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3d tracing

Hi, might be a simple one but i can’t figure it out.
i have a point moving around in 3d enviroment (ex9 renderer)
and what i would like to do is to get it to leave a trace,where ever it been,so basically have that point drawing a line wherever it goes.
i was able to get it to work in a non proper way,which makes the
renderer blink,by hooking a vector node directly to the renderer
but i can’t figure out the right way to do it.
any suggestions?

two possible methods:

  1. simply disable the clear pin on your renderer. then the point leaves a trace
  2. use queue to store the values if the trail doesn’t have to be infinitely long. I wouldn’t recommend spreadcounts > 2000 or so. If you don’t sample every frame, your spread will get a lot smaller. use a “line” node to connect the points.

thanks.
its a bit strange… what you are suggesting in #1 works but when i try
to view it fullscreen the whole renderer blinks.then when i alt-1 it
i turns the background black. bug?

not a bug. but when the renderer switches mode (resizes), strange things (artefacts or other false pixels) can be drawn. Normally, theese errors would be cleared but because “clear” is turned off, the errors remain.
Just add a keyboard an keymatch node to the clear pin to clear the renderer on keystroke after setting it to fullscreen. then it should work again

not a bug. Normally, these errors would be cleared but because “clear” is turned off, the errors remain.

i´ll log this as a bug.

ahlo. pls try the different “fullscreen swap effects”. select renderer (ex9) with an inspektor and locate that pin. then try going fullscreen with the different settings. maybe one of them works different…

thanks
after messing with it for a while ; ] it worked.
i had to switch between the “fullscreen swap effects” options for a while and then it worked.

@joreg: but why not fix the problem by always clearing the buffer just once when switching to fullscreen? doing this manually is a little awkward, as there is no clean information whether fullscreen gets activated (apart from using Keyboard…)

And have a DynamicTexture (Memory) node which takes a pointer to an arbitary memory area and use that as a texture - for all friends of the artifacts when going to fullscreen with clear disabled

harsh! you just sent me looking for DynamixTexture (Memory). in vain.
;)