center anchors on 0 0

src/render/primitive/format.rs

@@ -1,7 +1,7 @@
-use crate::primitive::{point::point, Point};
+use crate::primitive::{Point, point::point};
 
 #[repr(C)]
-#[derive(Copy, Clone, bytemuck::Pod, bytemuck::Zeroable, Default)]
+#[derive(Debug, Copy, Clone, bytemuck::Pod, bytemuck::Zeroable, Default)]
 pub struct UIPos {
     pub anchor: Point,
     pub offset: Point,
@@ -16,7 +16,7 @@ impl UIPos {
     }
 
     pub const fn top_left() -> Self {
-        Self::anchor_offset(0.0, 0.0, 0.0, 0.0)
+        Self::anchor_offset(-1.0, -1.0, 0.0, 0.0)
     }
 
     pub const fn bottom_right() -> Self {
@@ -24,15 +24,14 @@ impl UIPos {
     }
 
     pub const fn within(&self, region: &UIRegion) -> UIPos {
-        let range = region.bot_right.anchor - region.top_left.anchor;
-        let region_offset = region
-            .top_left
-            .offset
-            .lerp(region.bot_right.offset, self.anchor);
-        UIPos {
-            anchor: region.top_left.anchor + self.anchor * range,
-            offset: self.offset + region_offset,
-        }
+        let lerp = self.anchor_01();
+        let anchor = region.top_left.anchor.lerp(region.bot_right.anchor, lerp);
+        let offset = self.offset + region.top_left.offset.lerp(region.bot_right.offset, lerp);
+        UIPos { anchor, offset }
+    }
+
+    pub const fn anchor_01(&self) -> Point {
+        (self.anchor + 1.0) / 2.0
     }
 
     pub fn axis_mut(&mut self, axis: Axis) -> UIPosAxisView<'_> {