Hello
Is it possible that I can change the color of a part of a texture with this (Color thing - Album on Imgur) texture? I want the black to be the stuff that get’s changed from the original (Color thing - Album on Imgur scroll down a bit) texture. So I can only color the body part of the vehicle instead of using diffuse which colors the whole car.
If it’s unclear, please tell me and I will explain it more.
It can be done with shader coding. When you use build-in standard shaders you can write your own shaders. in this case you can simple write a surface shader like this and apply the albedo and mask texture:
Shader "Custom/MaskShader"
{
Properties
{
_Color ("Color", Color) = (1,1,1,1)
_MainTex ("Albedo (RGB)", 2D) = "white" {}
_MaskTex("Maks (RGB)", 2D) = "white" {}
_Glossiness ("Smoothness", Range(0,1)) = 0.5
_Metallic ("Metallic", Range(0,1)) = 0.0
}
SubShader
{
Tags { "RenderType"="Opaque" }
LOD 200
CGPROGRAM
// Physically based Standard lighting model, and enable shadows on all light types
#pragma surface surf Standard fullforwardshadows
// Use shader model 3.0 target, to get nicer looking lighting
#pragma target 3.0
sampler2D _MainTex;
sampler2D _MaskTex;
struct Input
{
float2 uv_MainTex;
};
half _Glossiness;
half _Metallic;
fixed4 _Color;
// Add instancing support for this shader. You need to check 'Enable Instancing' on materials that use the shader.
// See https://docs.unity3d.com/Manual/GPUInstancing.html for more information about instancing.
// #pragma instancing_options assumeuniformscaling
UNITY_INSTANCING_BUFFER_START(Props)
// put more per-instance properties here
UNITY_INSTANCING_BUFFER_END(Props)
void surf (Input IN, inout SurfaceOutputStandard o)
{
// Albedo comes from a texture tinted by color
fixed4 c = tex2D(_MainTex, IN.uv_MainTex)*(1-tex2D(_MaskTex, IN.uv_MainTex)) + tex2D (_MainTex, IN.uv_MainTex) * tex2D(_MaskTex, IN.uv_MainTex)*_Color;
o.Albedo = c.rgb;
// Metallic and smoothness come from slider variables
o.Metallic = _Metallic;
o.Smoothness = _Glossiness;
o.Alpha = c.a;
}
ENDCG
}
FallBack "Diffuse"
}

Here are some learningresources:
Unity manual about writing surface shaders
Unitys overview of writing surface and vertex/fragment shaders
If you are using different renderpipelines like URP or HDRP there is a free visual shader programming tool from Unity called ShaderGraph.
Unity Shader Graph introduction
A good tool in current build-in renderpipeline for people with less knowledge on shader programming to understand and learn shaderprogramming might be a visual shader programming tool like Amplify Shader Editor.
are you talking about changing the color in unity or in some art program?