4 ms·
> And of course your next keystroke is not zero copy. It needs to be sent to the GPU and the texture needs to be updated. No textures need to be updated. The t
by CyberRabbi 5y ago
> And of course your next keystroke is not zero copy. It needs to be sent to the GPU and the texture needs to be updated.
No textures need to be updated. The texture stays in VRAM across each frame, just need to change which texture the character cell points to. That is zero-copy.
If you were to do this with a software rendered terminal, at minimum the software would tell the windowing system which region of the window changed and then copy that region to VRAM. That’s only if the window system supports region updates, if not you’d need to copy the entire window to VRAM each frame. Much slower than just twiddling a pointer to a texture.
- geokon 5y agoShow me the numbers.. https://danluu.com/term-latency/ https://danluu.com/term-latency/
- CyberRabbi 5y agoWell all these data tell us is that alacritty has more latency than some terminals and less latency than others. It does not tell us why it displays the latency that it does. In other words, correlation is not causation. Many other factors are at play here. I’ve given you a rationale for why the GPU rendering technique inherently minimizes latency over the software rendered technique. Can you provide a rationale for why software rendered terminals would have an inherent advantage in terms of latency?