Contrast and hue using CG in Unity

Dears CG developer,

I'm looking for how I could how to adjust contrast or hue of 3D object using CG ?

Thx for any help

 

I did contrast image effect in cg before,
in cg's pixel shader,
adjust contrast:

//custom data
//you can control this in C#
//SetFloat("contrastIntensity", contrastIntensity);
uniform float contrastIntensity;

float4 frag (v2f_img i) : COLOR
{
float4 temp = tex2D(_MainTex,i.uv);
temp = (temp-0.5)*contrastIntensity + 0.5;

return temp;
}

//when contrastIntensity = 1, the result is normal
//when contrastIntensity < 1, the result is less contrast
//when contrastIntensity > 1, the result is more contrast

 

Thank you!
Did u worked on the noise, distortion or chromatic aberrations of the texture? that would be much inetresting for me. Thank you again for your help : ))

 

chromatic aberrations =

Code (CSharp):

1. Shader "C4Cat/Image Effects/Chromatic Aberration" {
2. Properties {
3.     _MainTex ("Base (RGB)", RECT) = "white" {}
4. }
5. SubShader {
6.     Pass {
7.         ZTest Always Cull Off ZWrite Off
8.         Fog { Mode off }
9. CGPROGRAM
10. #pragma vertex vert_img
11. #pragma fragment frag
12. #pragma fragmentoption ARB_precision_hint_fastest
13. #include "UnityCG.cginc"
14. // frag shaders data
15. uniform sampler2D _MainTex;
16.  
17. //custom data
18. uniform float chromaticAberrationIntensity;
19. uniform float vignetteStrength;
20. // frag shader
21. float4 frag (v2f_img i) : COLOR
22. {
23.     float uvOffsetModify = (abs(i.uv.y-0.5) * abs(i.uv.x-0.5));
24.     //float uvOffsetModify = abs(i.uv.y-0.5);          
25.     float2 uvOffset = float2(chromaticAberrationIntensity,0);
26.     uvOffset *= uvOffsetModify;
27.    
28.     //shift R to left a bit
29.     float2 uvR = i.uv - uvOffset;
30.     float4 temp = tex2D(_MainTex, uvR);
31.     float R = temp.r;
32.    
33.     //keep B in original position
34.     temp = tex2D(_MainTex, i.uv);
35.     float B = temp.b;
36.    
37.     //shift G to right a bit
38.     float2 uvG = i.uv + uvOffset;
39.     temp = tex2D(_MainTex, uvG);
40.     float G = temp.g;
41.    
42.     //combine R G B result
43.     float4 result = float4(R,G,B,1);
44.    
45.     result *= 1 - uvOffsetModify * vignetteStrength;
46.    
47.    
48.     return result;
49. }
50. ENDCG
51.     }
52. }
53. Fallback off
54. }

sample R a bit left,
sample G a bit right,
sample B as usually,
combine RGB for output.

 

distortion =
sample pixel color with offset UV,
how each pixel offset when sampling texture is base on your need.

noise, what kind of noise you need?

Are you doing something like a TV shader?

 

In my case it's exactly to copy noise from a texture(I dunno how to do it) and put it my 3D object via the shader.

 

can a simple multiply works for you?
mainTex * noise