layout (location = 0) in vec3 a_position;
layout (location = 1) in vec3 a_normalAndAnimateOrZ;
layout (location = 2) in vec4 a_texCoords;
layout (location = 3) in vec4 a_color;

layout (location = 0) out vec4 v_texCoords;
layout (location = 1) out vec4 v_maskColor;

layout (binding = 0) uniform UBO
{
  mat4 u_modelView;
  mat4 u_projection;
  mat4 u_pivotTransform;
  vec2 u_contrastGamma;
  float u_opacity;
  float u_zScale;
  float u_interpolation;
  float u_isOutlinePass;
};

void main()
{
  vec2 normal = a_normalAndAnimateOrZ.xy;
  if (a_normalAndAnimateOrZ.z > 0.0)
    normal = u_interpolation * normal;
  vec4 pivot = vec4(a_position, 1.0) * u_modelView;
  vec4 offset = vec4(normal, 0.0, 0.0) * u_projection;
  vec4 projectedPivot = pivot * u_projection;
  gl_Position = applyBillboardPivotTransform(projectedPivot, u_pivotTransform, 0.0, offset.xy);
  float newZ = projectedPivot.y / projectedPivot.w * 0.5 + 0.5;
  gl_Position.z = abs(a_normalAndAnimateOrZ.z) * newZ  + (1.0 - abs(a_normalAndAnimateOrZ.z)) * gl_Position.z;
  v_texCoords = a_texCoords;
  v_maskColor = a_color;
}