Random dot kinematogram leaves visible traces

[ThetaS]

Hi all,

When implementing dot kinematogram with C Sharp Transform in Bonsai, I found that the dots will leave a visible trace as they move. I checked the RDK implemented in the Bonsai official scripting tutorial and it also has this problem. I suppose it's due to some buffering or frame refresh rate issues. Any ideas on how to solve this problem? Thanks.

[bruno-f-cruz]

Can you include your project? Thanks!

[ThetaS]

Hi Bruno,

Sorry for suspending this for reallly long time. Attached is my Bonsai layout and C# code. I also have question regarding how to construct this kind figure-ground visual stimulus in general, especially using the default "Draw Grating" scheme. It seems like the draw grating does not have a mask option. Do I need to code it from scratch suppose I want to have two gratings overlay on each other with one as foreground and one as background? Thanks a lot.
RDK.zip

[bruno-f-cruz]

I think using RenderFrame instead of UpdateFrame to generate your RDK might fix it.

[ThetaS]

Thanks, will try to implement that