use anyhow::Context as _;use std::sync::Arc;use util::ResultExt; pub struct WgpuContext {    pub instance: wgpu::Instance,    pub adapter: wgpu::Adapter,    pub device: Arc<wgpu::Device>,    pub queue: Arc<wgpu::Queue>,    dual_source_blending: bool,} impl WgpuContext {    pub fn new() -> anyhow::Result<Self> {        let device_id_filter = match std::env::var("ZED_DEVICE_ID") {            Ok(val) => parse_pci_id(&val)                .context("Failed to parse device ID from `ZED_DEVICE_ID` environment variable")                .log_err(),            Err(std::env::VarError::NotPresent) => None,            err => {                err.context("Failed to read value of `ZED_DEVICE_ID` environment variable")                    .log_err();                None            }        };         let instance = wgpu::Instance::new(&wgpu::InstanceDescriptor {            backends: wgpu::Backends::VULKAN | wgpu::Backends::GL,            flags: wgpu::InstanceFlags::default(),            backend_options: wgpu::BackendOptions::default(),            memory_budget_thresholds: wgpu::MemoryBudgetThresholds::default(),        });         let adapter = smol::block_on(Self::select_adapter(&instance, device_id_filter))?;         log::info!(            "Selected GPU adapter: {:?} ({:?})",            adapter.get_info().name,            adapter.get_info().backend        );         let dual_source_blending_available = adapter            .features()            .contains(wgpu::Features::DUAL_SOURCE_BLENDING);         let mut required_features = wgpu::Features::empty();        if dual_source_blending_available {            required_features |= wgpu::Features::DUAL_SOURCE_BLENDING;        } else {            log::warn!(                "Dual-source blending not available on this GPU. \                Subpixel text antialiasing will be disabled."            );        }         let (device, queue) = smol::block_on(adapter.request_device(&wgpu::DeviceDescriptor {            label: Some("gpui_device"),            required_features,            required_limits: wgpu::Limits::default(),            memory_hints: wgpu::MemoryHints::MemoryUsage,            trace: wgpu::Trace::Off,            experimental_features: wgpu::ExperimentalFeatures::disabled(),        }))        .map_err(|e| anyhow::anyhow!("Failed to create wgpu device: {e}"))?;         Ok(Self {            instance,            adapter,            device: Arc::new(device),            queue: Arc::new(queue),            dual_source_blending: dual_source_blending_available,        })    }     async fn select_adapter(        instance: &wgpu::Instance,        device_id_filter: Option<u32>,    ) -> anyhow::Result<wgpu::Adapter> {        if let Some(device_id) = device_id_filter {            let adapters: Vec<_> = instance.enumerate_adapters(wgpu::Backends::all()).await;             if adapters.is_empty() {                anyhow::bail!("No GPU adapters found");            }             let mut non_matching_adapter_infos: Vec<wgpu::AdapterInfo> = Vec::new();             for adapter in adapters.into_iter() {                let info = adapter.get_info();                if info.device == device_id {                    log::info!(                        "Found GPU matching ZED_DEVICE_ID={:#06x}: {}",                        device_id,                        info.name                    );                    return Ok(adapter);                } else {                    non_matching_adapter_infos.push(info);                }            }             log::warn!(                "No GPU found matching ZED_DEVICE_ID={:#06x}. Available devices:",                device_id            );             for info in &non_matching_adapter_infos {                log::warn!(                    "  - {} (device_id={:#06x}, backend={})",                    info.name,                    info.device,                    info.backend                );            }        }         instance            .request_adapter(&wgpu::RequestAdapterOptions {                power_preference: wgpu::PowerPreference::None,                compatible_surface: None,                force_fallback_adapter: false,            })            .await            .map_err(|e| anyhow::anyhow!("Failed to request GPU adapter: {e}"))    }     pub fn supports_dual_source_blending(&self) -> bool {        self.dual_source_blending    }} fn parse_pci_id(id: &str) -> anyhow::Result<u32> {    let mut id = id.trim();     if id.starts_with("0x") || id.starts_with("0X") {        id = &id[2..];    }    let is_hex_string = id.chars().all(|c| c.is_ascii_hexdigit());    let is_4_chars = id.len() == 4;    anyhow::ensure!(        is_4_chars && is_hex_string,        "Expected a 4 digit PCI ID in hexadecimal format"    );     u32::from_str_radix(id, 16).context("parsing PCI ID as hex")} #[cfg(test)]mod tests {    use super::parse_pci_id;     #[test]    fn test_parse_device_id() {        assert!(parse_pci_id("0xABCD").is_ok());        assert!(parse_pci_id("ABCD").is_ok());        assert!(parse_pci_id("abcd").is_ok());        assert!(parse_pci_id("1234").is_ok());        assert!(parse_pci_id("123").is_err());        assert_eq!(            parse_pci_id(&format!("{:x}", 0x1234)).unwrap(),            parse_pci_id(&format!("{:X}", 0x1234)).unwrap(),        );         assert_eq!(            parse_pci_id(&format!("{:#x}", 0x1234)).unwrap(),            parse_pci_id(&format!("{:#X}", 0x1234)).unwrap(),        );    }}