I would like to add smoke to a cannon everytime it fires, does anyone have any pointers on how to do this. I have several methods in mind, but would like input from the blenderheads in the know. I would like to venture down the right pathway first time, so as not to waste time. Any knowledge or expertise you could share would be greatly appreciated…
Thanks…
The NDN…
Use a halo. I could have made you a demo really quick, but all my halo textures were deleted 
My site has some info on how to do halos on the blender page if you get confused trying to do halos.
As for making the smoke cool and stuff, the particle that is the smoke should have a slow upward rise, and you could maybe give it some animation, like rotation and scaling or something. Also, make it an alpha channel and try to animate the alpha values to make it fade out as it rises.
That was my thinking Saluk, am about to start on it, hope to have it done soon… Again thanks for your replies, I say this often, but always mean it, I appreciate you all responding to my questions, makes my learning Blender much easier…
NDNChief…
I did something similar to this once…
maybe a 64*64 square smoke-ish texture on black, textured onto a plane that is facing it’s positive X axis, drawn as a halo (face select [fkey], select in paint buttons), in add mode (also in paint buttons), with collisions turned off, and I think objcolor will need to be turned on. This object will need to be in a layer that is not visible when the game is run. Use an add object acuator to add this object (at the adding object’s center), and give it a long-ish lifespan. You will want to add this object multiple times to make good smoke. If you want the smoke to appear to shoot out of the cannon (in the direction of the cannon ball), and to billow out of the front (upwards) you may have to do some of this twice.
In the ipo window for the object set the colR, colG, colB curves to start at 1.0, and after a time (how fast do you want the ‘smoke’ to clear up), have them go to black. If they are all the same curve the smoke will not change color. In the game buttons make the object play this ipo, and also give it some upward motion. More realisim will be achieved if this object gets larger as it moves upwards, but blender’s implementation of halos makes this more difficult. I don’t want to explain how to here.
The lifespan for the object (set by the add actuator) should be as long or longer than it takes the object color ipo-s to reach black.
I hope that is enough information for now.