feat: Add preview screen before encoding

src/assets/css/2-components/_buttons.css

@@ -56,6 +56,45 @@
   background: var(--btn-primary);
 }
 
+/* Loading state
+-------------------------------------------------------------- */
+
+.btn--loading,
+.btn--loading:link,
+.btn--loading:visited {
+  position: relative;
+  color: transparent;
+  pointer-events: none;
+}
+
+.btn--loading svg {
+  display: none;
+}
+
+.btn--loading::after {
+  position: absolute;
+  top: calc(50% - (2em / 2));
+  left: calc(50% - (2em / 2));
+  display: block;
+  width: 2em;
+  height: 2em;
+  border: .2rem solid transparent;
+  border-color: transparent transparent #fff #fff;
+  border-radius: 42rem;
+  content: "";
+  animation: spinAround 500ms infinite linear;
+}
+
+@keyframes spinAround {
+  0% {
+    transform: rotate(0deg);
+  }
+  100% {
+    transform: rotate(359deg);
+  }
+}
+
+
 /* size
 -------------------------------------------------------------- */
 

src/assets/css/4-modules/encoding.css

@@ -6,6 +6,7 @@
   position: fixed;
   top: 0;
   left: 0;
+  z-index: 1;
   display: flex;
   flex-direction: column;
   justify-content: center;

src/assets/css/7-rwd/_rwd-landscape.css

@@ -47,6 +47,7 @@
     flex-direction: row;
     margin-top: auto;
     margin-bottom: auto;
+    padding-left: 2rem;
   }
 
   .capture-progress {
@@ -105,12 +106,13 @@
   .download {
     flex-direction: row;
     align-items: center;
+    padding-right: 2rem;
   }
 
   .download-btn,
   .download-btn:visited {
     margin: auto 0;
-    margin-right: 2rem;
+    margin-right: auto;
     margin-left: auto;
     width: auto;
   }

src/router.js

@@ -3,6 +3,7 @@ import VueRouter from 'vue-router'
 
 import Welcome from '/views/screens/welcome'
 import Capture from '/views/screens/capture'
+import Preview from '/views/screens/preview'
 import Download from '/views/screens/download'
 
 Vue.use(VueRouter)
@@ -12,6 +13,7 @@ export default new VueRouter({
   routes: [
     { name: 'home', path: '/', component: Welcome },
     { name: 'capture', path: '/capture', component: Capture },
+    { name: 'preview', path: '/preview', component: Preview },
     { name: 'download', path: '/download', component: Download }
   ]
 })

src/views/screens/capture.vue

@@ -9,18 +9,14 @@
       <video ref="preview" class="preview-visual" :class="{ 'preview--flip': shouldFlip }" preload="yes" autoplay muted playsinline webkit-playsinline></video>
     </div>
 
-    <button class="capture-btn" :class="{ 'capture-btn--capturing': capturing }" :disabled="!camera || encoding" @click.prevent="startCapturing">Capture</button>
-
-    <encoding-overlay v-if="encoding" :value="encodingProgress"></encoding-overlay>
+    <button class="capture-btn" :class="{ 'capture-btn--capturing': capturing }" :disabled="!camera" @click.prevent="startCapturing">Capture</button>
   </div>
 </template>
 
 <script>
 import captureOptions from '/views/components/capture-options'
 import captureProgress from '/views/components/capture-progress'
-import encodingOverlay from '/views/components/encoding'
 import { capture } from '/services/capture.js'
-import { encode } from '/services/encode.js'
 
 import 'objectFitPolyfill'
 
@@ -30,14 +26,11 @@ export default {
   name: 'capture',
   components: {
     captureOptions,
-    captureProgress,
-    encodingOverlay
+    captureProgress
   },
   data: () => ({
     capturing: false,
-    capturingProgress: 0,
-    encoding: false,
-    encodingProgress: 0
+    capturingProgress: 0
   }),
   computed: {
     ...mapState([
@@ -82,28 +75,8 @@ export default {
         this.capturing = false
         this.capturingProgress = 0
         this.$store.commit('updateCapture', captureData)
-        this.startEncoding()
-      })
-    },
-    startEncoding () {
-      this.encoding = true
-      const encoding = encode(this.capture)
-
-      encoding.once('error', error => {
-        console.error(error)
-        this.encoding = false
-        this.encodingProgress = 0
-      })
-
-      encoding.on('progress', value => {
-        this.encodingProgress = value
-      })
-
-      encoding.once('done', gif => {
-        this.encoding = false
-        this.encodingProgress = 0
-        this.$store.commit('updateGif', gif)
-        this.$router.push({ name: 'download' })
+        this.$router.push({ name: 'preview' })
+        // this.startEncoding()
       })
     },
     async ensureCamera () {

src/views/screens/download.vue

@@ -26,7 +26,10 @@ export default {
       'gif'
     ]),
     timestamp () {
-      return this.gif.createdAt.getTime()
+      if (this.gif) {
+        return this.gif.createdAt.getTime()
+      }
+      return null
     }
   },
   methods: {
@@ -37,9 +40,9 @@ export default {
   created () {
     if (!this.gif) {
       this.$router.push({ name: 'home' })
+    } else {
+      this.objectUrl = URL.createObjectURL(this.gif.blob)
     }
-
-    this.objectUrl = URL.createObjectURL(this.gif.blob)
   },
   destroyed () {
     URL.revokeObjectURL(this.objectUrl)

src/views/screens/preview.vue

@@ -0,0 +1,103 @@
+<template lang="html">
+  <div class="download">
+    <div class="options">
+      <span></span>
+      <button class="options__btn" @click="back">← back</button>
+    </div>
+
+    <div class="preview">
+      <canvas ref="previewCanvas" class="preview-visual"></canvas>
+    </div>
+
+    <button class="download-btn btn btn--primary w100" :class="{ 'btn--loading': encoding }" :disabled="encoding" @click="startEncoding">Generate GIF</button>
+
+    <encoding-overlay v-if="encoding" :value="encodingProgress"></encoding-overlay>
+  </div>
+</template>
+
+<script>
+import { encode } from '/services/encode.js'
+import encodingOverlay from '/views/components/encoding'
+
+import { mapState } from 'vuex'
+
+export default {
+  name: 'preview',
+  components: {
+    encodingOverlay
+  },
+  data: () => ({
+    encoding: false,
+    encodingProgress: 0,
+    previewTimeout: null
+  }),
+  computed: {
+    ...mapState([
+      'camera',
+      'capture'
+    ])
+  },
+  methods: {
+    back () {
+      this.$router.push({ name: 'capture' })
+    },
+    backHome () {
+      this.$router.push({ name: 'home' })
+    },
+    printPreview (context, frameNumber) {
+      this.previewTimeout = setTimeout(() => {
+        // Looper
+        frameNumber < (this.capture.imageDataList.length - 1) ? frameNumber++ : frameNumber = 0
+        // Printer
+        const image = this.capture.imageDataList[frameNumber]
+        context.putImageData(image, 0, 0)
+        this.printPreview(context, frameNumber)
+      }, this.capture.delayTime)
+    },
+    startPreview () {
+      if (!this.capture) {
+        this.backHome()
+      } else {
+        const canvas = this.$refs.previewCanvas
+        canvas.width = this.capture.imageWidth
+        canvas.height = this.capture.imageHeight
+        const canvasContext = canvas.getContext('2d')
+
+        this.printPreview(canvasContext, 0)
+      }
+    },
+    startEncoding () {
+      this.encoding = true
+      const encoding = encode(this.capture)
+
+      encoding.once('error', error => {
+        console.error(error)
+        this.encoding = false
+        this.encodingProgress = 0
+      })
+
+      encoding.on('progress', value => {
+        this.encodingProgress = value
+      })
+
+      encoding.once('done', gif => {
+        this.encoding = false
+        this.encodingProgress = 0
+        this.$store.commit('updateGif', gif)
+        this.$router.push({ name: 'download' })
+      })
+    }
+  },
+  created () {
+    if (!this.capture) {
+      this.backHome()
+    }
+  },
+  mounted () {
+    this.startPreview()
+  },
+  destroyed () {
+    window.clearTimeout(this.previewTimeout)
+  }
+}
+</script>