DT228/DT211/DT282/DT508 Games Engines 1 2020-2021

Resources

This is a screenshot of the first part of what you guys can make today:

And this is a video of part two, which involves modifying a shader to generate the colours:

First make sure your fork is updated so you get the latest branches from the upstream.
Switch to the lab1starter branch:

git checkout lab1starter

Open the scene trigscene and check out the hierarchy and the position and orientation of the camera & the generator.
Add a new script to the Generator gameobject called Generator
Add public fields for rings - the number of rings to create and for the prefab to use.
Drag the prefab from the project onto the field in the Unity editor
Now here is the challenge! Write code in the Start method to instantiate instances of the prefab in rings, centred at 0,0,0 on the X-Y plane This will be a nested for loop. But I suggest you try and create one ring first (in a loop) and then enclose that loop in an outer loop to create multiple rings.
You will see that the inside ring had 5 objects and the subsequent rings increase the number of objects so that the spacing on each ring is equal. You can use the circumference of a circle equation to calculate the number of objects each circle should contain.
Add a script to the prefab so that it rotates around the Y axis. You should add a field for the rotation speed.
See if you can figure out how set colours on each loop so that the colours span the hue colour space from 0-1

Create a material called ColorMaterial and assign the shader Custom/ColorShader to the material.
Assign the material to the prefab by dropping it on the prefab.
Open up the file ColorShader.shader and look for the function void surf (Input IN, inout SurfaceOutputStandard o)
You should assign the variable hue to a value between 0 and 1 based on the distance of the vertex from the origin.
You have some input variables to work with which are: IN.worldPos.x and IN.worldPos.y (the vertex x and y) and some functions you can use sqrt, pow, abs. And the modulus operator %
You can also use the built in variable _Time that gives the time in seconds since the program started. It's a float.
If all goes well, you should be able to create the effect in the video.