// Copyright (c) 2017-2020 Xiamen Yaji Software Co., Ltd.
CCEffect %{
  hideInEditor: true
  techniques:
  - name: transparent
    passes:
    - vert: terrain-brush-vs:vert
      frag: terrain-brush-fs:frag
      depthStencilState:
        depthTest: true
        depthWrite: false
      blendState:
        targets:
        - blend: true
          blendSrc: src_alpha
          blendDst: one_minus_src_alpha
          blendDstAlpha: one_minus_src_alpha
      properties:
        BrushDepthOffset: { value: 0.05 }
}%

CCProgram terrain-brush-vs %{
  precision mediump float;
  #include <builtin/uniforms/cc-global>
  #include <builtin/uniforms/cc-local>

  in vec3 a_position;

  uniform Constant {
    float BrushDepthOffset;
  };

  vec4 vert () {
    vec3 worldPos;
    worldPos.x = cc_matWorld[3][0] + a_position.x;
    worldPos.y = cc_matWorld[3][1] + a_position.y;
    worldPos.z = cc_matWorld[3][2] + a_position.z;
    worldPos.y += BrushDepthOffset; // depth increment for terrain brushes

    vec4 pos = vec4(worldPos, 1);
    pos = cc_matViewProj * pos;

    return pos;
  }
}%

CCProgram terrain-brush-fs %{
  precision mediump float;
  #include <legacy/output>

  vec4 frag () {
    vec4 color = vec4(0.0, 0.0, 0.0, 0.0);
    color.rgb = vec3(100, 100, 135) / 255.0;
    color.a = 0.5;

    return CCFragOutput(color);
  }
}%