnable()
 {
     EditorApplication.update += OnUpdate;
 }   
 private void OnUpdate()
 {
     RaymarchRender();
     EditorApplication.QueuePlayerLoopUpdate();
 } 
 private void Update()
 {
     RaymarchRender();
 }
 private void OnDisable()
 {
     EditorApplication.update -= OnUpdate;
     foreach (var buffer in disposable)
     {
         buffer.Dispose();
     }
 }
 
 // Append this in RaymarchRender function
 void RaymarchRender()
 {  
     for (int i = 0; i < renderers.Count; i++)
     {
         if (renderers[i] == GetComponent<RaymarchRenderer>())            
             _raymarchMaterial.SetInt("rank", i);
     }
 }

• Attach RaymarchRenderer.cs and Raymarcher.cs to a gameobject having a mesh renderer and set the properties and type of shape to render in the inspector.
• Drag the Raymarcher.shader in Shader field of Raymarcher.cs in inspector and direction light to the Sun's transform field.