--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/Platforms/Wasm/wasm-viewport.ts	Tue Jun 19 16:06:32 2018 +0200
@@ -0,0 +1,269 @@
+var isPendingRedraw = false;
+
+function ScheduleWebViewportRedraw(cppViewportHandle: any) : void
+{
+  if (!isPendingRedraw) {
+    isPendingRedraw = true;
+    console.log('Scheduling a refresh of the viewport, as its content changed');
+    window.requestAnimationFrame(function() {
+      isPendingRedraw = false;
+      Stone.WasmViewport.GetFromCppViewport(cppViewportHandle).Redraw();
+    });
+  }
+}
+
+declare function UTF8ToString(any): string;
+
+function CreateWasmViewport(htmlCanvasId: string) : any {
+  var cppViewportHandle = CreateCppViewport();
+  var canvasId = UTF8ToString(htmlCanvasId);
+  var webViewport = new Stone.WasmViewport(StoneFrameworkModule, canvasId, cppViewportHandle);  // viewports are stored in a static map in WasmViewport -> won't be deleted
+  webViewport.Initialize();
+
+  return cppViewportHandle;
+}
+
+module Stone {
+  
+//  export declare type InitializationCallback = () => void;
+  
+//  export declare var StoneFrameworkModule : any;
+  
+  //const ASSETS_FOLDER : string = "assets/lib";
+  //const WASM_FILENAME : string = "orthanc-framework";
+
+  export class WasmViewport {
+
+    private static cppWebViewportsMaps_ : Map<number, WasmViewport> = new Map<number, WasmViewport>();
+
+    private module_ : any;
+    private canvasId_ : string;
+    private htmlCanvas_ : HTMLCanvasElement;
+    private context_ : CanvasRenderingContext2D;
+    private imageData_ : any = null;
+    private renderingBuffer_ : any = null;
+    private touchZoom_ : any = false;
+    private touchTranslation_ : any = false;
+
+    private ViewportSetSize : Function;
+    private ViewportRender : Function;
+    private ViewportMouseDown : Function;
+    private ViewportMouseMove : Function;
+    private ViewportMouseUp : Function;
+    private ViewportMouseEnter : Function;
+    private ViewportMouseLeave : Function;
+    private ViewportMouseWheel : Function;
+    private ViewportKeyPressed : Function;
+
+    private pimpl_ : any; // Private pointer to the underlying WebAssembly C++ object
+
+    public constructor(module: any, canvasId: string, cppViewport: any) {
+      
+      this.pimpl_ = cppViewport;
+      WasmViewport.cppWebViewportsMaps_[this.pimpl_] = this;
+
+      this.module_ = module;
+      this.canvasId_ = canvasId;
+      this.htmlCanvas_ = document.getElementById(this.canvasId_) as HTMLCanvasElement;
+      this.context_ = this.htmlCanvas_.getContext('2d');
+
+      this.ViewportSetSize = this.module_.cwrap('ViewportSetSize', null, [ 'number', 'number', 'number' ]);
+      this.ViewportRender = this.module_.cwrap('ViewportRender', null, [ 'number', 'number', 'number', 'number' ]);
+      this.ViewportMouseDown = this.module_.cwrap('ViewportMouseDown', null, [ 'number', 'number', 'number', 'number', 'number' ]);
+      this.ViewportMouseMove = this.module_.cwrap('ViewportMouseMove', null, [ 'number', 'number', 'number' ]);
+      this.ViewportMouseUp = this.module_.cwrap('ViewportMouseUp', null, [ 'number' ]);
+      this.ViewportMouseEnter = this.module_.cwrap('ViewportMouseEnter', null, [ 'number' ]);
+      this.ViewportMouseLeave = this.module_.cwrap('ViewportMouseLeave', null, [ 'number' ]);
+      this.ViewportMouseWheel = this.module_.cwrap('ViewportMouseWheel', null, [ 'number', 'number', 'number', 'number', 'number' ]);
+      this.ViewportKeyPressed = this.module_.cwrap('ViewportKeyPressed', null, [ 'number', 'string', 'number', 'number' ]);
+    }
+
+    public GetCppViewport() : number {
+      return this.pimpl_;
+    }
+
+    public static GetFromCppViewport(cppViewportHandle: number) : WasmViewport {
+      if (WasmViewport.cppWebViewportsMaps_[cppViewportHandle] !== undefined) {
+        return WasmViewport.cppWebViewportsMaps_[cppViewportHandle];
+      }
+      console.log("WasmViewport not found !");
+      return undefined;
+    }
+
+    public Redraw() {
+      if (this.imageData_ === null ||
+          this.renderingBuffer_ === null ||
+          this.ViewportRender(this.pimpl_,
+                         this.imageData_.width,
+                         this.imageData_.height,
+                         this.renderingBuffer_) == 0) {
+        console.log('The rendering has failed');
+      } else {
+        // Create an accessor to the rendering buffer (i.e. create a
+        // "window" above the heap of the WASM module), then copy it to
+        // the ImageData object
+        this.imageData_.data.set(new Uint8ClampedArray(
+          this.module_.buffer,
+          this.renderingBuffer_,
+          this.imageData_.width * this.imageData_.height * 4));
+        
+        this.context_.putImageData(this.imageData_, 0, 0);
+      }
+    }
+  
+    public Resize() {
+      if (this.imageData_ != null &&
+          (this.imageData_.width != window.innerWidth ||
+           this.imageData_.height != window.innerHeight)) {
+        this.imageData_ = null;
+      }
+      
+      // width/height can be defined in percent of window width/height through html attributes like data-width-ratio="50" and data-height-ratio="20"
+      var widthRatio = Number(this.htmlCanvas_.dataset["widthRatio"]) || 100;
+      var heightRatio = Number(this.htmlCanvas_.dataset["heightRatio"]) || 100;
+
+      this.htmlCanvas_.width = window.innerWidth * (widthRatio / 100);  
+      this.htmlCanvas_.height = window.innerHeight * (heightRatio / 100);
+
+      console.log("resizing WasmViewport: ", this.htmlCanvas_.width, "x", this.htmlCanvas_.height);
+
+      if (this.imageData_ === null) {
+        this.imageData_ = this.context_.getImageData(0, 0, this.htmlCanvas_.width, this.htmlCanvas_.height);
+        this.ViewportSetSize(this.pimpl_, this.htmlCanvas_.width, this.htmlCanvas_.height);
+  
+        if (this.renderingBuffer_ != null) {
+          this.module_._free(this.renderingBuffer_);
+        }
+        
+        this.renderingBuffer_ = this.module_._malloc(this.imageData_.width * this.imageData_.height * 4);
+      }
+      
+      this.Redraw();
+    }
+
+    public Initialize() {
+      
+      // Force the rendering of the viewport for the first time
+      this.Resize();
+    
+      var that : WasmViewport = this;
+      // Register an event listener to call the Resize() function 
+      // each time the window is resized.
+      window.addEventListener('resize', function(event) {
+        that.Resize();
+      }, false);
+  
+      this.htmlCanvas_.addEventListener('contextmenu', function(event) {
+        // Prevent right click on the canvas
+        event.preventDefault();
+      }, false);
+      
+      this.htmlCanvas_.addEventListener('mouseleave', function(event) {
+        that.ViewportMouseLeave(that.pimpl_);
+      });
+      
+      this.htmlCanvas_.addEventListener('mouseenter', function(event) {
+        that.ViewportMouseEnter(that.pimpl_);
+      });
+    
+      this.htmlCanvas_.addEventListener('mousedown', function(event) {
+        var x = event.pageX - this.offsetLeft;
+        var y = event.pageY - this.offsetTop;
+        that.ViewportMouseDown(that.pimpl_, event.button, x, y, 0 /* TODO */);    
+      });
+    
+      this.htmlCanvas_.addEventListener('mousemove', function(event) {
+        var x = event.pageX - this.offsetLeft;
+        var y = event.pageY - this.offsetTop;
+        that.ViewportMouseMove(that.pimpl_, x, y);
+      });
+    
+      this.htmlCanvas_.addEventListener('mouseup', function(event) {
+        that.ViewportMouseUp(that.pimpl_);
+      });
+    
+      window.addEventListener('keydown', function(event) {
+        that.ViewportKeyPressed(that.pimpl_, event.key, event.shiftKey, event.ctrlKey, event.altKey);
+      });
+    
+      this.htmlCanvas_.addEventListener('wheel', function(event) {
+        var x = event.pageX - this.offsetLeft;
+        var y = event.pageY - this.offsetTop;
+        that.ViewportMouseWheel(that.pimpl_, event.deltaY, x, y, event.ctrlKey);
+        event.preventDefault();
+      });
+
+      this.htmlCanvas_.addEventListener('touchstart', function(event) {
+        that.ResetTouch();
+      });
+    
+      this.htmlCanvas_.addEventListener('touchend', function(event) {
+        that.ResetTouch();
+      });
+    
+      this.htmlCanvas_.addEventListener('touchmove', function(event) {
+        if (that.touchTranslation_.length == 2) {
+          var t = that.GetTouchTranslation(event);
+          that.ViewportMouseMove(that.pimpl_, t[0], t[1]);
+        }
+        else if (that.touchZoom_.length == 3) {
+          var z0 = that.touchZoom_;
+          var z1 = that.GetTouchZoom(event);
+          that.ViewportMouseMove(that.pimpl_, z0[0], z0[1] - z0[2] + z1[2]);
+        }
+        else {
+          // Realize the gesture event
+          if (event.targetTouches.length == 1) {
+            // Exactly one finger inside the canvas => Setup a translation
+            that.touchTranslation_ = that.GetTouchTranslation(event);
+            that.ViewportMouseDown(that.pimpl_, 
+                                  1 /* middle button */,
+                                  that.touchTranslation_[0],
+                                  that.touchTranslation_[1], 0);
+          } else if (event.targetTouches.length == 2) {
+            // Exactly 2 fingers inside the canvas => Setup a pinch/zoom
+            that.touchZoom_ = that.GetTouchZoom(event);
+            var z0 = that.touchZoom_;
+            that.ViewportMouseDown(that.pimpl_, 
+                                  2 /* right button */,
+                                  z0[0],
+                                  z0[1], 0);
+          }        
+        }
+      });
+    }  
+
+  public ResetTouch() {
+    if (this.touchTranslation_ ||
+        this.touchZoom_) {
+      this.ViewportMouseUp(this.pimpl_);
+    }
+
+    this.touchTranslation_ = false;
+    this.touchZoom_ = false;
+  }
+  
+  public GetTouchTranslation(event) {
+    var touch = event.targetTouches[0];
+    return [
+      touch.pageX,
+      touch.pageY
+    ];
+  }
+    
+  public GetTouchZoom(event) {
+    var touch1 = event.targetTouches[0];
+    var touch2 = event.targetTouches[1];
+    var dx = (touch1.pageX - touch2.pageX);
+    var dy = (touch1.pageY - touch2.pageY);
+    var d = Math.sqrt(dx * dx + dy * dy);
+    return [
+      (touch1.pageX + touch2.pageX) / 2.0,
+      (touch1.pageY + touch2.pageY) / 2.0,
+      d
+    ];
+  }
+    
+}
+}
+  
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