Shader "GYGame/CCS/AddTexture"
{
    Properties
    {
        [MainTexture] _MainTex ("主贴图", 2D) = "white" {}
        [HideInInspector] _AdditionalTex ("附加贴图", 2D) = "black" {}
        [HideInInspector] _Rotation ("旋转", Float) = 0
        [HideInInspector] _Color ("颜色", Color) = (1,1,1,1)
        [HideInInspector] _MaskTex ("遮罩", 2D) = "white" {}
        [HideInInspector] _IsNormalTex ("是否为法线贴图", Float) = 0
    }
    
    SubShader
    {
        Tags { 
            "RenderType"="Opaque"
            "RenderPipeline"="UniversalPipeline"
        }
        LOD 100
        
        Pass // index 0
        {
            HLSLPROGRAM
            #pragma vertex vert
            #pragma fragment frag
    
            #include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Core.hlsl"

            TEXTURE2D(_MainTex); SAMPLER(sampler_MainTex);
            TEXTURE2D(_AdditionalTex); SAMPLER(sampler_linear_clamp_AdditionalTex);
            TEXTURE2D(_MaskTex); SAMPLER(sampler_linear_clamp_MaskTex);

            CBUFFER_START(UnityPerMaterial)
            float4 _AdditionalTex_ST;
            float4 _MaskTex_ST;
            float _Rotation;
            half4 _Color;
            float _IsNormalTex;
            CBUFFER_END
            
            struct appdata
            {
                float4 vertex : POSITION;
                float2 uv : TEXCOORD0;
            };

            struct v2f
            {
                float2 uv : TEXCOORD0;
                float4 vertex : SV_POSITION;
            };

            float2 Rotate2D(float2 UV, float Rotation = 0, float2 Center = float2(0.5, 0.5))
	        {
		        Rotation = Rotation/360*2*PI;
	            UV -= Center;
	            float s = sin(Rotation);
	            float c = cos(Rotation);
	            float2x2 rMatrix = float2x2(c, -s, s, c);
	            rMatrix *= 0.5;
	            rMatrix += 0.5;
	            rMatrix = rMatrix * 2 - 1;
	            UV.xy = mul(UV.xy, rMatrix);
	            UV += Center;
	            return UV;
	        }
            
            v2f vert(appdata v)
            {
                v2f o;
                o.vertex = TransformObjectToHClip(v.vertex.xyz);
                o.uv = v.uv;
                return o;
            }

            half4 frag(v2f i) : SV_Target
            {
                //
                float2 uv = Rotate2D((i.uv-_AdditionalTex_ST.zw-0.5)*(1/_AdditionalTex_ST.xy)+0.5, _Rotation);
                float4 additionalColor = SAMPLE_TEXTURE2D(_AdditionalTex, sampler_linear_clamp_AdditionalTex, uv);
                float4 maskColor = SAMPLE_TEXTURE2D(_MaskTex, sampler_linear_clamp_MaskTex, uv);
                //
                additionalColor *= _Color;
                additionalColor.a *= maskColor.r;
                //
                float4 mainColor = SAMPLE_TEXTURE2D(_MainTex, sampler_MainTex, i.uv);
                float4 finalColor = float4(0, 0, 0, 0);
                finalColor.rgb = lerp(mainColor.rgb, additionalColor.rgb, additionalColor.a);
                finalColor.a = 1;
		        return finalColor;
            }
            ENDHLSL
        }
    }
}