I have an application that uses Qt 5.6 for various purposes and runs on an embedded device. I currently have it rendered via eglfs in the buffer of the Linux frame on the connected display, but I also want to be able to capture data and send it to a single-color LED display (the device will either have this unit or a full video device, never both at the same time) .
Based on what I have found so far on the net, the best approach is this:
- disable anti-aliasing;
- set Qt for the display device to 1 bit / pixel;
- select the font 1bpp, gray color is not allowed; and
- somehow capture the graphic scene that Qt produces so that I can transfer it to the display.
This is just the last question I have problems with. I suspect that I need to create the surface of some description and push it onto the "stack" of the Qt display, but I cannot find good examples of how to do this.
How to do this and, believing that I am right, is there a synchronization method used to ensure that I get only full buffers from the surface (i.e. without a gap)?
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