Hey guys, I'm looking at creating a normal mapped gun model for use in a first person shooter. I'm building this gun specifically to be used in the Source engine and I'd like the final version to include a diffuse, normal and specular map.
I'm hoping I can get a few opinions on the best way to create the normal maps for the weapon. The two ways I know of creating normal maps are to model a high poly mesh and project it's normals data onto a low-res base mesh to generate a normal map. Or to use an application which generates the normal map from a greyscale image, usually a modified version of the objects diffuse map. For that type of normals generation I've used Nvidia's Photoshop Normal Map Filter
I know that the later method doesn't produce results as good as a 3d rendered projection off a high-res mesh. And you can also run into problems with upside down UV chunks in your texture sheet needing flipping and re-rendering.
I'm mainly wondering if it's worth the trouble of sub-d modeling a high-res mesh for the gun, as well as the low res mesh. Will the end result be worth all the extra effort, or should I just stick with the Photoshop filter method? Especially for a fairly inorganic object like this. At the moment I'm thinking I'll just use the 2d filter method, but I'd be very interested to hear anyone else's opinions and experiences.
Just to give you an idea of what I'll be making, the gun will be something like this in terms of real world scale, detail and the variety of shapes in its form. Thanks.