Trail Particle Refinement

I have finished the basic step of refining the missile trail particle. Originally the trail particle clamp 1 texture, which causes stretch. The stretch effects the control over the trail image. For example, when the missile fly fast and the trail is long, the image get over stretched.
So I changed it to use repeat texturing, and separated the trail into 2 parts: the head and the trail. The head just use half of the texture image with no repeat, so it has a specific shape. The trail use the other half of the image, and use repeat texturing to cover the rest of the trail particle.
The screen shot is the current result, but further refinement and testing is needed. Most likely on the texture needs to be changed.