SS, I was not so concerned with 'projection origins' as this seems to be more a point of where the weapons projectile effects align with the weapon, then correct weapon position, perspective, scale, and angle.
This is not a minor cosmetic issues; gesture based aim is an important aspect of having first person weapon models in FPS reticule aim games -- i.e. the reticule is absolute aim but the weapon position is what directs a lot of peoples aiming transitions, when moving, turning, following a target.
It's also important in the sense that it was important enough to put weapon models in the game in the first place; one would think that in a 'First Person Shooter' where the most significant element and implement of world interaction, your weapon, would be 'important'. It was obviously 'important' enough to include an enormous number of weapons in WFF where just one could do the job.
Correct perspective is improtant because of inherently correct 'feel' based on human FPP (first person perspective) makes a game more immersive because the weapons are in correct position, scale and perspective for actually hitting intended targets under your reticle.
In several of the WFF screenshots like this one:
http://www.shadowspawn.net/temp/wfusion220.jpg
... where the weapon positions depicted is grossly incorrect in scale, position, and angle. If you align a pencil with the ray trace of absolute aim (i.e. the reticule) and the ray traced by the weapons barrel you will see the two intersect at a vertix absurdly close to the player.
Some of the WFF weapons like the sniper rifle, depict position, perspective, scale, and angle that are virtually correct. But for the game to maintain correct perspective all weapon perspectives, angles and relative positions should be uniform.
The only game I know of that I can actually present screen shots as examples that has correctly positioned, scaled, and angled weapons is Raven Shield; they put an lot of attention and work into this and it paid off enormously in game feel and the aiming mechanics of the game...
http://www.raven-shield.com/ss/Oil_031.jpg
Do the pencil trace experiment with this picture and it's clear that the actual ballistic trace and absolute aim trace have origins that are much closer and the intersection is at or near a range that the weapon actually hits a target in-game. Of course any separation of the axis of absolute aim and weapon aim creates a vertex which is the only range at which the weapon would actually hit a target under your reticule. But, by minimizing separation, you obscure that distance, and generally the less separation, and weapon angle the more obscure and correct weapon position will be.
An introduction to the concepts of correct perspective and scale can be found here:
http://mathforum.org/sum95/math_and/perspective/perspect.html
Generally in the case of game design; correct weapon scale, angle and positioning involves:
[i] Moving the weapon position as close to the center of the screen as possible, this is where most weapons held by you would actually appear in your real perspective first person perspective, and achieves the most correct scale. The humanoid holding the weapon in 'wfusion220.jpg' would have shoulders approximately eight feet in breadth to should the weapon as depicted.
[ii] The rear aperture sight should not be lower or higher then the foresight or vise versa -- ideally on same plane - for weapon positions to show off weapon detail though 'nose high' is more acceptable if the weapons apparent position is lowered...
[iii] Minimize weapon angle, less is almost always better, short of dead center and an absolute 'ironsights' picture -- but weapon angle should never be greater then 27° or its aim will be dystopic with the reticule.
Of course showing off weapon models is a big part of having them in the game, but fire and reload animations can do a much better job of showing off weapons then grossly angled static fire positions, and as previously mentioned correctly perspected and angled weapons are important to game feel in terms of correct world scale and gesture based aim while moving -- and you're always moving in WFA/WFF...
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