uniform sampler2D depthTex;
uniform float alpha = 1.0;
uniform ivec4 dataMask = ivec4(0xFF);

in ivec4 data;
in vec3 pos;
#ifndef FACEDOT
in vec3 vnor;
#else
in vec4 norAndFlag;
#  define vnor norAndFlag.xyz
#endif

out vec4 finalColor;
#ifdef EDGE
out vec4 finalColorOuter;
#endif
#ifdef USE_GEOM_SHADER
out int selectOveride;
#endif

bool test_occlusion()
{
  vec3 ndc = (gl_Position.xyz / gl_Position.w) * 0.5 + 0.5;
  return ndc.z > texture(depthTex, ndc.xy).r;
}

vec3 non_linear_blend_color(vec3 col1, vec3 col2, float fac)
{
  col1 = pow(col1, vec3(1.0 / 2.2));
  col2 = pow(col2, vec3(1.0 / 2.2));
  vec3 col = mix(col1, col2, fac);
  return pow(col, vec3(2.2));
}

void main()
{
  GPU_INTEL_VERTEX_SHADER_WORKAROUND

  vec3 world_pos = point_object_to_world(pos);
  gl_Position = point_world_to_ndc(world_pos);

  ivec4 m_data = data & dataMask;

#if defined(VERT)
  finalColor = EDIT_MESH_vertex_color(m_data.y);
  gl_PointSize = sizeVertex * 2.0;
  /* Make selected and active vertex always on top. */
  if ((data.x & VERT_SELECTED) != 0) {
    gl_Position.z -= 1e-7;
  }
  if ((data.x & VERT_ACTIVE) != 0) {
    gl_Position.z -= 1e-7;
  }

  bool occluded = test_occlusion();

#elif defined(EDGE)
#  ifdef FLAT
  finalColor = EDIT_MESH_edge_color_inner(m_data.y);
  selectOveride = 1;
#  else
  finalColor = EDIT_MESH_edge_vertex_color(m_data.y);
  selectOveride = (m_data.y & EDGE_SELECTED);
#  endif

  float crease = float(m_data.z) / 255.0;
  float bweight = float(m_data.w) / 255.0;
  finalColorOuter = EDIT_MESH_edge_color_outer(m_data.y, m_data.x, crease, bweight);

  bool occluded = false; /* Done in fragment shader */

#elif defined(FACE)
  finalColor = EDIT_MESH_face_color(m_data.x);
  bool occluded = true;

#elif defined(FACEDOT)
  finalColor = EDIT_MESH_facedot_color(norAndFlag.w);

  /* Bias Facedot Z position in clipspace. */
  gl_Position.z -= 0.00035;
  gl_PointSize = sizeFaceDot;

  bool occluded = test_occlusion();

#endif

  finalColor.a *= (occluded) ? alpha : 1.0;

#if !defined(FACE)
  /* Facing based color blend */
  vec3 vpos = point_world_to_view(world_pos);
  vec3 view_normal = normalize(normal_object_to_view(vnor) + 1e-4);
  vec3 view_vec = (ProjectionMatrix[3][3] == 0.0) ? normalize(vpos) : vec3(0.0, 0.0, 1.0);
  float facing = dot(view_vec, view_normal);
  facing = 1.0 - abs(facing) * 0.2;

  /* Do interpolation in a non-linear space to have a better visual result. */
  finalColor.rgb = non_linear_blend_color(colorEditMeshMiddle.rgb, finalColor.rgb, facing);
#endif

#ifdef USE_WORLD_CLIP_PLANES
  world_clip_planes_calc_clip_distance(world_pos);
#endif
}