initial mask impl

src/layout/layer.rs

@@ -1,10 +1,6 @@
 use std::ops::{Index, IndexMut};
 
-use crate::{
-    layout::UiRegion,
-    render::{Primitive, PrimitiveHandle, Primitives},
-    util::Id,
-};
+use crate::render::{MaskIdx, Primitive, PrimitiveHandle, PrimitiveInst, Primitives};
 
 struct LayerNode {
     next: Ptr,
@@ -109,17 +105,11 @@ impl Layers {
         LayerIndexIterator::new(&self.vec, self.last)
     }
 
-    pub fn write<P: Primitive>(
-        &mut self,
-        layer: usize,
-        id: Id,
-        primitive: P,
-        region: UiRegion,
-    ) -> PrimitiveHandle {
-        self[layer].primitives.write(layer, id, primitive, region)
+    pub fn write<P: Primitive>(&mut self, layer: usize, info: PrimitiveInst<P>) -> PrimitiveHandle {
+        self[layer].primitives.write(layer, info)
     }
 
-    pub fn free(&mut self, h: &PrimitiveHandle) {
+    pub fn free(&mut self, h: &PrimitiveHandle) -> MaskIdx {
         self[h.layer].primitives.free(h)
     }
 }