Falling through floor in runtime after changing scenes UPBGE 0.3

We start with a title page, and press space to begin.

This switches to a second scene. We’re looking down on a city through an orthographic view camera.

Pressing 1 then switches to another camera within the same scene, which follows along behind a controllable vehicle.

All of this works fine in UPBGE when I hit “P.”

When I export as a runtime, though, the car falls through the street as soon as the scene switch takes place. In the overhead view, I can see the tiny car vanish, and when I switch cameras, there’s nothing but the car and the sky all around.

Any ideas?

I think I had the same problem in my marble game.
Suppose the physics calculation comes too late because of loading.
Would explain why this doesn’t happen when all is already in memory when starting from within blender.
Adding a delay sensor might help.

Thanks! Based on what you said, I just tried moving my car way up in the air over the street so it has more time to fall. The runtime worked this time!

Without raising your car in the air, you might try raising the physics substeps of your scene.

A low amount of substeps is known to cause non-collision detections with fast moving objects, because the scene is calculating only 1 substep at a time. Here’s also the tooltip description when you hover over the substep value panel:

image

1 Like

Thank you! I moved the car back down and increased the substeps to two, and it worked like a charm.

I have another solution as implementing this one messed up the rest of my physics. I just placed an object in the scene that is invisible at runtime and non colidable. Then set a logic node set up on my player that falls threw floor. The node set up says that on initialize delay for however long you want, then after the delay timer it will get the wold position of the object i added thats invisible, then move my player to that location once. Worked well for me. I know this is a super late reply but i figured it would be good for others still.