Merge remote-tracking branch 'origin/master' into feat/multi-window-support

# Conflicts:
#	Cargo.toml
#	core/src/window/icon.rs
#	core/src/window/id.rs
#	core/src/window/position.rs
#	core/src/window/settings.rs
#	examples/integration/src/main.rs
#	examples/integration_opengl/src/main.rs
#	glutin/src/application.rs
#	native/src/subscription.rs
#	native/src/window.rs
#	runtime/src/window/action.rs
#	src/lib.rs
#	src/window.rs
#	winit/Cargo.toml
#	winit/src/application.rs
#	winit/src/icon.rs
#	winit/src/settings.rs
#	winit/src/window.rs

1 files changed, 98 insertions, 0 deletions

diff --git a/wgpu/src/layer/mesh.rs b/wgpu/src/layer/mesh.rs
new file mode 100644
index 00000000..7c6206cd
--- /dev/null
+++ b/wgpu/src/layer/mesh.rs
@@ -0,0 +1,98 @@
+//! A collection of triangle primitives.
+use crate::core::{Point, Rectangle};
+use crate::graphics::mesh;
+
+/// A mesh of triangles.
+#[derive(Debug, Clone, Copy)]
+pub enum Mesh<'a> {
+    /// A mesh of triangles with a solid color.
+    Solid {
+        /// The origin of the vertices of the [`Mesh`].
+        origin: Point,
+
+        /// The vertex and index buffers of the [`Mesh`].
+        buffers: &'a mesh::Indexed<mesh::SolidVertex2D>,
+
+        /// The clipping bounds of the [`Mesh`].
+        clip_bounds: Rectangle<f32>,
+    },
+    /// A mesh of triangles with a gradient color.
+    Gradient {
+        /// The origin of the vertices of the [`Mesh`].
+        origin: Point,
+
+        /// The vertex and index buffers of the [`Mesh`].
+        buffers: &'a mesh::Indexed<mesh::GradientVertex2D>,
+
+        /// The clipping bounds of the [`Mesh`].
+        clip_bounds: Rectangle<f32>,
+    },
+}
+
+impl Mesh<'_> {
+    /// Returns the origin of the [`Mesh`].
+    pub fn origin(&self) -> Point {
+        match self {
+            Self::Solid { origin, .. } | Self::Gradient { origin, .. } => {
+                *origin
+            }
+        }
+    }
+
+    /// Returns the indices of the [`Mesh`].
+    pub fn indices(&self) -> &[u32] {
+        match self {
+            Self::Solid { buffers, .. } => &buffers.indices,
+            Self::Gradient { buffers, .. } => &buffers.indices,
+        }
+    }
+
+    /// Returns the clip bounds of the [`Mesh`].
+    pub fn clip_bounds(&self) -> Rectangle<f32> {
+        match self {
+            Self::Solid { clip_bounds, .. }
+            | Self::Gradient { clip_bounds, .. } => *clip_bounds,
+        }
+    }
+}
+
+/// The result of counting the attributes of a set of meshes.
+#[derive(Debug, Clone, Copy, Default)]
+pub struct AttributeCount {
+    /// The total amount of solid vertices.
+    pub solid_vertices: usize,
+
+    /// The total amount of solid meshes.
+    pub solids: usize,
+
+    /// The total amount of gradient vertices.
+    pub gradient_vertices: usize,
+
+    /// The total amount of gradient meshes.
+    pub gradients: usize,
+
+    /// The total amount of indices.
+    pub indices: usize,
+}
+
+/// Returns the number of total vertices & total indices of all [`Mesh`]es.
+pub fn attribute_count_of<'a>(meshes: &'a [Mesh<'a>]) -> AttributeCount {
+    meshes
+        .iter()
+        .fold(AttributeCount::default(), |mut count, mesh| {
+            match mesh {
+                Mesh::Solid { buffers, .. } => {
+                    count.solids += 1;
+                    count.solid_vertices += buffers.vertices.len();
+                    count.indices += buffers.indices.len();
+                }
+                Mesh::Gradient { buffers, .. } => {
+                    count.gradients += 1;
+                    count.gradient_vertices += buffers.vertices.len();
+                    count.indices += buffers.indices.len();
+                }
+            }
+
+            count
+        })
+}