Gerstner Wave

-
I remember a Water Shader that Ryan Bruck's made using 'Gerstner Wave'. Initially, I didn't know what Gerstner Wave was but then I looked at Nvidia's GPU Gems book: https://developer.nvidia.com/gpugems/GPUGems/gpugems_ch01.html. It tells you exactly what it does and why it is important. It gives convincing and procedural looking Waves for water that is being used in the Games and Films industry. The equations/formula's for creating this looked scary and very confusing. It made me question if Ryan Bruck's used the material editor or HLSL to make the water.

Ryan Bruck's Water Shader:




I later found that there is a Livestream/tutorial by Dokipen that helps with figuring out how the Gerstner wave is made in the Material Editor. I will go through and see what I come up with.

UE4 Gerstner Wave Livestream/tutorial by Dokipen:


Comments

Post a Comment

Popular posts from this blog

Environment Showcase Concepts

-
Image
I thought it's about time to start working on creating the environment to showcase the water in the best way possible. It was suggested that I create this really cool Skull Waterfall environment concept art by Andrey Egorov: However, I will be using this concept as my initial inspiration and will be making my own iteration to the environment so it will not look exactly the same as the concept. It takes a bit of time figuring out and creating some of the features for the water shader. While I do this, I can work on creating the environment so I will be working on the water shader in small increments.
Read more

Distance Field water foam

-
Image
Distance Field Foam Vectortoradialvalue, DistanceFieldGradient used for U channel and DistanceToNearestSurface used for V. I thought about how texture coordinates worked and how VectorToRadialValue worked. Both being gradients in R(U) and G(V), I had a theory about creating coordinates based on using Distancetonearestsurface node as G(V) channel and have VectorToRadialValue or Distancefieldgradient node as the R(U) channel. I was initially going to use the DistanceFieldGradient node that I learned about when making the distance field flow map. This is because the node had that Texture coordinate look to it but it adds a lot to the shader instructions so I went with VectorToRadialValue node. I extracted and used maths for the R channel from VectorToRadialValue and it produced the coordinates I wanted. I then added this coordinate to the noise based foam I made earlier using Alex Vinogradov's approach. I later decided to add Distancefieldgradient node just to see if it pro
Read more

World alignment (Tri-planar mapping)

-
Image
From reading the UE4 documentation, I found out that material functions are a bunch of nodes packed into one node. I figured out the Math behind how world alignment works by deconstructing and experimenting with the World Aligned Texture node. This node is one example of a material function. It is also widely known as Tri-planar mapping in substance painter. Material Function for Tri-planar mapping  This gave me the idea to make a block out material which can have grids, scale without texture stretching and change colours the way I want it to. I also wanted to add the functionality of animating the material. I did this by making some modifications to the World Aligned Texture material function. Modified Material function with comments to help understand which part is doing what. I found that substracting the WorldPosition from the Object Position will force the material to move along with the object and not have a weird scrolling effect whenever you move the object.
Read more