how to change the screen layer (frame buffer) number for python

[citius-p]

I have a python program that runs omxplayer in one thread and pygame surfaces manipulation in another.

Currently the omxplayer video size and position has been restricted to one area of the screen and the pygame surfaces sit around it. So both are visible.

I am wanting to run the video full screen and have the surfaces transparent on top of it.

I can set the omxplayer to use layer zero, but is there a way of forcing the pygame output to a higher layer number ?

[dividuum]

You could place the video below the frame buffer layer instead of trying to move the frame buffer itself.

[citius-p]

Thanks for the suggestion.

I have tried that, but omxplayer will not accept a negative layer number

So, I have to try and move the pygame output into a positive layer number

[dividuum]

I have tried that, but omxplayer will not accept a negative layer number

It does, at least with the version I have here on my test Pi4:

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$ omxplayer --layer -128 demo1/optical.mp4 

You can confirm that by running vcgencmd dispmanx_list and check the layer numbers. The framebuffer is at -127 by default. Being XRGB8888, there's no transparency, so the video layer below it isn't visible through the framebuffer and you cannot see the video playing in this configuration:

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root@raspberrypi:~# vcgencmd dispmanx_list
display:2 format:YUV_UV transform:0 layer:-128 640x368 src:0,0,640,360 dst:0,0,1920,1080 cost:1216 lbm:10240 (ignore lower layers) 
display:2 format:XRGB8888 transform:0 layer:-127 1920x1080 src:0,0,1920,1080 dst:0,0,1920,1080 cost:1156 lbm:0 

[citius-p]

For some reason I had it in my head that the 'layer parameter was '-l'. Using the full '--layer' now lets me go negative

However, on my my Pi 2 using -128 for omxplayer gives sound but no video. I have a Pi 3 which I will have to hook up to try.

I am still wondering if there is a way of wrestling the command line away from -127.

[dividuum]

However, on my my Pi 2 using -128 for omxplayer gives sound but no video.

That's expected and what I meant with my XRGB8888 note. If the layer above isn't transparent, a video behind it will not be visible.

I am still wondering if there is a way of wrestling the command line away from -127.

Probably, but pointless: Just use layers relative to -127. Only the relative layer position is relevant.

[citius-p]

Thanks, for the update.

I will now move forward as you suggest.