A downloadable project

Hey! My name is Van Andrew.

During uni break I decided to learn the basics of GLSL using Shadertoy. This page documents some notable projects and what I learnt from each of them.

I've learnt techniques most notably of generating noise, drawing simple shapes and ray marching. In combining these techniques I can procedurally model shapes using SDF's and manipulate them in simple ways using said shapes and noise, as opposed to traditionally modelling them by hand.

You can click on the images below to see the source code!

Or just visit my github.

Showcase

I wanted to learn ray-tracing techniques, and followed a blog from demofox to implement this basic path-tracer. Interesting to see the different implementations of ray-sphere intersection calculation, and sampling theory.

Really happy with this one. I showcase eight different material shaders. Pawn themselves are torus, cylinder and sphere SDF's. From left to right: brushed metal, clay, acrylic, glass, plastic, metal, wax, rock. Shader takes multiple bounces between pawns but NOT with lights so far.

This was an experiment to render clouds, but I ended up with a wax-like material. Used fixed step marching for the interior to calculate light absorption. Looks neat.
New additions from the attempt below: AO, Soft Shadows, SSS, Gerstner Waves, Caustics, Camera Geom. Overall a much closer representation of water from ray marching standpoint.

Following a blog post on rendering water, I attempted to follow along again. This time I managed to get closer to the end product, although I'm missing water caustics. The sand also remains 'dry' and unreactive, which is a problem. However as you'll see below, it is a big improvement. Process video here.
I wanted to play with gradient noise to create ripples as you'd see in the desert. Also playing with post-processing effects makes the scene much more dramatic.

Used perlin noise to generate canyon structures. Played with colouring the rock and adding 'random' patches and shelves. Water actually reflects the sky, instead of approximating it.
Took me a long, long time to finally figure out how to render volumetric clouds. They aren't perfect and run slow, but get the job done. Uses 3D noise applied to a fixed step ray marcher. Doesn't take into account lighting though.

Fur hypertexture using noise texture. Hypertexture extrudes SDF in raymrach function.

This was an attempt to render water from a close-up town down perspective. So of course I had to throw in a sunset for those specular reflections. The buoy here is mainly to showcase the reflections in the water. It also bobs and rotates along with the water. Water surface SDF uses Perlin Noise FBM.

I wanted to redo my waves shader, since perlin noise makes it look more rough and not realistic. This is a modification which uses gerstner waves (borrowed from another shader) and updates the look on the life bouy using polar coordinates. Everything else is identical.

Played around with voronoi-textures as the basis for heightmaps with ray-marching.
Played with a 3D implementation of truchet tiling. Used polar coords to play with texturing and depth.

I am showcasing a variety of different materials here; the wax bust uses sub-surface scattering to create a translucent tone, the glass plate refracts the texture of the wooden table below. Fun to play with textures and for the first time; the phong lighting model.

I played with refraction and reflection with five different spheres of varying density and roughness. Interesting to see the results.

I used fbm and smooth noise to generate organic mountains. Ray marching provides nice lighting. Has a lot of issues with artefacts and distortion.
I went back and redid my previous shader. This one is properly lit (no fake lighting) and much faster with less artefacts.
I went back and redid my terrain shader for the 3rd time. This time I used a texture to create ridges and lit it using 2 lights. Much prettier image. Process video here.
Fourth attempt ray marching mountains. This time I've patched up the colouring method and detail of terrain. Added water using refraction/reflection model from previous shaders.
Iteration 5 of the mountain render. New tricks: volumetric fog (still need to work on blending it better. Also runs really slow. Could apply more noise to fog surface.
I rendered a planet using the same techniques on my previous mountain iterations. I think the revised water looks much better than my first attempt below.
Some cool new tricks: Volumetric rendering, proper coordinate system, triplaner texturing, stars and atmospheric effects.
I wanted to create a quick toon shader. This is using my new template shader code which supports materials. The toon shader just splits up lighting into four (can be changed) bands, which alter the colour output.
I added soft shadows and ambient occlusion to my boilerplate ray marching code. I think it looks pretty neat.
I tried to render clouds but never got to applying 3D noise. This render uses fixed marching steps as opposed to traditional ray marchers. Resultant look gives a nice opaque material.
I played too much Noita and wanted to make a falling sand simulation. Uses buffers to keep track of a pixel's previous state, since shaders enact per frame.
This is a version of Conway's Game of Life which uses cellular automata to create emergent behaviours. I've added a visual changed where pixels leave a 'trail' of where they have been which fades over time, much like slime. I've added CRT effects to add that retro feel.
First time attempting to ray march water and was met with a bunch of issues. This was as far as I could get -basic refraction.