Introduce FingerId (#3783)

src/platform_impl/web/event.rs

@@ -0,0 +1,32 @@
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct DeviceId(i32);
+
+impl DeviceId {
+    pub fn new(pointer_id: i32) -> Self {
+        Self(pointer_id)
+    }
+
+    pub const fn dummy() -> Self {
+        Self(-1)
+    }
+}
+
+#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct FingerId {
+    pointer_id: i32,
+    primary: bool,
+}
+
+impl FingerId {
+    pub fn new(pointer_id: i32, primary: bool) -> Self {
+        Self { pointer_id, primary }
+    }
+
+    pub const fn dummy() -> Self {
+        Self { pointer_id: -1, primary: false }
+    }
+
+    pub fn is_primary(self) -> bool {
+        self.primary
+    }
+}