title: Lighting up object on mouse over
body: <p>I'm trying to highlight meshes (animated characters etc) in my game on a mouse-over event.
  They have multiple textures and sometimes skin.</p>
  
  <p>I thought I would wrap them into a ShaderMaterial and on hit-test change uniforms to brighten it up with a fragment shader.</p>
  
  <p>To do this, can I somehow just manipulate the regular shading?
  Can I mix multiple materials, making my shader take color values from the standard shader and just tweak them?
  Or do I need whole separate render pass and blend it with composer?</p>
  
  <p>Or maybe just something else entirely, like ambient light applied to just one object/shader?</p>
  
  <p>Thanks for any suggestions.</p>