High-Speed Global Shadows Update Bug

The bug occurs when global shadows are enabled in a place and the game involves the player moving at high speed, either in a car, plane, or moving on foot with an increased walk speed. As the player moves the lighting system cannot keep up and has ugly fake shadows appear in front of the player, or other times shadows do no appear when they should. It seems like the lighting chunks have trouble loading it, but I don’t know enough to say if that is the problem or not. Here is a video showing the bug along with time stamps of it occurring.

(For reference, the speed displayed in the video is 1/3rd of the cars true speed in studs per second. So 100 MPH=300 studs per second)

0:04: At the vehicle starts to accelerate off to the right side you can see some dark spots quickly appear and then disappear on the snow. This then continues as the vehicle moves.

0:10: As the car goes through the turn you can see dark spots appear and disappear in front of the vehicle at about 100-150 studs in front of it.

0:15: Again, the dark spots appear and disappear as the car continues over the bumps.

0:31: When the vehicle enters a tunnel the shadow half appears, resulting in a dark spot on the ground, but abruptly ends even though the track should be dark.

0:51: Going through another tunnel, the dark spots again appear and half of the tunnel casts a shadow on the ground. But then as the vehicle gets closer the shadow pops in in two different spots.

0:56: More dark spots appear and disappear in front of the vehicle as it goes down and then up the hill. The dark spots appear/disappearing then continue until the end of the video.

Again, I’ve seen this in almost every place that I enable global lighting. It affects both ROBLOX player and ROBLOX studio, although it is less noticable in Studio while testing a game. The lights on the vehicle do not cause it and it can be replicated without the lights.

Specs: Intel i5 2400, GTX 670. Quality level set to max, Link to place in video.

EDIT: Screen shots taken from the video highlighting the problem areas.

The dark shadows that appear in front of the vehicle and off to the side of the terrain

The second tunnel not having proper shadows loaded despite being very close to it.


I’ve always noticed this and I really dislike it, it is similar to an experience I get when building a tall wall or skyrise building - dynamic lighting will cut off at a certain distance from the player, and any changes there will be delayed as non-important.

I experience another similar issue if you’re a medium distance away from a dynamic light that is turning on or off - it will take a few moments for the light to actually appear or disappear if it’s been told to.

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