add high-dpi and webp images

svelte/contribute/Area.svelte

@@ -4,7 +4,7 @@
     import Picker from "./Picker";
 
     export let area;
-    export let img;
+    export let images;
     export let steps;
     export let location;
 </script>
@@ -15,7 +15,7 @@
     </title>
 </svelte:head>
 
-<Header {area} {img}>
+<Header {area} {images}>
     <slot />
 </Header>
 

svelte/contribute/Contribute.svelte

@@ -3,12 +3,26 @@
     import Area from "./Area";
     import Landing from "./Landing";
 
-    import imgScreens from "./img/Screens.png";
-    import imgHeads from "./img/Heads.png";
-    import imgIntroduction from "./img/Introduction.png";
-    import imgFoundation from "./img/Foundation.png";
-    import imgDots from "./img/Dots.png";
-    import imgHands from "./img/Hands.png";
+    // this is a little verbose, but dynamic imports aren't SSRed
+    // if we do this in more places, we could write a webpack loader
+    import imgScreensPng from "./img/Screens.png";
+    import imgScreensWebp from "./img/Screens.webp";
+    import imgScreens2xWebp from "./img/Screens@2x.webp";
+    import imgHeadsPng from "./img/Heads.png";
+    import imgHeadsWebp from "./img/Heads.webp";
+    import imgHeads2xWebp from "./img/Heads@2x.webp";
+    import imgIntroductionPng from "./img/Introduction.png";
+    import imgIntroductionWebp from "./img/Introduction.webp";
+    import imgIntroduction2xWebp from "./img/Introduction@2x.webp";
+    import imgFoundationPng from "./img/Foundation.png";
+    import imgFoundationWebp from "./img/Foundation.webp";
+    import imgFoundation2xWebp from "./img/Foundation@2x.webp";
+    import imgDotsPng from "./img/Dots.png";
+    import imgDotsWebp from "./img/Dots.webp";
+    import imgDots2xWebp from "./img/Dots@2x.webp";
+    import imgHandsPng from "./img/Hands.png";
+    import imgHandsWebp from "./img/Hands.webp";
+    import imgHands2xWebp from "./img/Hands@2x.webp";
 
     export let url = "";
     export let locale = "";
@@ -18,7 +32,7 @@
     <Route path="forum" let:location>
         <Area
             area={gettext("Support forum")}
-            img={imgHeads}
+            images={[imgHeadsPng, imgHeadsWebp, imgHeads2xWebp]}
             {location}
             steps={{
                 steps: [
@@ -48,7 +62,11 @@
     <Route path="kb" let:location>
         <Area
             area={gettext("Support articles")}
-            img={imgIntroduction}
+            images={[
+                imgIntroductionPng,
+                imgIntroductionWebp,
+                imgIntroduction2xWebp,
+            ]}
             {location}
             steps={{
                 steps: [
@@ -78,7 +96,7 @@
     <Route path="l10n" let:location>
         <Area
             area={gettext("Localization")}
-            img={imgFoundation}
+            images={[imgFoundationPng, imgFoundationWebp, imgFoundation2xWebp]}
             {location}
             steps={{
                 steps: [
@@ -110,7 +128,7 @@
     <Route path="social" let:location>
         <Area
             area={gettext("Social support")}
-            img={imgDots}
+            images={[imgDotsPng, imgDotsWebp, imgDots2xWebp]}
             {location}
             steps={{
                 steps: [
@@ -140,7 +158,7 @@
     <Route path="play-store" let:location>
         <Area
             area={gettext("Play Store support")}
-            img={imgHands}
+            images={[imgHandsPng, imgHandsWebp, imgHands2xWebp]}
             {location}
             steps={{
                 steps: [
@@ -172,7 +190,7 @@
         </Area>
     </Route>
     <Route path="/">
-        <Landing img={imgScreens} />
+        <Landing images={[imgScreensPng, imgScreensWebp, imgScreens2xWebp]} />
     </Route>
 </Router>
 

svelte/contribute/Header.svelte

@@ -1,8 +1,9 @@
 <script>
     import { Link } from "svelte-navigator";
+    import { srcset } from "../utils";
 
     export let area = "";
-    export let img;
+    export let images;
 </script>
 
 <header>
@@ -25,7 +26,13 @@
 
         <div class="hero">
             <div class="text"><slot /></div>
-            <img src={img} alt="" />
+            <picture>
+                <source
+                    srcset={srcset(images[1], images[2])}
+                    type="image/webp"
+                />
+                <img srcset={srcset(images[0])} src={images[0]} alt="" />
+            </picture>
         </div>
     </div>
 </header>
@@ -54,6 +61,7 @@
         }
 
         .text,
+        picture,
         img {
             flex: 1;
         }

svelte/contribute/Landing.svelte

@@ -1,16 +1,20 @@
 <script>
     import Header from "./Header";
     import Picker from "./Picker";
-    import aboutImg from "./img/About Us.png";
+    import { srcset } from "../utils"
 
-    export let img;
+    import imgAboutPng from "./img/About Us.png";
+    import imgAboutWebp from "./img/About Us.webp";
+    import imgAbout2xWebp from "./img/About Us@2x.webp";
+
+    export let images;
 </script>
 
 <svelte:head>
     <title>{gettext("Contribute")} | {gettext("Mozilla Support")}</title>
 </svelte:head>
 
-<Header {img}>
+<Header {images}>
     <h1>{gettext("Save the world from the comfort of your couch")}</h1>
 
     <p>
@@ -39,10 +43,17 @@
             )}
         </p>
     </div>
-    <img
-        src={aboutImg}
-        alt={gettext("Photo of Mozilla staff and volunteers.")}
-    />
+    <picture>
+        <source
+            srcset={srcset(imgAboutWebp, imgAbout2xWebp)}
+            type="image/webp"
+        />
+        <img
+            srcset={srcset(imgAboutPng)}
+            src={imgAboutPng}
+            alt={gettext("Photo of Mozilla staff and volunteers.")}
+        />
+    </picture>
 </section>
 
 <style lang="scss">
@@ -59,6 +70,7 @@
         }
 
         img,
+        picture,
         .text {
             flex: 1;
         }

svelte/utils.js

@@ -0,0 +1,11 @@
+const staticJinjaTag = "{{ STATIC_URL_WEBPACK }}";
+
+export function srcset(...sources) {
+  return sources
+    .map(
+      (source, index) =>
+        encodeURI(source).replace(encodeURI(staticJinjaTag), staticJinjaTag) +
+        ` ${index + 1}x`
+    )
+    .join(", ");
+}

webpack.common.js

@@ -72,7 +72,7 @@ module.exports = {
         ],
       },
       {
-        test: /\.(svg|png|gif|woff2?)$/,
+        test: /\.(svg|png|webp|gif|woff2?)$/,
         type: "asset/resource",
       },
       // we copy these libraries from external sources, so define their exports here,

webpack.pre-render.js

@@ -47,7 +47,7 @@ module.exports = mergeWithRules({
         },
       },
       {
-        test: /\.(svg|png|gif|woff2?)$/,
+        test: /\.(svg|png|webp|gif|woff2?)$/,
         type: "asset/source",
         use: {
           loader: path.resolve("./webpack/ssr-asset-loader"),