Function wined3d_config 

pub fn wined3d_config(wined3d: Wined3d, config: Option<&str>) -> String

The WINE_D3D_CONFIG value for the renderer wined3d on top of config.

config is the value the rules’ own env entries leave the variable at (None when they do not set it, or remove it). The renderer comes first and the other options of config are kept, while a renderer option there is dropped: the setting decides the renderer. OpenGL is set as explicitly as Vulkan, so a process that asks for it does not inherit Vulkan from the process that started it.