implement wlr-gamma-control-unstable-v1

src/ifs/zwlr_gamma_control_v1.rs

@@ -0,0 +1,166 @@
+use {
+    crate::{
+        backend::{BackendGammaLut, BackendGammaLutElement},
+        client::{Client, ClientError, ClientId},
+        clientmem::{ClientMem, ClientMemError},
+        ifs::{
+            wl_output::OutputGlobalOpt, zwlr_gamma_control_manager_v1::ZwlrGammaControlManagerV1,
+        },
+        leaks::Tracker,
+        object::{Object, Version},
+        wire::{ZwlrGammaControlV1Id, zwlr_gamma_control_v1::*},
+    },
+    std::rc::Rc,
+    thiserror::Error,
+};
+
+pub struct ZwlrGammaControlV1 {
+    id: ZwlrGammaControlV1Id,
+    client: Rc<Client>,
+    version: Version,
+    output: Rc<OutputGlobalOpt>,
+    pub tracker: Tracker<Self>,
+}
+
+impl ZwlrGammaControlV1 {
+    pub fn new(
+        id: ZwlrGammaControlV1Id,
+        manager: &Rc<ZwlrGammaControlManagerV1>,
+        output: Rc<OutputGlobalOpt>,
+    ) -> Self {
+        Self {
+            id,
+            client: manager.client.clone(),
+            version: manager.version,
+            output,
+            tracker: Default::default(),
+        }
+    }
+
+    pub fn id(&self) -> (ClientId, ZwlrGammaControlV1Id) {
+        (self.client.id, self.id)
+    }
+
+    pub fn send_gamma_size(&self, size: u32) {
+        self.client.event(GammaSize {
+            self_id: self.id,
+            size,
+        });
+    }
+
+    pub fn send_failed(&self) {
+        self.client.event(Failed { self_id: self.id });
+    }
+
+    pub fn gamma_lut_size(&self) -> Option<u32> {
+        self.output
+            .node()
+            .and_then(|node| node.global.connector.connector.gamma_lut_size())
+    }
+
+    fn detach(&self) {
+        if let Some(node) = self.output.node()
+            && let Some(active_zwlr_gamma_control) = node.active_zwlr_gamma_control.get()
+            && active_zwlr_gamma_control.id() == self.id()
+        {
+            node.active_zwlr_gamma_control.set(None);
+            let _ = node.set_gamma_lut(None);
+        }
+    }
+}
+
+// Wayland's LUT is ([red], [green], [blue]). DRM's LUT is [(red, green, blue, _)]. Both are u16.
+fn wayland_gamma_lut_to_drm_gamma_lut(data: &[u16]) -> Vec<BackendGammaLutElement> {
+    let elem_count = data.len() / 3;
+    let (red, rest) = data.split_at(elem_count);
+    let (green, blue) = rest.split_at(elem_count);
+    red.iter()
+        .copied()
+        .zip(green.iter().copied())
+        .zip(blue.iter().copied())
+        .map(|((red, green), blue)| BackendGammaLutElement {
+            red,
+            green,
+            blue,
+            reserved: 0,
+        })
+        .collect()
+}
+
+impl ZwlrGammaControlV1RequestHandler for ZwlrGammaControlV1 {
+    type Error = ZwlrGammaControlV1Error;
+
+    fn set_gamma(&self, req: SetGamma, _slf: &Rc<Self>) -> Result<(), Self::Error> {
+        let fail = || {
+            self.detach();
+            self.send_failed();
+        };
+
+        let Some(node) = self.output.node() else {
+            return Ok(());
+        };
+
+        // if the active gamma control isn't us, that implies we are not valid, and have already
+        // sent a failed event
+        if node.active_zwlr_gamma_control.get().map(|v| v.id()) != Some(self.id()) {
+            return Ok(());
+        }
+
+        let Some(gamma_lut_size) = self.gamma_lut_size() else {
+            fail();
+            return Ok(());
+        };
+
+        // 3 color channels
+        let data_size = gamma_lut_size * 3;
+
+        let mut gamma_lut = vec![];
+        Rc::new(ClientMem::new_private(
+            &req.fd,
+            (2 * data_size) as _,
+            true,
+            Some(&self.client),
+            None,
+        )?)
+        .offset(0)
+        .read(&mut gamma_lut)?;
+        let gamma_lut = &gamma_lut[..data_size as _];
+
+        let gamma_lut = wayland_gamma_lut_to_drm_gamma_lut(gamma_lut);
+        let gamma_lut = Rc::new(BackendGammaLut::new(gamma_lut));
+        if node.set_gamma_lut(Some(gamma_lut)).is_err() {
+            fail();
+            return Ok(());
+        }
+
+        Ok(())
+    }
+
+    fn destroy(&self, _req: Destroy, _slf: &Rc<Self>) -> Result<(), Self::Error> {
+        self.detach();
+        self.client.remove_obj(self)?;
+        Ok(())
+    }
+}
+
+object_base! {
+    self = ZwlrGammaControlV1;
+    version = self.version;
+}
+
+impl Object for ZwlrGammaControlV1 {
+    fn break_loops(&self) {
+        self.detach();
+    }
+}
+
+simple_add_obj!(ZwlrGammaControlV1);
+
+#[derive(Debug, Error)]
+pub enum ZwlrGammaControlV1Error {
+    #[error(transparent)]
+    ClientError(Box<ClientError>),
+    #[error(transparent)]
+    CLientMemError(#[from] ClientMemError),
+}
+efrom!(ZwlrGammaControlV1Error, ClientError);