| 3 Jan 2024 |
 K900 | Not really | 10:40:57 |
| K900 | The whole point of Looking Glass is that it works like a normal VM | 10:41:09 |
| K900 | With a separate window and passed through input and such | 10:41:24 |
| K900 | But it's rendering on a passed-through GPU | 10:41:35 |
 crushing-smite | why can't it be achieved solely via the means of KVM? | 10:42:07 |
| K900 | Because there's no standard way to get the rendered image from the VM to the host | 10:43:06 |
| K900 | That's really all Looking Glass does | 10:43:16 |
| crushing-smite | In reply to @k900:0upti.me
Because there's no standard way to get the rendered image from the VM to the host could you elaborate more? | 10:43:32 |
| K900 | It's basically recording the screen in the VM and piping the video to the host | 10:43:34 |
| crushing-smite | basically, there are shenanigans like spice-vnc, right? | 10:43:50 |
| K900 | Yes, but those are slow | 10:44:04 |
| K900 | Because they rely on the virtualized GPU | 10:44:14 |
| crushing-smite | what makes looking glass fats in comparison to? | 10:44:33 |
| K900 | It's fine for simple workloads but not for games | 10:44:35 |
| K900 | Looking Glass by itself isn't rendering anything | 10:44:52 |
| K900 | Windows is rendering to the passed-through GPU | 10:45:05 |
| K900 | And Looking Glass is recording that and piping it to the host so you can see the output in a window | 10:45:32 |
| K900 | Instead of switching the input on your display | 10:45:40 |
| K900 | Or using a second display or whatever | 10:45:46 |
| crushing-smite | So, looking glass is fast because it has direct memory access to GPU, while stuff like spice-vnc has to wait while rendered stuff gets back to guest, and then it plugs into the videostream? | 10:45:56 |
| K900 | No | 10:46:05 |
| K900 | SPICE doesn't use your real GPU at all | 10:46:15 |
| crushing-smite | I mean, if there is a GPU involved, otherwise, it's just a vnc client | 10:46:35 |
| crushing-smite | * I mean, if there is a GPU involved, regardless of, it's just a vnc client | 10:46:44 |
| crushing-smite | as if I was streaming over the net | 10:47:04 |
| K900 | No, if you pass through a GPU, you'll get no output on SPICE | 10:47:08 |
| crushing-smite | so, a defficiency of a protocol | 10:47:10 |
| K900 | You'll only get output on the monitor connected to the GPU | 10:47:26 |
| crushing-smite | how did people get image from gpu passthrough in the days before looking glass? | 10:48:05 |
| K900 | Because SPICE only works with the virtualized QEMU GPU | 10:48:09 |
