Draft (very) basic incremental rendering for iced_tiny_skia

core/src/image.rs

@@ -6,7 +6,7 @@ use std::path::PathBuf;
 use std::sync::Arc;
 
 /// A handle of some image data.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Handle {
     id: u64,
     data: Data,
@@ -156,6 +156,34 @@ impl std::fmt::Debug for Data {
     }
 }
 
+impl PartialEq for Data {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (Self::Path(a), Self::Path(b)) => a == b,
+            (Self::Bytes(a), Self::Bytes(b)) => a.as_ref() == b.as_ref(),
+            (
+                Self::Rgba {
+                    width: width_a,
+                    height: height_a,
+                    pixels: pixels_a,
+                },
+                Self::Rgba {
+                    width: width_b,
+                    height: height_b,
+                    pixels: pixels_b,
+                },
+            ) => {
+                width_a == width_b
+                    && height_a == height_b
+                    && pixels_a.as_ref() == pixels_b.as_ref()
+            }
+            _ => false,
+        }
+    }
+}
+
+impl Eq for Data {}
+
 /// A [`Renderer`] that can render raster graphics.
 ///
 /// [renderer]: crate::renderer

core/src/rectangle.rs

@@ -100,6 +100,30 @@ impl Rectangle<f32> {
         }
     }
 
+    /// Returns whether the [`Rectangle`] intersects with the given one.
+    pub fn intersects(&self, other: &Self) -> bool {
+        self.intersection(other).is_some()
+    }
+
+    /// Computes the union with the given [`Rectangle`].
+    pub fn union(&self, other: &Self) -> Self {
+        let x = self.x.min(other.x);
+        let y = self.y.min(other.y);
+
+        let lower_right_x = (self.x + self.width).max(other.x + other.width);
+        let lower_right_y = (self.y + self.height).max(other.y + other.height);
+
+        let width = lower_right_x - x;
+        let height = lower_right_y - y;
+
+        Rectangle {
+            x,
+            y,
+            width,
+            height,
+        }
+    }
+
     /// Snaps the [`Rectangle`] to __unsigned__ integer coordinates.
     pub fn snap(self) -> Rectangle<u32> {
         Rectangle {
@@ -109,6 +133,16 @@ impl Rectangle<f32> {
             height: self.height as u32,
         }
     }
+
+    /// Expands the [`Rectangle`] a given amount.
+    pub fn expand(self, amount: f32) -> Self {
+        Self {
+            x: self.x - amount,
+            y: self.y - amount,
+            width: self.width + amount * 2.0,
+            height: self.height + amount * 2.0,
+        }
+    }
 }
 
 impl std::ops::Mul<f32> for Rectangle<f32> {

core/src/svg.rs

@@ -7,7 +7,7 @@ use std::path::PathBuf;
 use std::sync::Arc;
 
 /// A handle of Svg data.
-#[derive(Debug, Clone)]
+#[derive(Debug, Clone, PartialEq, Eq)]
 pub struct Handle {
     id: u64,
     data: Arc<Data>,
@@ -57,7 +57,7 @@ impl Hash for Handle {
 }
 
 /// The data of a vectorial image.
-#[derive(Clone, Hash)]
+#[derive(Clone, Hash, PartialEq, Eq)]
 pub enum Data {
     /// File data
     Path(PathBuf),