Half-Life: Alyx - how to optimise your game for streaming and spectating
Half-Life: Alyx is one of 2020's most anticipated games, but its nature as a VR exclusive makes it more challenging to stream compared to most games.
This is true for Half-Life: Alyx, as well as other VR games, of course, but Valve has a few solutions to this problem. To help make watching Alyx streams more enjoyable, the developer released a few guidelines for streamers to help them create a smooth, jitter-free experience for viewers.
This is why Half-Life: Alyx has a customisable spectator mode, specifically designed so that you can control how the game translates VR visuals to a flat, 2D screen.
Spectator mode eye settings
The first thing you're going to decide is the perspective of the the spectator. You can choose between left or right eye for this. Valve recommends picking the eye you're going to aim down. So pick right if you tend to close your left eye while aiming down sights.
Spectator mode smooth settings
In the same menu, you can also choose to turn smoothing on or off. The setting smooths out the jitter that results from turning quickly in-game. When turned on, you can pick from low, medium or high. This only applies to the spectator view, of course.
This effect is applied in real-time, and comes with a very small performance hit.
Spectator mode HUD settings
The HUD is another element that may not always make sense to show viewers. This option allows you turn certain HUD elements on/off specifically for the spectator view. By default, the HUD shows health, ammo, resin count and any items you're carrying.
But you can turn the HUD completely off, or control the size of it from small, medium, and large.
Outside of the simple settings outlined above, Alyx also offers deeper customisation through the advanced menu. These options are found in the game's dev console, which is brought up by hitting the tilde (~) key. Before that, however, you need to enable access to the console by adding "-console -vconsole" to the game's launch properties on Steam.
Here's what you get by enabling the console.
Full in-camera smoothing
This is a more aggressive form of smoothing that's designed for a more cinematic look. It smooths all three axes of rotation, but its big downside is that it also applies to your own view as well as the spectator view.
To enable this feature, bring up the console (~) and type these commands:
- vr_camera_decay_roll_halflife 0.5.
- vr_camera_decay_yaw_pitch_halflife 0.09.
These values can be adjusted further, and the numbers represent seconds. For example, it takes your camera 0.5 seconds to get "halfway between the currently-displayed amount of camera roll and your actual head position." In other words, the higher this goes the more it will tune out small rotations, adding more lag.
You can disable both of these by typing "vr_camera_decay_roll_halflife 0", and "vr_camera_decay_yaw_pitch_halflife 0".
Advanced spectator mode HUD settings
Likewise, the spectator HUD can also be further tweaked from its default options. You can bring up the console and type "hlvr_spectator_hud_size 100" to change the size of the spectator HUD. You can go between 50 and 150, or 0 to remove it entirely. Keep in mind that this is only visible to viewers.