// Copyright (c) Le Loc Tai <leloctai.com> . All rights reserved. Do not redistribute.

Shader "UI/TranslucentImage"
{
    Properties
    {
        [PerRendererData] _MainTex("Sprite Texture", 2D) = "white" {}

        [Header(Appearance)][Space]
        [KeywordEnum(Normal, Colorful)] _BACKGROUND_MODE("Background Mode", int) = 0

        [Header(Refraction)][Space]
        [KeywordEnum(Off,On,Chromatic)] _REFRACTION_MODE("Refraction Mode", int) = 1
        // Singularity prevent reconstructions of control properties from _RefractiveIndexRatios
        //  so they need to be stored in the material
        [PowerSlider(20)] _RefractiveIndex("Refractive Index", Range(1, 4.5)) = 1.5
        [PowerSlider(2)] _ChromaticDispersion("Chromatic Dispersion", Range(0, 2)) = 0.5
        _RefractiveIndexRatios("Refractive Index Ratio", Vector) = (0.666666, 0.666666, 0.666666, 0)

        [Header(Edge Glint)][Space]
        [Toggle(_USE_EDGE_GLINT)] _USE_EDGE_GLINT("Enable Edge Glint", Float) = 0
        _EdgeGlintDirections("Edge Glint Directions", Vector) = (-0.258819, 0.9659259, 0.2588191, -0.9659258)
        _EdgeGlint1Strength("Edge Glint 1 Strength", Range(0, 1)) = .25
        _EdgeGlint2Strength("Edge Glint 2 Strength", Range(0, 1)) = .1
        _EdgeGlintWrap("Edge Glint Wrap", Float) = 1
        _EdgeGlintSharpness("Edge Glint Sharpness", Float) = 512

        //_Debug("Debug", Vector) = (0,0,0,0)

        [Header(Other)][Space]
        _StencilComp("Stencil Comparison", Float) = 8
        _Stencil("Stencil ID", Float) = 0
        _StencilOp("Stencil Operation", Float) = 0
        _StencilWriteMask("Stencil Write Mask", Float) = 255
        _StencilReadMask("Stencil Read Mask", Float) = 255

        _ColorMask("Color Mask", Float) = 15
        [HideInInspector]_Color ("Dummy Color", Color) = (1,1,1,1)

        [Toggle(UNITY_UI_ALPHACLIP)] _UseUIAlphaClip("Use Alpha Clip", Float) = 0
    }

    SubShader
    {
        Tags
        {
            "Queue"= "Transparent"
            "IgnoreProjector"= "True"
            "RenderType"= "Transparent"
            "PreviewType"= "Plane"
            "CanUseSpriteAtlas"= "True"
        }

        Stencil
        {
            Ref[_Stencil]
            Comp[_StencilComp]
            Pass[_StencilOp]
            ReadMask[_StencilReadMask]
            WriteMask[_StencilWriteMask]
        }

        Cull Off
        Lighting Off
        ZWrite Off
        ZTest[unity_GUIZTestMode]
        Blend One OneMinusSrcAlpha
        ColorMask[_ColorMask]

        Pass
        {
            CGPROGRAM
            // #pragma enable_d3d11_debug_symbols
            #pragma target 3.0
            #pragma exclude_renderers d3d11_9x gles

            #pragma vertex vert
            #pragma fragment frag

            #include "TranslucentImage.hlsl"

            #pragma multi_compile_local _ UNITY_UI_CLIP_RECT
            #pragma multi_compile_local _ UNITY_UI_ALPHACLIP

            #pragma shader_feature_local_fragment _BACKGROUND_MODE_NORMAL _BACKGROUND_MODE_COLORFUL

            half4 frag(VertexOutput IN) : SV_Target
            {
                half2      screenPos;
                half4      foregroundColor;
                Appearance appearance;
                fragSetup(IN, screenPos, foregroundColor, appearance);

                half3 backgroundColor = sampleBackground(screenPos);
                half4 color = blendBackground(foregroundColor, backgroundColor, appearance);

                fragFinish(IN, screenPos, color);

                return color;
            }
            ENDCG
        }
    }

    CustomEditor "LeTai.Asset.TranslucentImage.Editor.TranslucentImageShaderGUI"
}