There are lots of visual effects that we are starting to maybe mix up.
Lens flare is reflections of the lenses themselves inside the lens. This is caused by light that doesn't pass through the lens properly (ie, through all the elements), and so illuminates intermediate elements and they are reflected in other elements etc etc... ie, the sun or a bright light just outside of the lenses field of view.
Then you have glare. The 'flare' on our headlights is actually glare. With an ideal lens and sensor and optical properties, glare would be super smooth, and, assuming we had a really high resolution 'bloom' map in Racer, then the look of headlights with just the bloom map would be correct to real life with an ideal lens/sensor etc.
However, real lenses are not ideal. We have vignetting, distortion, chromatic aberration, and primarily for the 'flare' look, we have the cameras aperture...
A lens with six blades for example, with rounded edges, will give a soft 6 star shape to the bloom. An eight bladed aperture, with straight edges, would tend to give a sharp star with 8 sides.
The 'flare' posted above is probably more for what you might expect from a camera with a relatively non-uniform aperture shape.
In theory, if you squint your eyes while looking at lights, you get a random looking bloom/glare with spikes coming out top and bottom, due to the two horizontal blades across your view (eye lids)
Afaik, lens flare is generated more when the light is out of view but pumping light into the lens. It's probably still evident when light enters the lens properly, and it is heavily over-exposing the image (otherwise you expose down and the lens flares will be much less evident)
The bloom map is done fairly accurately now. Ideally what we need to do is process the bloom map appropriately.
Maxwell Render uses an obstruction or glare map to process the bloom in the scene to make a soft blob look like a cool six sided glare, or whatever you want.
They even provide an 'eye' glare map, so you get the random scattering caused by the eyelids and eye lashes etc.
What Racer NEEDS to do, is have camera types. Each one should use it's own fs_filter, which is set up with it's own properties for blurring, blooming, glare map adjustments, auto exposure speed etc... to better simulate different cameras, or eyes as is the case.
Right now everything is a compromise.
However, to get onto topic properly, the 'flare' map provided by Quadcoremax is ultimately a better all-round compromise, as it looks ok for what you might get with your eye, but also has enough of a look to look correct for what you might see with a camera!
The default one is very 'HQ SLR lens look', but doesn't look anything like an eye glare pattern, or a cheaper camera pattern.
Dave