code: public Layer setOrigin (float x, float y) {
      this.originX = x;
      this.originY = y;
      this.origin = Origin.FIXED;
      setFlag(Flag.ODIRTY, false);
      return this;
    }
docs: Sets the origin of the layer to a fixed position. This automatically sets the layer's logical
  origin to {@link Origin#FIXED}.
  
  @param x origin on x axis in display units.
  @param y origin on y axis in display units.
  
  @return a reference to this layer for call chaining.