From b9651298fc9f5feee59382356f793731b843ea82 Mon Sep 17 00:00:00 2001
From: jtc42 <jtc9242@gmail.com>
Date: Mon, 10 Jun 2019 19:26:40 +0100
Subject: [PATCH] Moved to a single ResizeObserver to manage element resizing

---
 .../viewComponents/streamDisplay.vue          | 215 ++++++++++++++++++
 1 file changed, 215 insertions(+)
 create mode 100644 src/components/viewComponents/streamDisplay.vue

diff --git a/src/components/viewComponents/streamDisplay.vue b/src/components/viewComponents/streamDisplay.vue
new file mode 100644
index 00000000..562ffca4
--- /dev/null
+++ b/src/components/viewComponents/streamDisplay.vue
@@ -0,0 +1,215 @@
+<template>
+	<div ref="streamDisplay" class="stream-display uk-width-1-1 uk-height-1-1 scrollTarget" id="stream-display">
+
+		<img class="uk-align-center uk-margin-remove-bottom" v-on:dblclick="clickmonitor" v-if="showStream" v-bind:src="streamImgUri" alt="Stream">
+
+		<div v-else-if="$store.state.waiting" class="uk-position-center">
+			<div uk-spinner="ratio: 4.5" ></div>
+		</div>
+
+		<div v-else-if="$store.state.globalSettings.disableStream" class="uk-position-center position-relative text-center">
+			Stream preview disabled
+		</div>
+
+		<div v-else class="uk-position-center position-relative text-center">
+			No active connection
+		</div>
+
+	</div>
+</template>
+
+<script>
+import axios from 'axios'
+
+// Export main app
+export default {
+  name: 'stream-display',
+
+  data: function () {
+    return {
+			displaySize: [0, 0],
+			displayPosition: [0, 0],
+			GpuPreviewActive: false,
+			resizeTeimoutId: setTimeout(this.doneResizing, 500)
+    }
+  },
+
+  mounted() {
+
+		const context = this;
+
+    // A global signal listener to change the GPU preview state
+    this.$root.$on('globalTogglePreview', (state) => {
+			console.log(`Toggling preview to ${state}`)
+			this.previewRequest(state)
+		})
+
+		// Mutation observer
+		this.sizeObserver = new ResizeObserver(entries => {
+			context.handleResize()  // For any element attached to the observer, run handleResize() on change
+			entries.forEach(entry => {})  // Optional: Run something per entry
+		});
+
+		// Fetch streamDisplay by ref
+		const streamDisplayElement = this.$refs.streamDisplay.parentNode;
+		// Attach streamDisplay to the size observer
+		this.sizeObserver.observe(streamDisplayElement);
+
+	},
+
+	created: function () {
+
+		// Watch for host 'ready'
+		this.$store.watch(
+			(state)=>{
+				return this.$store.getters.ready
+			},
+			(newValue, oldValue)=>{
+				// 'ready' changed, so do something
+				this.previewRequest(this.$store.state.globalSettings.autoGpuPreview)
+			}
+		)
+	},
+
+	beforeDestroy: function () {
+		// Disconnect the size observer
+		this.sizeObserver.disconnect()
+	},
+
+  methods: {
+    clickmonitor: function(event) {
+			// Calculate steps from event coordinates and store config FOV
+			var xCoordinate = event.offsetX;
+			var yCoordinate = event.offsetY;
+
+			var xRelative = (0.5*event.target.offsetWidth - xCoordinate)/event.target.offsetWidth;
+			var yRelative = (0.5*event.target.offsetHeight - yCoordinate)/event.target.offsetHeight;
+
+			var xSteps = xRelative * this.$store.state.apiConfig.fov[0];
+			var ySteps = yRelative * this.$store.state.apiConfig.fov[1];
+
+			// Emit a signal to move, acted on by panelNavigate.vue
+			this.$root.$emit('globalMoveEvent', xSteps, ySteps, 0, false)
+		},
+		
+		handleResize: function(event) {
+			// Only fires resize event after no resize in 500ms (prevents resize event spam)
+			clearTimeout(this.resizeTeimoutId);
+			this.resizeTeimoutId = setTimeout(this.handleDoneResize, 500)
+		},
+
+		handleDoneResize: function() {
+			// Recalculate size
+			console.log("Recalculating frame size")
+			this.recalculateSize();
+			if (this.$store.state.globalSettings.autoGpuPreview == true && this.GpuPreviewActive == true) {
+				// Reload preview
+				this.$root.$emit('globalTogglePreview', true)
+			}
+		},
+
+		recalculateSize: function () {
+			console.log("Recalculating window dimensions...")
+			// Stacking parentNode is a hacky fix
+			// For some reason, when switching tabs, width was always half what it should be,
+			// until the size was recalculated at some later time. Probably something to do
+			// with tab transition. This parentNode stuff instead reads the size of the tab
+			// container, irrespective of WHICH tab is selected. It's nasty, but works.
+			console.log("ELEMENT:")
+			console.log(this.$refs.streamDisplay)
+			let element = this.$refs.streamDisplay.parentNode.parentNode;
+
+			let size = [element.clientWidth, element.clientHeight];
+
+			let elem_pos = [element.getBoundingClientRect().left, element.getBoundingClientRect().top];
+			let wind_pos = [window.screenX, window.screenY];
+			let navHeight = window.outerHeight - window.innerHeight;
+			let position = [Math.max(0, wind_pos[0] + elem_pos[0]), Math.max(0, wind_pos[1] + elem_pos[1] + navHeight)];
+
+			this.displaySize = size;
+			console.log(`Size: ${this.displaySize}`)
+			this.displayPosition = position;
+			console.log(`Position: ${this.displayPosition}`)
+		},
+
+    previewRequest: function(state) {
+			if (this.$store.getters.ready == true) {
+				// Create URI and set this.GpuPreviewActive depending on if starting or stopping preview
+				if (state == true) {
+					this.GpuPreviewActive = true
+					var requestUri = this.startPreviewUri;
+				}
+				else {
+					this.GpuPreviewActive = false;
+					var requestUri = this.stopPreviewUri;
+				}
+
+				// Generate payload if tracking window position
+				if (this.$store.state.globalSettings.trackWindow == true && state == true) {
+					// Recalculate frame dimensions and position
+					this.recalculateSize()
+					// Copy data into payload array
+					var payload = {
+						window : [
+							this.displayPosition[0],
+							this.displayPosition[1],
+							this.displaySize[0],
+							this.displaySize[1],
+						]
+					}
+				}
+				else {
+					var letpayload = {}
+				}
+
+				// Send preview request
+				axios.post(requestUri, payload)
+				.then(response => { 
+					this.$store.dispatch('updateState');  // Update store state
+				})
+				.catch(error => {
+					this.modalError(error) // Let mixin handle error
+				})
+			}
+    },
+
+  },
+
+  computed: {
+		showStream: function () {
+			return this.$store.getters.ready && !this.$store.state.globalSettings.disableStream
+		},
+    streamImgUri: function () {
+      return this.$store.getters.uri + "/stream"
+		},
+		startPreviewUri: function () {
+			return this.$store.getters.uri + "/camera/preview/start"
+		},
+		stopPreviewUri: function () {
+			return this.$store.getters.uri + "/camera/preview/stop"
+		}
+	}
+
+}
+</script>
+
+<style scoped lang="less">
+.stream-display img {
+	height: 100%;
+	text-align: center;
+	object-fit: contain
+}
+
+.stream-display {
+	width: 100%;
+	height: 100%;
+}
+
+.position-relative {
+	position: relative !important;
+}
+
+.text-center {
+	text-align: center;
+}
+</style>