Independent x/y scaling

Refs khonsulabs/cushy#199

CHANGELOG.md

@@ -23,6 +23,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `Window::winit` now returns an `Arc`-wrapped winit Window.
 - `WindowBehavior::render` no longer returns a `bool`. Closing the window can be
   done through the `RunningWindow` parameter.
+- `DrawableExt::scale` now accepts a parameter that can be an `f32`, 
+  `(f32, f32)`, or `Point<f32>`. This change allows independent scaling of the x
+  and y axis.
 
 ### Added
 

src/drawing.rs

@@ -178,13 +178,13 @@ impl<'render, 'gfx> Renderer<'render, 'gfx> {
         } else {
             None
         };
-        let scale = shape.scale.map_or(1., |scale| {
+        let scale = shape.scale.map_or(Point::squared(1.), |scale| {
             flags |= FLAG_SCALE;
             scale
         });
-        let rotation = shape.rotation.map_or(0., |scale| {
+        let rotation = shape.rotation.map_or(0., |rotation| {
             flags |= FLAG_ROTATE;
-            scale.into_raidans_f()
+            rotation.into_raidans_f()
         });
         if !shape.translation.is_zero() {
             flags |= FLAG_TRANSLATE;
@@ -500,7 +500,7 @@ mod text {
             origin: TextOrigin<Px>,
             translation: Point<Unit>,
             rotation: Option<Angle>,
-            scale: Option<f32>,
+            scale: Option<Point<f32>>,
             opacity: Option<f32>,
         ) where
             Unit: ScreenUnit,
@@ -549,7 +549,7 @@ mod text {
     fn render_one_glyph<Unit>(
         translation: Point<Unit>,
         rotation: Option<Angle>,
-        scale: Option<f32>,
+        scale: Option<Point<f32>>,
         opacity: Option<f32>,
         blit: TextureBlit<Px>,
         cached: &CachedGlyphHandle,
@@ -584,7 +584,7 @@ mod text {
         if cached.is_mask {
             flags |= FLAG_MASKED;
         }
-        let scale = scale.map_or(1., |scale| {
+        let scale = scale.map_or(Point::squared(1.), |scale| {
             flags |= FLAG_SCALE;
             scale
         });

src/lib.rs

@@ -2391,7 +2391,7 @@ pub struct Drawable<T, Unit> {
     /// Rotate the source before rendering.
     pub rotation: Option<Angle>,
     /// Scale the source before rendering.
-    pub scale: Option<f32>,
+    pub scale: Option<Point<f32>>,
     /// An opacity multiplier to apply to this drawable.
     pub opacity: Option<f32>,
 }
@@ -2434,7 +2434,7 @@ pub trait DrawableExt<Source, Unit> {
     /// Rotates `self` by `angle`.
     fn rotate_by(self, angle: Angle) -> Drawable<Source, Unit>;
     /// Scales `self` by `factor`.
-    fn scale(self, factor: f32) -> Drawable<Source, Unit>;
+    fn scale(self, factor: impl ScaleFactor) -> Drawable<Source, Unit>;
     /// Renders this drawable with `opacity`, ranged from 0.- to 1.0.
     fn opacity(self, opacity: f32) -> Drawable<Source, Unit>;
 }
@@ -2450,8 +2450,8 @@ impl<T, Unit> DrawableExt<T, Unit> for Drawable<T, Unit> {
         self
     }
 
-    fn scale(mut self, factor: f32) -> Drawable<T, Unit> {
-        self.scale = Some(factor);
+    fn scale(mut self, factor: impl ScaleFactor) -> Drawable<T, Unit> {
+        self.scale = Some(factor.into_scaling_vector());
         self
     }
 
@@ -2461,6 +2461,30 @@ impl<T, Unit> DrawableExt<T, Unit> for Drawable<T, Unit> {
     }
 }
 
+/// A type representing an x and y scaling factor.
+pub trait ScaleFactor {
+    /// Returns a `Point` with an x and y scaling factor from `self`.
+    fn into_scaling_vector(self) -> Point<f32>;
+}
+
+impl ScaleFactor for f32 {
+    fn into_scaling_vector(self) -> Point<f32> {
+        Point::squared(self)
+    }
+}
+
+impl ScaleFactor for (f32, f32) {
+    fn into_scaling_vector(self) -> Point<f32> {
+        Point::new(self.0, self.1)
+    }
+}
+
+impl ScaleFactor for Point<f32> {
+    fn into_scaling_vector(self) -> Point<f32> {
+        self
+    }
+}
+
 impl<T, Unit> DrawableExt<T, Unit> for T
 where
     Drawable<T, Unit>: From<T>,
@@ -2474,7 +2498,7 @@ where
         Drawable::from(self).rotate_by(angle)
     }
 
-    fn scale(self, factor: f32) -> Drawable<T, Unit> {
+    fn scale(self, factor: impl ScaleFactor) -> Drawable<T, Unit> {
         Drawable::from(self).scale(factor)
     }
 

src/pipeline.rs

@@ -73,7 +73,7 @@ pub(crate) const FLAG_MASKED: u32 = 1 << 5;
 #[repr(C)]
 pub(crate) struct PushConstants {
     pub flags: u32,
-    pub scale: f32,
+    pub scale: Point<f32>,
     pub rotation: f32,
     pub opacity: f32,
     pub translation: Point<i32>,
@@ -146,7 +146,7 @@ where
                     flags |= FLAG_MASKED;
                 }
             }
-            let scale = self.scale.map_or(1., |scale| {
+            let scale = self.scale.map_or(Point::squared(1.), |scale| {
                 flags |= FLAG_SCALE;
                 scale
             });

src/shader.wgsl

@@ -1,6 +1,7 @@
 struct PushConstants {
     flags: i32,
-    scale: f32,
+    scale_x: f32,
+    scale_y: f32,
     rotation: f32,
     opacity: f32,
     translation_x: i32,
@@ -90,7 +91,7 @@ fn vertex(input: VertexInput) -> VertexOutput {
         position = position * mat2x2<f32>(angle_cos, -angle_sin, angle_sin, angle_cos);
     }
     if (flags & flag_scale) != u32(0) {
-        position = position * pc.scale;
+        position = position * vec2<f32>(pc.scale_x, pc.scale_y);
     }
     if (flags & flag_translate) != u32(0) {
         position = position + vec2<f32>(