Nikita Lisitsa

Yay, it works! So instead of just mixing with the previous frame, I'm mixing with a temporally reprojected previous frame, which eliminates the dizzy blurring due to camera movements and only preserves the "motion blur" of the cars.

#gamedev #indiedev

Jun 26, 2023 at 1:52pmWeb
Show threadEniko (moved ➡ gamedev.place)Jun 26, 2023
@lisyarus how do you do the reprojection?
Show threadNikita LisitsaJun 26, 2023
@eniko I have this frame's depth buffer and camera matrix, which can be used to reconstruct world-space position of the pixel. Then, I use the previous frame's camera matrix to figure the screen-space position of this world-space point in the previous frame, and use it to sample the previous frame!
Show threadEniko (moved ➡ gamedev.place)Jun 26, 2023
@lisyarus very nice :D
Show threadFellJun 26, 2023

@lisyarus @eniko I always thought you need a motion buffer to do that.

But I guess if all that's moving is the camera, the camera matrices are enough.

You'll run into problems once you want to add other animations and effects on the map though...

Show threadNikita LisitsaJun 26, 2023
@fell @eniko I'm OK with animated stuff being blurred, that's the whole point :) You won't get true motion blur, though, something like light trails at night aren't possible with this approach.
Show threadFellJun 26, 2023

@[email protected] @eniko Light trails would be possible if you render the bright parts of the image into a separate buffer and blur that.

Basically a classic bloom, but blended with the previous frame instead of gaussian blur.

Show threadNikita LisitsaJun 26, 2023
@fell @eniko But I'll still need motion vectors in this case?
Show threadYinYin FalconJun 26, 2023
@lisyarus I wanna see this for car light trails :D
Show threadNikita LisitsaJun 26, 2023
@YinYinFalcon Unfortunately, this method doesn't work for light trails, for that you need true motion blur :(
Show thread~Jun 26, 2023
@lisyarus wowww that's a clever effect, I'm impressed!