Initialize wgpu

We only enable the `vulkan` feature for now.

Cargo.toml

@@ -22,6 +22,9 @@ members = [
     "examples/tour",
 ]
 
+[features]
+vulkan = ["iced_wgpu/vulkan"]
+
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 iced_winit = { version = "0.1.0-alpha", path = "winit" }
 iced_wgpu = { version = "0.1.0-alpha", path = "wgpu" }

src/lib.rs

@@ -32,6 +32,8 @@ pub trait UserInterface {
             .build(&event_loop)
             .expect("Open window");
 
+        let renderer = Renderer::new(&window);
+
         event_loop.run(move |event, _, control_flow| match event {
             Event::EventsCleared => {
                 window.request_redraw();

wgpu/Cargo.toml

@@ -7,6 +7,10 @@ description = "A wgpu renderer for Iced"
 license = "MIT"
 repository = "https://github.com/hecrj/iced"
 
+[features]
+vulkan = ["wgpu/vulkan"]
+
 [dependencies]
 iced_native = { version = "0.1.0-alpha", path = "../native" }
 wgpu = "0.3"
+raw-window-handle = "0.1"

wgpu/src/lib.rs

@@ -4,7 +4,44 @@ use iced_native::{
     Style, Text,
 };
 
-pub struct Renderer;
+use raw_window_handle::HasRawWindowHandle;
+use wgpu::{
+    Adapter, Device, DeviceDescriptor, Extensions, Instance, Limits,
+    PowerPreference, RequestAdapterOptions, Surface,
+};
+
+pub struct Renderer {
+    instance: Instance,
+    surface: Surface,
+    adapter: Adapter,
+    device: Device,
+}
+
+impl Renderer {
+    pub fn new<W: HasRawWindowHandle>(window: &W) -> Self {
+        let instance = Instance::new();
+
+        let adapter = instance.request_adapter(&RequestAdapterOptions {
+            power_preference: PowerPreference::LowPower,
+        });
+
+        let device = adapter.request_device(&DeviceDescriptor {
+            extensions: Extensions {
+                anisotropic_filtering: false,
+            },
+            limits: Limits { max_bind_groups: 1 },
+        });
+
+        let surface = instance.create_surface(window.raw_window_handle());
+
+        Self {
+            instance,
+            surface,
+            adapter,
+            device,
+        }
+    }
+}
 
 impl text::Renderer for Renderer {
     fn node(&self, _text: &Text) -> Node {