Add camera torch and zoom

[tomm1e]

Handles screen events by video source. I put the input event logic for camera in a new folder (src/im) to keep things organized. New video sources can add event logic there.

New shortcuts:

• MOD+q: Camera toggle torch
• MOD+1: Camera zoom in
• MOD+2: Camera zoom out

New CLI options:

• --camera-torch (Turn on torch when starting)
• --camera-zoom-step=0.05 (Adjust step value)

Tested on Samsung Galaxy A52 5G, no issues.

Closes #4670, #4903

Note: I think some functions such as apply_orientation_transform could be put into a util file since those could be used across all video source event handlers.

[rom1v]

Thank you 👍 Looks great.

However, to be honest, it might take some time (at least weeks) before I can review properly and merge.

FYI, in the past, I had started a branch (torch, which I just pushed), but I stopped before adding the mechanism for camera controls.

[Tiger-roar13]

Thanks, I'm getting an error .\scrcpy: unknown option -- camera-torch

scrcpy is working happily without the camera-torch option

I assume this isn't in the latest version yet, 3.3.3 ?

[rom1v]

I assume this isn't in the latest version yet, 3.3.3 ?

No, it's not merged. It will be in the future.

(Locally, I started to rebase it onto the SDL3 branch.)

[rom1v]

Here are some updates about my local work.

I rebased on the (current) SDL3 branch (#6216).

First, in preliminary commits, I enabled "control" (shortcuts) for a camera video source directly in input_manager.c (eliminating the need for a separate im/camera.c with code duplication) and implemented a first camera "control" for the existing "reset video" shortcut.

Next, I addressed some threading issues (the control to switch the torch is called from the controller thread, but requestBuilder was being set from the camera thread).

I also changed the shortcuts from "toggle torch" to explicit "turn on" and "turn off", allowing users to set a specific mode without needing to know the current state (consistent with "turn screen on/off").

You're the main author of the --camera-torch commit and co-author of two other commits.

The current working branch is here: https://github.com/Genymobile/scrcpy/commits/camera_control.11/

I still need to rebase the zoom feature (with your authorship).