wayland: implement alpha_modifier_v1

src/ifs/wl_surface/wp_alpha_modifier_surface_v1.rs

@@ -0,0 +1,78 @@
+use {
+    crate::{
+        client::{Client, ClientError},
+        ifs::wl_surface::WlSurface,
+        leaks::Tracker,
+        object::{Object, Version},
+        wire::{wp_alpha_modifier_surface_v1::*, WpAlphaModifierSurfaceV1Id},
+    },
+    std::rc::Rc,
+    thiserror::Error,
+};
+
+pub struct WpAlphaModifierSurfaceV1 {
+    pub id: WpAlphaModifierSurfaceV1Id,
+    pub version: Version,
+    pub client: Rc<Client>,
+    pub surface: Rc<WlSurface>,
+    pub tracker: Tracker<Self>,
+}
+
+impl WpAlphaModifierSurfaceV1 {
+    pub fn new(id: WpAlphaModifierSurfaceV1Id, surface: &Rc<WlSurface>, version: Version) -> Self {
+        Self {
+            id,
+            version,
+            client: surface.client.clone(),
+            surface: surface.clone(),
+            tracker: Default::default(),
+        }
+    }
+
+    pub fn install(self: &Rc<Self>) -> Result<(), WpAlphaModifierSurfaceV1Error> {
+        if self.surface.alpha_modifier.is_some() {
+            return Err(WpAlphaModifierSurfaceV1Error::Exists);
+        }
+        self.surface.alpha_modifier.set(Some(self.clone()));
+        Ok(())
+    }
+}
+
+impl WpAlphaModifierSurfaceV1RequestHandler for WpAlphaModifierSurfaceV1 {
+    type Error = WpAlphaModifierSurfaceV1Error;
+
+    fn destroy(&self, _req: Destroy, _slf: &Rc<Self>) -> Result<(), Self::Error> {
+        self.surface.alpha_modifier.take();
+        self.surface.pending.borrow_mut().alpha_multiplier = Some(None);
+        self.client.remove_obj(self)?;
+        Ok(())
+    }
+
+    fn set_multiplier(&self, req: SetMultiplier, _slf: &Rc<Self>) -> Result<(), Self::Error> {
+        let multiplier = if req.factor == u32::MAX {
+            None
+        } else {
+            Some(((req.factor as f64) / (u32::MAX as f64)) as f32)
+        };
+        self.surface.pending.borrow_mut().alpha_multiplier = Some(multiplier);
+        Ok(())
+    }
+}
+
+object_base! {
+    self = WpAlphaModifierSurfaceV1;
+    version = self.version;
+}
+
+impl Object for WpAlphaModifierSurfaceV1 {}
+
+simple_add_obj!(WpAlphaModifierSurfaceV1);
+
+#[derive(Debug, Error)]
+pub enum WpAlphaModifierSurfaceV1Error {
+    #[error(transparent)]
+    ClientError(Box<ClientError>),
+    #[error("The surface already has an alpha modifier extension attached")]
+    Exists,
+}
+efrom!(WpAlphaModifierSurfaceV1Error, ClientError);