Optimize: add #[inline(always)] to various low-level things

saves up to 20% (text tesselation), and at least 5% overall

epaint/src/color.rs

@@ -100,19 +100,27 @@ impl Color32 {
         Self([l, l, l, 0])
     }
 
+    #[inline(always)]
     pub fn is_opaque(&self) -> bool {
         self.a() == 255
     }
 
+    #[inline(always)]
     pub fn r(&self) -> u8 {
         self.0[0]
     }
+
+    #[inline(always)]
     pub fn g(&self) -> u8 {
         self.0[1]
     }
+
+    #[inline(always)]
     pub fn b(&self) -> u8 {
         self.0[2]
     }
+
+    #[inline(always)]
     pub fn a(&self) -> u8 {
         self.0[3]
     }
@@ -129,11 +137,13 @@ impl Color32 {
     }
 
     /// Premultiplied RGBA
+    #[inline(always)]
     pub fn to_array(&self) -> [u8; 4] {
         [self.r(), self.g(), self.b(), self.a()]
     }
 
     /// Premultiplied RGBA
+    #[inline(always)]
     pub fn to_tuple(&self) -> (u8, u8, u8, u8) {
         (self.r(), self.g(), self.b(), self.a())
     }
@@ -212,6 +222,7 @@ impl Rgba {
     }
 
     /// Multiply with e.g. 0.5 to make us half transparent
+    #[inline(always)]
     pub fn multiply(self, alpha: f32) -> Self {
         Self([
             alpha * self[0],
@@ -221,15 +232,22 @@ impl Rgba {
         ])
     }
 
+    #[inline(always)]
     pub fn r(&self) -> f32 {
         self.0[0]
     }
+
+    #[inline(always)]
     pub fn g(&self) -> f32 {
         self.0[1]
     }
+
+    #[inline(always)]
     pub fn b(&self) -> f32 {
         self.0[2]
     }
+
+    #[inline(always)]
     pub fn a(&self) -> f32 {
         self.0[3]
     }
@@ -258,6 +276,8 @@ impl Rgba {
 
 impl std::ops::Add for Rgba {
     type Output = Rgba;
+
+    #[inline(always)]
     fn add(self, rhs: Rgba) -> Rgba {
         Rgba([
             self[0] + rhs[0],
@@ -270,6 +290,8 @@ impl std::ops::Add for Rgba {
 
 impl std::ops::Mul<Rgba> for Rgba {
     type Output = Rgba;
+
+    #[inline(always)]
     fn mul(self, other: Rgba) -> Rgba {
         Rgba([
             self[0] * other[0],
@@ -282,6 +304,8 @@ impl std::ops::Mul<Rgba> for Rgba {
 
 impl std::ops::Mul<f32> for Rgba {
     type Output = Rgba;
+
+    #[inline(always)]
     fn mul(self, factor: f32) -> Rgba {
         Rgba([
             self[0] * factor,
@@ -294,6 +318,8 @@ impl std::ops::Mul<f32> for Rgba {
 
 impl std::ops::Mul<Rgba> for f32 {
     type Output = Rgba;
+
+    #[inline(always)]
     fn mul(self, rgba: Rgba) -> Rgba {
         Rgba([
             self * rgba[0],

epaint/src/mesh.rs

@@ -92,6 +92,7 @@ impl Mesh {
         }
     }
 
+    #[inline(always)]
     pub fn colored_vertex(&mut self, pos: Pos2, color: Color32) {
         debug_assert!(self.texture_id == TextureId::Egui);
         self.vertices.push(Vertex {
@@ -102,6 +103,7 @@ impl Mesh {
     }
 
     /// Add a triangle.
+    #[inline(always)]
     pub fn add_triangle(&mut self, a: u32, b: u32, c: u32) {
         self.indices.push(a);
         self.indices.push(b);
@@ -110,12 +112,14 @@ impl Mesh {
 
     /// Make room for this many additional triangles (will reserve 3x as many indices).
     /// See also `reserve_vertices`.
+    #[inline(always)]
     pub fn reserve_triangles(&mut self, additional_triangles: usize) {
         self.indices.reserve(3 * additional_triangles);
     }
 
     /// Make room for this many additional vertices.
     /// See also `reserve_triangles`.
+    #[inline(always)]
     pub fn reserve_vertices(&mut self, additional: usize) {
         self.vertices.reserve(additional);
     }
@@ -151,6 +155,7 @@ impl Mesh {
     }
 
     /// Uniformly colored rectangle.
+    #[inline(always)]
     pub fn add_colored_rect(&mut self, rect: Rect, color: Color32) {
         debug_assert!(self.texture_id == TextureId::Egui);
         self.add_rect_with_uv(rect, [WHITE_UV, WHITE_UV].into(), color)

epaint/src/tessellator.rs

@@ -34,10 +34,12 @@ pub struct PathPoint {
 struct Path(Vec<PathPoint>);
 
 impl Path {
+    #[inline(always)]
     pub fn clear(&mut self) {
         self.0.clear();
     }
 
+    #[inline(always)]
     pub fn reserve(&mut self, additional: usize) {
         self.0.reserve(additional)
     }

epaint/src/text/font.rs

@@ -138,10 +138,12 @@ impl FontImpl {
     }
 
     /// Height of one row of text. In points
+    #[inline(always)]
     pub fn row_height(&self) -> f32 {
         self.height_in_points
     }
 
+    #[inline(always)]
     pub fn pixels_per_point(&self) -> f32 {
         self.pixels_per_point
     }
@@ -202,11 +204,13 @@ impl Font {
         slf
     }
 
+    #[inline]
     pub fn round_to_pixel(&self, point: f32) -> f32 {
         (point * self.pixels_per_point).round() / self.pixels_per_point
     }
 
     /// Height of one row of text. In points
+    #[inline(always)]
     pub fn row_height(&self) -> f32 {
         self.row_height
     }