// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See LICENSE in the project root for license information.

///
/// Basic 3D TextMesh shader with proper z-sorting and culling options.
///
Shader "Mixed Reality Toolkit/Text3DShader"
{
    Properties
    {
        _MainTex("Alpha (A)", 2D) = "white" {}
        [Enum(UnityEngine.Rendering.CullMode)] _Cull("Cull", Float) = 0

        [HideInInspector] _Color("Main Color", Color) = (1,1,1,1)
        [HideInInspector] _StencilComp("Stencil Comparison", Float) = 8
        [HideInInspector] _Stencil("Stencil ID", Float) = 0
        [HideInInspector] _StencilOp("Stencil Operation", Float) = 0
        [HideInInspector] _StencilWriteMask("Stencil Write Mask", Float) = 255
        [HideInInspector] _StencilReadMask("Stencil Read Mask", Float) = 255
        [HideInInspector] _ColorMask("Color Mask", Float) = 15
    }

        SubShader
        {
            LOD 200

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

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

            Cull[_Cull]
            Lighting Off
            ZWrite On
            ZTest[unity_GUIZTestMode]
            Offset -1, -1
            Fog { Mode Off }
            Blend SrcAlpha OneMinusSrcAlpha
            ColorMask[_ColorMask]

            Pass
            {
                CGPROGRAM
                #pragma vertex vert
                #pragma fragment frag
                #pragma multi_compile_instancing
                #include "UnityCG.cginc"

                struct appdata_t
                {
                    float4 vertex : POSITION;
                    half4 color : COLOR;
                    float2 texcoord : TEXCOORD0;
                    UNITY_VERTEX_INPUT_INSTANCE_ID
                };

                struct v2f
                {
                    float4 vertex : POSITION;
                    half4 color : COLOR;
                    float2 texcoord : TEXCOORD0;
                    UNITY_VERTEX_INPUT_INSTANCE_ID
                    UNITY_VERTEX_OUTPUT_STEREO

                };

                sampler2D _MainTex;
                float4 _MainTex_ST;
                UNITY_INSTANCING_BUFFER_START(Props)
                UNITY_DEFINE_INSTANCED_PROP(fixed4, _Color)
    #define _Color_arr Props
                UNITY_INSTANCING_BUFFER_END(Props)

                v2f vert(appdata_t v)
                {
                    v2f o;
                    UNITY_SETUP_INSTANCE_ID(v);
                    UNITY_TRANSFER_INSTANCE_ID(v, o);
                    UNITY_INITIALIZE_VERTEX_OUTPUT_STEREO(o);
                    o.vertex = UnityObjectToClipPos(v.vertex);
                    o.texcoord = TRANSFORM_TEX(v.texcoord, _MainTex);
                    o.color = v.color;
                    #ifdef UNITY_HALF_TEXEL_OFFSET
                        o.vertex.xy += (_ScreenParams.zw - 1.0)*float2(-1,1);
                    #endif
                    return o;
                }

                half4 frag(v2f i) : COLOR
                {
                    UNITY_SETUP_INSTANCE_ID(i);
                    half4 col = i.color;
                    col.a *= tex2D(_MainTex, i.texcoord).a;
                    col = col * UNITY_ACCESS_INSTANCED_PROP(_Color_arr, _Color);
                    clip(col.a - 0.01);
                    return col;
                }
                ENDCG
            }
        }
            CustomEditor "Microsoft.MixedReality.Toolkit.Editor.Text3DShaderGUI"
}