Screenshot WIP for feedback

index.html

@@ -33,11 +33,15 @@
                 brush
                 if-no-vr-headset="visible: false"
                 paint-controls="hand: left"
+                screenshot-camera
+                trigger-mode="brush"
                 ui></a-entity>
       <a-entity id="right-hand"
                 brush
                 if-no-vr-headset="visible: false"
                 paint-controls="hand: right"
+                screenshot-camera
+                trigger-mode="brush"
                 ui></a-entity>
       <a-entity id="ground"
                 geometry="primitive: circle; radius: 12;"

src/components/brush.js

@@ -28,6 +28,9 @@ AFRAME.registerComponent('brush', {
 
     var self = this;
 
+    this.el.addEventListener('trigger-mode-changed', this.triggerModeChanged.bind(this));
+    this.triggerModeChanged();
+
     this.el.addEventListener('axismove', function (evt) {
       if (evt.detail.axis[0] === 0 && evt.detail.axis[1] === 0) {
         return;
@@ -37,15 +40,15 @@ AFRAME.registerComponent('brush', {
     });
 
     this.el.addEventListener('buttondown', function (evt) {
-      if (!self.data.enabled) { return; }
+      if (!self.enabled) { return; }
       // Grip
       if (evt.detail.id === 2) {
         self.system.undo();
       }
     });
 
     this.el.addEventListener('buttonchanged', function (evt) {
-      if (!self.data.enabled) { return; }
+      if (!self.enabled) { return; }
       // Trigger
       if (evt.detail.id === 1) {
         var value = evt.detail.state.value;
@@ -65,7 +68,14 @@ AFRAME.registerComponent('brush', {
       }
     });
   },
+
+  triggerModeChanged:  function() {
+    this.enabled = this.data.enabled && this.el.getAttribute('trigger-mode') == 'brush'
+  },
+
   update: function (oldData) {
+    this.triggerModeChanged();
+
     var data = this.data;
     if (oldData.color !== data.color) {
       this.color.set(data.color);

src/components/screenshot-camera.js

@@ -0,0 +1,113 @@
+/* globals AFRAME THREE */
+AFRAME.registerComponent('screenshot-camera', {
+  schema: {
+    width: {default: 1024, min: 1, max: 2048},
+    height: {default: 768, min: 1, max: 1516},
+  },
+  init: function () {
+    var data = this.data;
+    var width = data.width;
+    var height = data.height;
+    this.sceneEl = document.querySelector('a-scene');
+    this.scene = this.sceneEl.object3D
+
+    this.renderTarget = new THREE.WebGLRenderTarget(width, height, {
+      format: THREE.RGBAFormat,
+      type: THREE.UnsignedByteType,
+    })
+
+    var ratio = width / height;
+    this.camera = new THREE.PerspectiveCamera(55, ratio, 0.01, 1000 );
+    this.camera.rotation.x = Math.PI / 2
+    this.camera.rotation.y = Math.PI
+    this.camera.rotation.z = Math.PI
+    this.screen = new THREE.Mesh(
+      new THREE.PlaneBufferGeometry(ratio * 0.2, 0.2),
+      new THREE.MeshBasicMaterial({
+        side: THREE.DoubleSide,
+        map: this.renderTarget
+      })
+    )
+    this.screen.rotation.set(3 * Math.PI / 2, 0, 0)
+    this.screen.position.set(0.2, 0, -0.2)
+    this.el.object3D.add(this.screen)
+    this.el.object3D.add(this.camera)
+
+    this.el.addEventListener('trigger-mode-changed', this.triggerModeChanged.bind(this))
+    this.triggerModeChanged();
+    this.canTakePicture = true
+    this.el.addEventListener('triggerchanged', function (evt) {
+      if (!this.enabled) {
+        return
+      }
+
+      if (evt.detail.value == 1 && this.canTakePicture) {
+        this.saveNextTick = true
+        this.canTakePicture = false
+      } else if (evt.detail.value < 1) {
+        this.canTakePicture = true
+      }
+    }.bind(this));
+
+    this.canvas = document.createElement('canvas')
+    this.canvas.width = width
+    this.canvas.height = height
+  },
+
+  triggerModeChanged: function() {
+    this.enabled = this.el.getAttribute('trigger-mode') == 'camera'
+    this.screen.visible = this.enabled
+  },
+
+  tick: function(time, timeDelta) {
+    if (!this.enabled) return
+    this.sceneEl.renderer.render(this.scene, this.camera, this.renderTarget, true)
+    if (this.saveNextTick) {
+      this.saveCapture();
+      this.saveNextTick = false;
+    }
+  },
+
+  saveCapture: function () {
+    var width = this.data.width
+    var height = this.data.height
+    this.pixels = new Uint8Array(4 * width * height)
+    var renderer = this.sceneEl.renderer
+
+    var _gl = renderer.context
+    var framebuffer = renderer.properties.get(this.renderTarget).__webglFramebuffer
+    _gl.bindFramebuffer( _gl.FRAMEBUFFER, framebuffer );
+    _gl.readPixels( 0, 0, width, height, _gl.RGBA,_gl.UNSIGNED_BYTE,  this.pixels );
+    this.pixels = this.flipPixelsVertically(this.pixels, width, height)
+
+    this.imageData = new ImageData(new Uint8ClampedArray(this.pixels), width, height)
+    this.canvas.getContext('2d').putImageData(this.imageData, 0, 0)
+    this.canvas.toBlob(function (blob) {
+      var url = URL.createObjectURL(blob);
+      var fileName = 'screenshot-' + document.title + '-' + Date.now() + '.png';
+      var aEl = document.createElement('a');
+      aEl.href = url;
+      aEl.setAttribute('download', fileName);
+      aEl.innerHTML = 'downloading...';
+      aEl.style.display = 'none';
+      document.body.appendChild(aEl);
+      setTimeout(function () {
+        aEl.click();
+        document.body.removeChild(aEl);
+      }, 1);
+    }, 'image/png');
+  },
+
+  flipPixelsVertically: function (pixels, width, height) {
+    var flippedPixels = pixels.slice(0);
+    for (var x = 0; x < width; ++x) {
+      for (var y = 0; y < height; ++y) {
+        flippedPixels[x * 4 + y * width * 4] = pixels[x * 4 + (height - y) * width * 4];
+        flippedPixels[x * 4 + 1 + y * width * 4] = pixels[x * 4 + 1 + (height - y) * width * 4];
+        flippedPixels[x * 4 + 2 + y * width * 4] = pixels[x * 4 + 2 + (height - y) * width * 4];
+        flippedPixels[x * 4 + 3 + y * width * 4] = pixels[x * 4 + 3 + (height - y) * width * 4];
+      }
+    }
+    return flippedPixels;
+  },
+});

src/components/ui.js

@@ -156,6 +156,7 @@ AFRAME.registerComponent('ui', {
       }
       case name === 'clear': {
         if (!this.pressedObjects[name]) {
+          this.toggleCaptureCamera();
           this.el.sceneEl.systems.brush.clear();
         }
         break;
@@ -355,6 +356,12 @@ AFRAME.registerComponent('ui', {
     this.handEl.setAttribute('brush', 'size', brushSize);
   },
 
+  toggleCaptureCamera: function() {
+    var enableCamera = this.handEl.getAttribute('trigger-mode') != 'camera'
+    this.handEl.setAttribute('trigger-mode', enableCamera ? 'camera' : 'brush')
+    this.handEl.emit('trigger-mode-changed')
+  },
+
   handleHover: function () {
     this.updateHoverObjects();
     this.updateMaterials();

src/index.js

@@ -19,6 +19,7 @@ require('./components/line.js');
 require('./components/look-controls-alt.js');
 require('./components/orbit-controls.js');
 require('./components/paint-controls.js');
+require('./components/screenshot-camera.js');
 require('./components/ui.js');
 require('./components/ui-raycaster.js');