## White Noise

Many of you may know what white noise is and how it can be used in code.
But there are a spectrum of  'Coloured Noises' as well these include ones like brown noise, pink, blue and violet noise all these have slightly different properties and can be very useful in creating different effects. More details on coloured noises can be found HERE.
 Comparison of noiseless and noisy image
A lot of movies as well as video games like City Skylines use white noise to add a feeling of realism and texture to the on screen content, it's also referred to as a grain filter or overlay. It is a really subtle effect and should not be over used.
Creating white noise boils down to the random function used.
While writing C++ code or C# code we have access to good pseudo-random functions from their standard libraries... but while writing code in shaders we usually have to create our own pseudo-random number generator.
One really good way of making one is by using the frac( in Unity & HLSL ) or fract( in GLSL ) function which returns the fractional part of a number.
``````float random( float2 point )
{
return frac(sin(dot(point.xy,float2(someXvalue,someYvalue)))*someFloatWithManyDecimals);
}
``````
Why are we using this 'special arrangement' of functions to make our pseudo-random number generator?
The dot product :- gives values based on how close the directions of  2 vectors are to each other.
The sin function :- gives us value from -1.0 to 1.0 based on the input from the dot product.
The frac function :- gives us the fractional part of the entire thing, which will be our random number.
After tweaking some of these values you should be getting a pretty decent random number generator.
We will be making an effect that looks like this. It's a bit exaggerated for effect.☺.
 An example of grain filter shader
First we will see what the properties of the shader are:
``````Properties
{
_MainTex("Texture", 2D)="white"
_NoiseScale("Noise Scale",Float) = 50.0
_Strength("Noise Strength",Float) = 1.0
}
``````
What are they? :
``````sampler2D _MainTex; //Texture Used
float _NoiseScale; //How big each noise block is
float _Strength; //How prevalent it is in final image
``````
We will look at the random function used ( by me ).
``````float random( float2 p )
{
return frac(sin(dot(p.xy ,float2( _Time.y,6.115)))*53.8856);
}
``````
I have used _Time.y as a parameter to change the noise each frame.
``````fixed4 frag (v2f i) : SV_Target
{
float2 normUV = i.uv;
normUV *= _NoiseScale; // Scale the coordinate system by _NoiseScale amount
float2 ipos = floor(normUV);  // get the integer coords
float rand = random(ipos); // Assign a random value based on the integer coord
fixed4 col = fixed4(rand,rand,rand,1.0);
col = lerp( tex2D(_MainTex,i.uv),col,_Strength ); /*Interpolating between the noise and
texture image by _Strength Value*/
return col;
}
``````
The entire source code of shader is HERE
If you like programming shaders make sure you check these out : Shader Tutorials
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### Gift Wrapping Convex Hull Algorithm With Unity Implementation

Convex Hull Algorithm Convex Hull algorithms are one of those algorithms that keep popping up from time to time in seemingly unrelated fields from big data to image processing to collision detection in physics engines, It seems to be all over the place. Why should you care? Cus you can do magic with it and it seems so simple to implement when you first hear about it, but when you start thinking about it, you will realize why it's not such a straightforward thing to do.
Now that I got you interested (hopefully) and now we will see just what a convex hull is.
As you may have noticed a perimeter was made with the same points that was given and these perimeter points enclose the entire set of points.
Now we have to clear up the term 'Convex'.
Convex means no part of the object is caved inwards or that none of the internal angles made by the points exceed 180 degrees.
In this example of a concave shape internal angles go beyond 180 degrees.
What are those red lines for? Well...…

The process of shader optimization can seem like trial and error... in fact, that's how it is most of the time.
Most of the time shader optimizations could be boiled down to educated guesses because each time a shader gets compiled, the GPU driver of that specific hardware is what converts your code into actual machine code, therefore, the machine code generated will be different for each GPU and the driver itself might perform some optimizations on top of your's which won't be available on another GPU, thereby making it difficult to have a standard way of writing optimal shader code.

So the best way to know for sure is to actually test it on the hardware you are targeting.
With that said, Here are some universal best ways of getting your shader to perform better.😅 Do Calculations On Vertex Shader The most commonly used case for this is lighting, an example would be Gouraud lighting, where lighting calculations are done per vertex but at the loss of quality.

Some calculatio…

### Fortnite Procedural Construction Animation Shader

Fortnite Construction Shader This shader is loosely based on the one that was presented by the Fortnite developers in their GDC talk: Inner Working Of Fortnite's Shader-Based Procedural Animations.

Here is what we will end up with:
This technique requires you to author the 3D model in a certain way, More or less how those Fortnite developers did.
So we need the authored 3D model and the shader that uses data we get from the model to achieve the desired effect.

There are some nuances here and there so make sure you don't miss out on the details.😗
The first step will be preparing the 3D model and putting in the required data. I used Blender 2.79 but any 3D modeling software would do.
3D Model PreparationModel It
Apply Vertex Colors: For the direction of flight
Each color is a component of a vector (x, y, z). This will be considered as local space.
Values range from -1.0 to +1.0 for each component.
Negative values are achieved by using values of less than 0.5 and positive values wi…

### Visual Upgrade - Unity Asset Store [ September, 2018 ]

Visual Overhaul - Assets That Turn Mediocre Into Drool Worthy *Note: These assets are not arranged in any way, no comparison is done. They are just really cool assets that will help make your game look at least a bit better. 😁
8. Bat Particles
7.GPU Instancing Animation
6.Colored Pencils
4.Sleek Render: Mobile Post Processing
3.1000+ Effects pack
2.COLR - Coloring Redefined
1.AllSky

Check out more such Unity Asset Store Gems : HERE
Don't forget to share these wonderful assets with your colleagues and friends.
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