// Effect Syntax Guide: https://docs.cocos.com/creator/manual/zh/shader/index.html

CCEffect %{
  techniques:
  - name: opaque
    passes:
    - vert: standard-vs # builtin header
      frag: unlit-fs:fragFront
      rasterizerState:
        cullMode: back
      depthStencilState:
        depthTest: true
        depthWrite: false
        stencilTest: true
        stencilFunc: not_equal
        stencilPassOp: replace
        stencilRef: 0x80 # only use the leftmost bit
        stencilReadMask: 0x80
        stencilWriteMask: 0x80
      blendState:
        targets:
        - blend: true
          blendSrc: zero
          blendDst: one
    - vert: standard-vs
      frag: standard-fs
      properties: &props
        mainTexture:              { value: grey, target: albedoMap, editor: { displayName: AlbedoMap } }
        mainColor:                { value: [1.0, 1.0, 1.0, 1.0], target: albedo, linear: true, editor: { displayName: Albedo, type: color } }
        albedoScale:              { value: [1.0, 1.0, 1.0], target: albedoScaleAndCutoff.xyz }
        alphaThreshold:           { value: 0.5, target: albedoScaleAndCutoff.w, editor: { parent: USE_ALPHA_TEST, slide: true, range: [0, 1.0], step: 0.001 } }
        roughness:                { value: 0.8, target: pbrParams.y, editor: { slide: true, range: [0, 1.0], step: 0.001 } }
        metallic:                 { value: 0.6, target: pbrParams.z, editor: { slide: true, range: [0, 1.0], step: 0.001 } }
      rasterizerState:
        cullMode: front
      depthStencilState:
        stencilTest: true
        stencilFunc: equal
        stencilRef: 0x80
        depthFunc: greater
      blendState:
        targets:
        - blend: true
          blendSrc: one
          blendDst: zero
    # - &forward-add
    #   vert: standard-vs
    #   frag: standard-fs
    #   phase: forward-add
    #   propertyIndex: 0
    #   embeddedMacros: { CC_FORWARD_ADD: true }
    #   depthStencilState:
    #     depthFunc: equal
    #     depthTest: true
    #     depthWrite: false
    #   blendState:
    #     targets:
    #     - blend: true
    #       blendSrc: one
    #       blendDst: one
    #       blendSrcAlpha: zero
    #       blendDstAlpha: one
    # - &shadow-caster
    #   vert: shadow-caster-vs
    #   frag: shadow-caster-fs
    #   phase: shadow-caster
    #   propertyIndex: 0
    #   rasterizerState:
    #     cullMode: front
    #   properties:
    #     mainColor:      { value: [1.0, 1.0, 1.0, 1.0], target: albedo, editor: { displayName: Albedo, type: color } }
    #     albedoScale:    { value: [1.0, 1.0, 1.0], target: albedoScaleAndCutoff.xyz }
    #     alphaThreshold: { value: 0.5, target: albedoScaleAndCutoff.w, editor: { parent: USE_ALPHA_TEST } }
    #     mainTexture:    { value: grey, target: albedoMap, editor: { displayName: AlbedoMap } }
}%


CCProgram shared-ubos %{
  uniform Constants {
    vec4 albedo;
    vec4 albedoScaleAndCutoff;
    vec4 pbrParams;
  };
}%

CCProgram macro-remapping %{
  // ui displayed macros
  #pragma define-meta USE_TWOSIDE
  #pragma define-meta USE_VERTEX_COLOR

  #define CC_SURFACES_USE_TWO_SIDED USE_TWOSIDE
  #define CC_SURFACES_USE_VERTEX_COLOR USE_VERTEX_COLOR
}%
CCProgram surface-vertex %{
  #define CC_SURFACES_VERTEX_MODIFY_WORLD_POS
  vec3 SurfacesVertexModifyWorldPos(in SurfacesStandardVertexIntermediate In)
  {
    return In.worldPos;
  }
  
  #define CC_SURFACES_VERTEX_MODIFY_WORLD_NORMAL
  vec3 SurfacesVertexModifyWorldNormal(in SurfacesStandardVertexIntermediate In)
  {
    return In.worldNormal.xyz;
  }
  
  #define CC_SURFACES_VERTEX_MODIFY_UV
  void SurfacesVertexModifyUV(inout SurfacesStandardVertexIntermediate In)
  {
  }
}%


CCProgram surface-fragment %{
  #if USE_ALBEDO_MAP
    uniform sampler2D albedoMap;
    #pragma define-meta ALBEDO_UV options([v_uv, v_uv1])
  #endif

  #if USE_ALPHA_TEST
    #pragma define-meta ALPHA_TEST_CHANNEL options([a, r])
  #endif

  #define CC_SURFACES_FRAGMENT_MODIFY_BASECOLOR_AND_TRANSPARENCY
  vec4 SurfacesFragmentModifyBaseColorAndTransparency()
  {
    vec4 baseColor = albedo;
    
    #if USE_ALBEDO_MAP
      vec4 texColor = texture(albedoMap, ALBEDO_UV);
      texColor.rgb = SRGBToLinear(texColor.rgb);
      baseColor *= texColor;
    #endif

    #if USE_ALPHA_TEST
      if (baseColor.ALPHA_TEST_CHANNEL < albedoScaleAndCutoff.w) discard;
    #endif

    baseColor.rgb *= albedoScaleAndCutoff.xyz;
    return baseColor;
  }

  #define CC_SURFACES_FRAGMENT_ALPHA_CLIP_ONLY
  void SurfacesFragmentAlphaClipOnly()
  {
    #if USE_ALPHA_TEST
      float alpha = albedo.ALPHA_TEST_CHANNEL;
      #if USE_VERTEX_COLOR
        alpha *= FSInput_vertexColor.a;
      #endif
      #if USE_ALBEDO_MAP
        alpha = texture(albedoMap, ALBEDO_UV).ALPHA_TEST_CHANNEL;
      #endif
  
      if (alpha < albedoScaleAndCutoff.w) discard;
    #endif
  }

  #define CC_SURFACES_FRAGMENT_MODIFY_WORLD_NORMAL
  vec3 SurfacesFragmentModifyWorldNormal()
  {
    // 背面法线方向是反的，所以挖洞时需要在这里取反
    return normalize(-FSInput_worldNormal);
  }

  #define CC_SURFACES_FRAGMENT_MODIFY_EMISSIVE
  vec3 SurfacesFragmentModifyEmissive()
  {
    return vec3(0.0, 0.0, 0.0);
  }

  #define CC_SURFACES_FRAGMENT_MODIFY_PBRPARAMS
  vec4 SurfacesFragmentModifyPBRParams()
  {
    // ao, roughness, metallic, specularIntensity
    return vec4(1.0, pbrParams.y, pbrParams.z, 0.5);
  }
}%




CCProgram standard-vs %{
  precision highp float;

  // 1. surface internal macros, for technique usage or remapping some user (material) macros to surface internal macros
  #include <macro-remapping>
  #include <surfaces/effect-macros/common-macros>

  // 2. common include with corresponding shader stage, include before surface functions
  #include <surfaces/includes/common-vs>

  // 3. user surface functions that can use user (effect) parameters (ubo Constants)
  //    see surfaces/default-functions/xxx.chunk
  #include <shared-ubos>
  #include <surface-vertex>

  // 4. surface include with corresponding shader stage and shading-model (optional)
  #include <surfaces/includes/standard-vs>

  // 5. shader entry with corresponding shader stage and technique usage/type
  #include <shading-entries/main-functions/render-to-scene/vs>
}%


CCProgram shadow-caster-vs %{
  precision highp float;
  #include <surfaces/effect-macros/render-to-shadowmap>
  #include <surfaces/includes/common-vs>
  #include <shared-ubos>
  #include <surface-vertex>
  #include <shading-entries/main-functions/render-to-shadowmap/vs>
}%



CCProgram standard-fs %{
  // shading-model : standard
  // lighting-model : standard (isotropy / anisotropy pbr)
  // shader stage : fs
  // technique usage/type : render-to-scene

  precision highp float;
  // 1. surface internal macros, for technique usage or remapping some user (material) macros to surface internal macros
  #include <macro-remapping>
  #include <surfaces/effect-macros/common-macros>

  // 2. common include with corresponding shader stage, include before surface functions
  #include <surfaces/includes/common-fs>

  // 3. user surface functions that can use user (effect) parameters (ubo Constants)
  //    see surfaces/default-functions/xxx.chunk
  #include <shared-ubos>
  #include <surface-fragment>

  // 4. lighting-model (optional)
  #include <lighting-models/includes/standard>

  // 5. surface include with corresponding shader stage and shading-model (optional)
  #include <surfaces/includes/standard-fs>

  // 6. shader entry with corresponding shader stage and technique usage/type
  #include <shading-entries/main-functions/render-to-scene/fs>
}%

CCProgram shadow-caster-fs %{
  precision highp float;
  #include <surfaces/effect-macros/render-to-shadowmap>
  #include <surfaces/includes/common-fs>
  #include <shared-ubos>
  #include <surface-fragment>
  #include <shading-entries/main-functions/render-to-shadowmap/fs>
}%

CCProgram unlit-fs %{
  precision highp float;
  #include <legacy/output>

  vec4 fragFront() {
    return vec4(1.0, 0.0, 1.0, 1.0);
  }
}%