title: OpenGL ES 1.1: How to change texture color without losing luminance?
body: <p>I have particles that I want to be able to change the color of in code, so any color can be used.  So I have only one texture that basically has luminance.</p>
  
  <p>I've been using <code>glColor4f(1f, 0f, 0f, 1f);</code> to apply the color.</p>
  
  <p>Every blendfunc I've tried that has come close to working ends up like the last picture below. I still want to preserve luminance, like in the middle picture. (This is like the Overlay or Soft Light filters in Photoshop, if the color layer was on top of the texture layer.)</p>
  
  <p>Any ideas for how to do this without programmable shaders?  Also, since these are particles, I don't want a black box behind it, I want it to add onto the scene.</p>
  
  <p><img src="https://i.stack.imgur.com/XIXk0.jpg" alt="alt text"></p>