#ifdef GL_ES
  precision mediump float;
  #endif
  
  varying vec4 v_fragmentColor;
  varying vec2 v_texCoord;
  
  uniform sampler2D u_maskTexture;
  
  void main() {
      gl_FragColor = v_fragmentColor * texture2D(CC_Texture0, v_texCoord);
      gl_FragColor.w = texture2D(u_maskTexture, v_texCoord).r;
  }