I found the light effect in this image special, which I can achieve with a photo filter in a 2D graphic in Photoshop. But imagine in an interactive game scene, can we render it directly or add a filter after it's rendered in each frame?
@echo Absolutely---in modern real time rendering engines it's pretty common to do multiple rendering passes, with all sorts of 2D image processing in between. Here's a fairly old article from NVIDIA on how to do real time glow, but it would be cool if someone could dig up a more recent technique (or even just a cool YouTube video showing off more recent "glow" techniques in games!)
I just checked the real time glow website. It basically takes the alpha channel as the glow source since it contains the brighter parts of the object. After choosing the source, some convolutional layers are applied and added to create the halo effect. It is a simple but effective way to do such things.