Implement MSAA for triangle pipeline in iced_wgpu

wgpu/src/settings.rs

@@ -7,4 +7,26 @@ pub struct Settings {
     ///
     /// If `None` is provided, a default system font will be chosen.
     pub default_font: Option<&'static [u8]>,
+
+    /// The antialiasing strategy that will be used for triangle primitives.
+    pub antialiasing: Option<MSAA>,
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum MSAA {
+    X2,
+    X4,
+    X8,
+    X16,
+}
+
+impl MSAA {
+    pub(crate) fn sample_count(&self) -> u32 {
+        match self {
+            MSAA::X2 => 2,
+            MSAA::X4 => 4,
+            MSAA::X8 => 8,
+            MSAA::X16 => 16,
+        }
+    }
 }