Fractal Raymarcher

explaining the difference between this and my previous material based technique used in the lava lamp:

This first started by wanting to find a way to be able to look through a ray marched object without being constrained by the bounds of the volume, my first method was to conditionally reverse the signed distance function, which I later found would not have worked as it was a misunderstanding of how ray marching works. 

​

Subsequently, I came across the concept of volumetric fog, which inspired me to look into post processing to render ray marched objects. After going through some documentation and following some tutorials, I managed to render a cube with fixed world space coordinates with post processing

​

explaining the rendering:

the script uses the unity camera to align the fractal with the rendered scene;

- the script constructs a frustrum matrix to map the camera's field of view into the shader's world space calculations

- the camera to world matrix passes the transformation matrix from the camera's local space to the world space. 

​

the shader interprets the camera's frustum and position to define how rays are cast and intersect with the fractal geometry​

​

to render:

- the actual rendering is performed in the OnRenderImage method

- the camera renders the scene to a render texture

- the shader processes the render texture to compute the fractal

- a full screen quad applies the processed image back to the frame buffer

​

​

​

​

explaining the menger sponge:

the menger sponge is a recursive fractal structure that starts with a cube, and each step of the recursion, smaller cubes are removed in a specific pattern, creating complex, infinitely detailed structures that resembles a porous sponge. In raymarching, the menger sponge is built by checking the ray's position relative to the sponge's removed regions and adjusting the distance estimator accordingly

​

since its impossible to compute infinite recursion the ray marcher uses a finite number of iterations, the more iterations, the more detail is visible in the sponge, but this increases computational costs