title: Draw particles with Additive but without make transparency against the background in LibGDX
body: <p>I have a typical fire particle effect. (i am not going to show the particle code, the default demo particle at the open of the particle editor works as example).
  I need to check the Additive option to make the particles sum theirs colors to reach the desired effect of fire.
  Later, in my LibGDX game, the fire particle effect draws against a blue sky background. The fire effect do a transparency agains the blue background and the fire seems pink.
  Is nice as magic fire, but i want to draw a normal fire. In black background it seems ok.
  How i can archive a normal fire, without sum their color with the background, but without check the needed Additive option in the particle effect?
  I have test several things, without any result...</p>