// Copyright (c) 2017-2020 Xiamen Yaji Software Co., Ltd.

CCEffect %{
  techniques:
  - passes:
    - vert: lighting-vs
      frag: lighting-fs
      pass: deferred-lighting
      rasterizerState:
        cullMode: none
      depthStencilState:
        depthTest: false
        depthWrite: false
}%

CCProgram lighting-vs %{
  precision highp float;
  #include <legacy/decode>
  #include <builtin/uniforms/cc-global>
  #include <common/common-define>

  out vec2 v_uv;

  void main () {
    vec4 position;
    CCDecode(position);
    CC_HANDLE_GET_CLIP_FLIP(position.xy);
    gl_Position = vec4(position.x, position.y, 1.0, 1.0);
    v_uv = a_texCoord;
  }
}%

CCProgram lighting-fs-tiled %{
  precision highp float;
  #include <builtin/uniforms/cc-global>
  #include <legacy/shading-standard-base>
  #include <legacy/shading-standard-additive>
#if CC_ENABLE_CLUSTERED_LIGHT_CULLING == 1
  #include <legacy/shading-cluster-additive>
#endif
  #include <legacy/output-standard>
  #include <legacy/fog-base>
  #include <common/math/octahedron-transform>
  #include <common/math/coordinates>
  #include <common/common-define>

  #pragma subpass
  #pragma subpassColor in albedoMap
  #pragma subpassColor in normalMap
  #pragma subpassColor in emissiveMap
  #pragma subpassDepth in depthStencil

  layout(location = 0) out vec4 fragColor;

  vec4 screen2WS(vec3 coord) {
    vec3 ndc = vec3(
  	  2.0 * (coord.x - cc_viewPort.x) / cc_viewPort.z - 1.0,
      2.0 * (coord.y - cc_viewPort.y) / cc_viewPort.w - 1.0,
      #if __VERSION__ >= 450
      coord.z);
      #else
      2.0 * coord.z - 1.0);
      #endif


    CC_HANDLE_SAMPLE_NDC_FLIP_STATIC(ndc.y);
    return GetWorldPosFromNDCPosRH(ndc, cc_matProj, cc_matViewProjInv);
  }

  void main () {
    StandardSurface s;

    vec4 albedo = subpassLoad(albedoMap);
    vec4 normal = subpassLoad(normalMap);
    vec4 emissive = subpassLoad(emissiveMap);
    float depth = subpassLoad(depthStencil).x;

    s.albedo = albedo;
    vec3 position = screen2WS(vec3(gl_FragCoord.xy, depth)).xyz;
    s.position = position;
    s.roughness = normal.z;
    s.normal = oct_to_float32x3(normal.xy);
    s.specularIntensity = 0.5;
    s.metallic = normal.w;
    s.emissive = emissive.xyz;
    s.occlusion = emissive.w;
#if CC_RECEIVE_SHADOW
    s.shadowBias = vec2(0, 0);
#endif
    // fixme: default value is 0, and give black result
    float fogFactor;
    CC_TRANSFER_FOG_BASE(vec4(position, 1), fogFactor);

    vec4 shadowPos;
    CC_TRANSFER_SHADOW_BASE(vec4(position, 1), shadowPos);

    vec4 color = CCStandardShadingBase(s, shadowPos) +
#if CC_ENABLE_CLUSTERED_LIGHT_CULLING == 1
                 CCClusterShadingAdditive(s, shadowPos);
#else
                 CCStandardShadingAdditive(s, shadowPos);
#endif
    CC_APPLY_FOG_BASE(color, fogFactor);
    color = CCFragOutput(color);

#if CC_USE_DEBUG_VIEW == CC_SURFACES_DEBUG_VIEW_SINGLE
    color = vec4(albedoMap.rgb, 1.0);
#endif

    fragColor = color;
  }
}%

CCProgram lighting-fs %{
  precision highp float;
  #include <builtin/uniforms/cc-global>
  #include <legacy/shading-standard-base>
  #include <legacy/shading-standard-additive>
#if CC_ENABLE_CLUSTERED_LIGHT_CULLING == 1
  #include <legacy/shading-cluster-additive>
#endif
  #include <legacy/output-standard>
  #include <legacy/fog-base>
  #include <common/math/octahedron-transform>
  #include <common/math/coordinates>
  #include <common/common-define>

  in vec2 v_uv;
  #pragma rate albedoMap pass
  layout(binding = 0) uniform sampler2D albedoMap;
  #pragma rate normalMap pass
  layout(binding = 1) uniform sampler2D normalMap;
  #pragma rate emissiveMap pass
  layout(binding = 2) uniform sampler2D emissiveMap;
  #pragma rate depthStencil pass
  layout(binding = 3) uniform sampler2D depthStencil;

  layout(location = 0) out vec4 fragColor;

  vec4 screen2WS(vec3 coord) {
    vec3 ndc = vec3(
  	  2.0 * (coord.x - cc_viewPort.x) / cc_viewPort.z - 1.0,
      2.0 * (coord.y - cc_viewPort.y) / cc_viewPort.w - 1.0,
      #if __VERSION__ >= 450
      coord.z);
      #else
      2.0 * coord.z - 1.0);
      #endif

    CC_HANDLE_SAMPLE_NDC_FLIP_STATIC(ndc.y);
    return GetWorldPosFromNDCPosRH(ndc, cc_matProj, cc_matViewProjInv);
  }

  void main () {
    StandardSurface s;

    vec4 albedo = texture(albedoMap, v_uv);
    vec4 normal = texture(normalMap, v_uv);
    vec4 emissive = texture(emissiveMap, v_uv);
    float depth = texture(depthStencil, v_uv).x;

    s.albedo = albedo;
    vec3 position = screen2WS(vec3(gl_FragCoord.xy, depth)).xyz;
    s.position = position;
    s.roughness = normal.z;
    s.normal = oct_to_float32x3(normal.xy);
    s.specularIntensity = 0.5;
    s.metallic = normal.w;
    s.emissive = emissive.xyz;
    s.occlusion = emissive.w;
#if CC_RECEIVE_SHADOW
    s.shadowBias = vec2(0, 0);
#endif
    // fixme: default value is 0, and give black result
    float fogFactor;
    CC_TRANSFER_FOG_BASE(vec4(position, 1), fogFactor);

    vec4 shadowPos;
    CC_TRANSFER_SHADOW_BASE(vec4(position, 1), shadowPos);

    vec4 color = CCStandardShadingBase(s, shadowPos) +
#if CC_ENABLE_CLUSTERED_LIGHT_CULLING == 1
                 CCClusterShadingAdditive(s, shadowPos);
#else
                 CCStandardShadingAdditive(s, shadowPos);
#endif
    CC_APPLY_FOG_BASE(color, fogFactor);
    color = CCFragOutput(color);

#if CC_USE_DEBUG_VIEW == CC_SURFACES_DEBUG_VIEW_SINGLE
    color = vec4(albedoMap.rgb, 1.0);
#endif

    fragColor = color;
  }
}%