alignment!!!

src/layout/num.rs

@@ -1,20 +1,21 @@
+#[const_trait]
 pub trait UiNum {
     fn to_f32(self) -> f32;
 }
 
-impl UiNum for f32 {
+impl const UiNum for f32 {
     fn to_f32(self) -> f32 {
         self
     }
 }
 
-impl UiNum for u32 {
+impl const UiNum for u32 {
     fn to_f32(self) -> f32 {
         self as f32
     }
 }
 
-impl UiNum for i32 {
+impl const UiNum for i32 {
     fn to_f32(self) -> f32 {
         self as f32
     }

src/layout/orientation.rs

@@ -2,25 +2,6 @@ use std::ops::Not;
 
 use crate::layout::{Vec2, vec2};
 
-#[derive(Clone, Copy, Debug)]
-pub enum Corner {
-    TopLeft,
-    TopRight,
-    BotLeft,
-    BotRight,
-}
-
-impl Corner {
-    pub const fn anchor(&self) -> Vec2 {
-        match self {
-            Corner::TopLeft => vec2(0.0, 0.0),
-            Corner::TopRight => vec2(1.0, 0.0),
-            Corner::BotLeft => vec2(0.0, 1.0),
-            Corner::BotRight => vec2(1.0, 1.0),
-        }
-    }
-}
-
 #[derive(Copy, Clone, Eq, PartialEq)]
 pub enum Axis {
     X,
@@ -89,3 +70,33 @@ impl Vec2 {
         }
     }
 }
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+pub enum Align {
+    TopLeft,
+    Top,
+    TopRight,
+    Left,
+    Center,
+    Right,
+    BotLeft,
+    Bot,
+    BotRight,
+}
+
+impl Align {
+    pub const fn anchor(&self) -> Vec2 {
+        match self {
+            Self::TopLeft => vec2(0.0, 0.0),
+            Self::Top => vec2(0.5, 0.0),
+            Self::TopRight => vec2(1.0, 0.0),
+            Self::Left => vec2(0.0, 0.5),
+            Self::Center => vec2(0.5, 0.5),
+            Self::Right => vec2(1.0, 0.5),
+            Self::BotLeft => vec2(0.0, 1.0),
+            Self::Bot => vec2(0.5, 1.0),
+            Self::BotRight => vec2(1.0, 1.0),
+        }
+    }
+}
+

src/layout/painter.rs

@@ -156,7 +156,7 @@ impl<'a> Painter<'a> {
             .size(&mut self.size_ctx())
     }
 
-    pub fn size_ctx(&mut self) -> SizeCtx {
+    pub fn size_ctx(&mut self) -> SizeCtx<'_> {
         SizeCtx {
             size: self.region().in_size(self.screen_size),
             text: self.text,

src/layout/pos.rs

@@ -1,5 +1,5 @@
 use crate::{
-    layout::{Axis, Corner, Vec2, vec2},
+    layout::{Align, Axis, Vec2},
     util::{F32Util, impl_op},
 };
 
@@ -20,10 +20,6 @@ impl UiPos {
         }
     }
 
-    pub const fn center() -> Self {
-        Self::anchor(vec2(0.5, 0.5))
-    }
-
     pub const fn anchor(anchor: Vec2) -> Self {
         Self {
             anchor,
@@ -38,10 +34,6 @@ impl UiPos {
         }
     }
 
-    pub const fn corner(corner: Corner) -> Self {
-        Self::anchor(corner.anchor())
-    }
-
     pub const fn shift(&mut self, offset: impl const Into<Vec2>) {
         self.offset += offset.into();
     }
@@ -90,6 +82,18 @@ impl UiPos {
     }
 }
 
+impl const From<Align> for UiPos {
+    fn from(align: Align) -> Self {
+        Self::anchor(align.anchor())
+    }
+}
+
+impl Align {
+    pub fn pos(self) -> UiPos {
+        UiPos::from(self)
+    }
+}
+
 #[derive(Clone, Copy, Debug)]
 pub struct UIScalar {
     pub anchor: f32,
@@ -137,8 +141,8 @@ pub struct UiRegion {
 impl UiRegion {
     pub const fn full() -> Self {
         Self {
-            top_left: UiPos::corner(Corner::TopLeft),
-            bot_right: UiPos::corner(Corner::BotRight),
+            top_left: Align::TopLeft.into(),
+            bot_right: Align::BotRight.into(),
         }
     }
     pub fn anchor(anchor: Vec2) -> Self {
@@ -153,9 +157,6 @@ impl UiRegion {
             bot_right: self.bot_right.within(parent),
         }
     }
-    pub fn select(&mut self, inner: &Self) {
-        *self = inner.within(self);
-    }
     pub fn axis_mut(&mut self, axis: Axis) -> UIRegionAxisView<'_> {
         UIRegionAxisView {
             top_left: self.top_left.axis_mut(axis),
@@ -188,12 +189,27 @@ impl UiRegion {
     }
 
     pub fn center(&self) -> UiPos {
-        UiPos::center().within(self)
+        Align::Center.pos().within(self)
     }
 
     pub fn in_size(&self, size: Vec2) -> Vec2 {
         self.bot_right.to_size(size) - self.top_left.to_size(size)
     }
+
+    pub fn select_aligned(&self, size: Vec2, align: Align) -> Self {
+        Self::from_size_align(size, align).within(self)
+    }
+
+    pub fn from_size_align(size: Vec2, align: Align) -> Self {
+        let mut top_left = UiPos::from(align);
+        top_left.offset -= size * align.anchor();
+        let mut bot_right = UiPos::from(align);
+        bot_right.offset += size * (Vec2::ONE - align.anchor());
+        Self {
+            top_left,
+            bot_right,
+        }
+    }
 }
 
 #[derive(Debug)]

src/layout/vec2.rs

@@ -54,9 +54,12 @@ impl Vec2 {
     }
 }
 
-impl const From<f32> for Vec2 {
-    fn from(v: f32) -> Self {
-        Self { x: v, y: v }
+impl<T: const UiNum + Copy> const From<T> for Vec2 {
+    fn from(v: T) -> Self {
+        Self {
+            x: v.to_f32(),
+            y: v.to_f32(),
+        }
     }
 }