Is it possible to stop the buffer from overflowing if you re-draw the entire screen? about console_engine

[VincentFoulon80]

I wasn't aware of this kind of issue, I originally tried to avoid overdrawing because printing chars is notoriously slow on most terminals (sometimes worse on Windows)

[lesleyrs]

Yea all I'm doing right now is just filling a full screen (actual screen) with dots which is a lot. I think it takes about 4 ms if I saw correctly (debug mode).

However speed is not my problem right now, I set the frame rate at 1 per second but because it immediately flushes if I draw more than a few rows it's just ignored and flushes instantly. Then whatever is drawn on top either flickers or doesn't show.

The part that I don't understand is that avoiding overdrawing can't be the fix to my problem as the FIRST frame in console_engine already loads the way it should.

In console_engine if you call:
let mut engine = console_engine::ConsoleEngine::init(160, 45, 1).unwrap();

It draws the entire screen (for me anyway) after waiting the full 1 second which is correct.

But my behavior on a simple project is when I draw the full screen this way it just flushes instantly, no waiting unless I draw a tiny area. I think I'll keep looking into this.

https://docs.rs/crossterm/latest/crossterm/macro.queue.html

Queued commands must be flushed to the underlying device to be executed. This generally happens in the following cases:

When flush is called manually on the given type implementing io::Write.
The terminal will flush automatically if the buffer is full.
Each line is flushed in case of stdout, because it is line buffered.

Edit: I see you have another draw function that uses execute!, but not sure about the difference in usage between them.

[lesleyrs]

Ok some friendly guy in the crossterm discord helped me solve the problem. I had to replace:
let mut stdout = stdout();
with
let mut stdout = BufWriter::with_capacity(640000, stdout());

I guess the reason you didn't need to do this is because you are using screens as the buffer and that magically solves it? Problem solved anyway :D

[VincentFoulon80]

Interesting to know though, thank you for reporting back !