1 files changed, 40 insertions, 0 deletions
diff --git a/src/transform.rs b/src/transform.rs
index 0b65728..ccb1850 100644
--- a/src/transform.rs
+++ b/src/transform.rs
@@ -39,3 +39,43 @@ impl Sample for Translate {
         self.inner.sample(x - self.offset.0, y - self.offset.1)
     }
 }
+
+pub enum CompositeOperation {
+    Add,
+    Subtract,
+    Multiply,
+    Mix(f64),
+}
+pub struct Composite {
+    pub a: Box<dyn Sample>,
+    pub b: Box<dyn Sample>,
+    pub mode: CompositeOperation,
+}
+impl Sample for Composite {
+    fn sample(&mut self, x: f64, y: f64) -> Color {
+        let a = self.a.sample(x, y);
+        let b = self.b.sample(x, y);
+        match self.mode {
+            CompositeOperation::Add => Color {
+                r: a.r + b.r,
+                g: a.g + b.g,
+                b: a.b + b.b,
+            },
+            CompositeOperation::Subtract => Color {
+                r: a.r - b.r,
+                g: a.g - b.g,
+                b: a.b - b.b,
+            },
+            CompositeOperation::Multiply => Color {
+                r: a.r * b.r,
+                g: a.g * b.g,
+                b: a.b * b.b,
+            },
+            CompositeOperation::Mix(f) => Color {
+                r: a.r * (1.0 - f) + b.r * f,
+                g: a.g * (1.0 - f) + b.g * f,
+                b: a.b * (1.0 - f) + b.b * f,
+            },
+        }
+    }
+}