CTRLPainter now handles scaling from the UI interface. Also added ability (and UI button) to fit-to-canvas

app/js/ctrls/CTRLPainter.js

 input.enableMouseInput(true);
 input.preventDefaults = true;
 
-// Mouse handling...
-/*input.listen("mousemove", handle_mouseevent);
-input.listen("mousedown", handle_mouseevent);
-input.listen("mouseup", handle_mouseevent);
-input.listen("mouseclick", handle_mouseclickevent);
-*/
-
 
 /* --------------------------------------------------------------------
  * CTRLPainter
         } else if (this.__palette !== null && this.__surface.palette !== this.__palette){
           this.__surface.palette = this.__palette;
         }
+        this.scale_to_fit();
         this.center_surface();
       }
       RenderD();
     }).bind(this);
     input.listen("wheel", handle_scale);
 
+
+    var elscale = document.querySelector("#painter_scale");
+    if (elscale){
+      var self = this;
+      elscale.addEventListener("change", function(e){
+        var val = Number(this.value);
+        self.scale = val; 
+        RenderD();
+      });
+      elscale.value = this.__scale;
+    }
+
+    var handle_fittocanvas = (function(){
+      this.scale_to_fit();
+      this.center_surface();
+      RenderD();
+    }).bind(this);
+    GlobalEvents.listen("painter-fit-to-canvas", handle_fittocanvas);
+
     var handle_togglegrid = (function(target, args){
       if (args.show){
         target.classList.add("pure-button-active");
     if (typeof(s) !== 'number')
       throw new TypeError("Expected number value.");
     this.__scale = Math.max(0.1, Math.min(100.0, s));
+    var elscale = document.querySelector("#painter_scale");
+    if (elscale){
+      elscale.value = this.__scale;
+    }
   }
 
   get showGrid(){return this.__gridEnabled;}
       context = canvas.getContext("2d");
       if (!context)
         throw new Error("Failed to obtain canvas context.");
-      context.imageSmoothingEnabled = false;
+      context.imageSmoothingEnabled = false; 
       ResizeCanvasImg(canvas.clientWidth, canvas.clientHeight); // A forced "resize".
       input.mouseTargetElement = canvas;
 
+      this.scale_to_fit();
       this.center_surface();
     }
     return this;
     if (canvas === null || this.__surface === null)
       return;
 
-    this.__offset[0] = Math.floor((canvas.clientWidth - this.__surface.width) * 0.5);
-    this.__offset[1] = Math.floor((canvas.clientHeight - this.__surface.height) * 0.5);
+    this.__offset[0] = Math.floor((canvas.clientWidth - (this.__surface.width * this.__scale)) * 0.5);
+    this.__offset[1] = Math.floor((canvas.clientHeight - (this.__surface.height * this.__scale)) * 0.5);
     return this;
   }
 
+  scale_to_fit(){
+    if (canvas === null || this.__surface === null)
+      return;
+
+    var sw = canvas.clientWidth / this.__surface.width;
+    var sh = canvas.clientHeight / this.__surface.height;
+    var s = Math.min(sw, sh).toString();
+    var di = s.indexOf(".");
+    if (di >= 0)
+      s = s.slice(0, di+2);
+    this.scale = Number(s);
+  }
+
   render(){
     if (context === null || this.__surface === null)
       return;

views/ctrlpainter.html

                 Scale : 
               </label>
               <input id="painter_scale" class="input-u-1-6" type="number" min="0.5" max="1000" step="0.1" value ="1"/>
+
+              <button emit="painter-fit-to-canvas" class="pure-button">
+                <i class="fa fa-expand-arrows-alt"></i>
+              </button>
             </div>
 
             <div class="pure-u-1-3 simple-padding">