Hello again Peter,
I’m sorry, I wasn’t home yesterday, so only answering to you now… So, the bubble test you sent me is at least showing something… Let me try to describe it to you.
I see just a blue dot at start, growing slowly and slowly fading away. But it do not go up… It’s circling (to be more precise I could say it’s spiraling). Huh, it’s even more complicated than that… On its origin point, it’s not moving at all… It’s only growing and fading away. But when I double-click in the renderer it’s changing… Let’s imagine the renderer window is divided in its X and Y axis in the middle of the screen. The meeting point of those 2 axis is the center of the screen. It’s also the place where the bubble is born. If I click below the horizontal split, on the right hand side of the screen, the bubble starts spiraling anti-clockwise. The farther it is from the split, the bigger the spiral. If I click up the middle horizontal split, still right hand side from the vertical split, it’s also spiraling anti-clockwise. Everything on the left hand side of the vertical split makes the rotation clockwise.
For the Update mode, I was already in Precise mode. I’ve switched to Fast, and … well, there is a difference, but only in the spiral speed.
As well, after various tests, it seems I also get anti-clockwise spirals on the left hand side, so, it could be random seed…
But in all the tests, I couldn’t see any bubble up effect. It’s very much more a spiraling effect to me.