Merge pull request #110 from UnityTech/xwzhu

performance step 1

Runtime/material/text_theme.cs

             return !Equals(left, right);
         }
 
+        int? _cachedHashCode = null;
+            if (this._cachedHashCode != null) {
+                return this._cachedHashCode.Value;
+            }
             unchecked {
                 var hashCode = this.display4.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.display3.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.button.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.subtitle.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.overline.GetHashCode();
+
+                this._cachedHashCode = hashCode;
                 return hashCode;
             }
         }

Runtime/material/theme_data.cs

             return !Equals(left, right);
         }
 
+        int? _cachedHashCode = null;
+
+            if (this._cachedHashCode != null) {
+                return this._cachedHashCode.Value;
+            }
             unchecked {
                 var hashCode = this.brightness.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.primaryColor.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.colorScheme.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.dialogTheme.GetHashCode();
                 hashCode = (hashCode * 397) ^ this.typography.GetHashCode();
+
+                this._cachedHashCode = hashCode;
                 return hashCode;
             }
         }
                 return true;
             }
 
-            return this.baseTheme == other.baseTheme &&
-                   this.localTextGeometry == other.localTextGeometry;
+            return ReferenceEquals(this.baseTheme, other.baseTheme) &&
+                   ReferenceEquals(this.localTextGeometry, other.localTextGeometry);
         }
 
         public override bool Equals(object obj) {
         public V putIfAbsent(K key, Func<V> value) {
             D.assert(key != null);
             D.assert(value != null);
-
-            if (this._cache.ContainsKey(key)) {
-                return this._cache[key];
+            
+            V get_value;
+            if (this._cache.TryGetValue(key, out get_value)) {
+                return get_value;
             }
 
             if (this._cache.Count == this._maximumSize) {

Runtime/ui/painting/shadow_utils.cs

 using UnityEngine;
 
 namespace Unity.UIWidgets.ui {
-    public static class ShadowUtils {
-        public const bool _drawShadowFlag = false;
-        
+    static class ShadowUtils {
+        public static bool kUseFastShadow = true;
+
         public const float kAmbientHeightFactor = 1.0f / 128.0f;
         public const float kAmbientGeomFactor = 64.0f;
 
 
         public static void drawShadow(Canvas canvas, Path path, Vector3 zPlaneParams, Vector3 devLightPos,
             float lightRadius, Color ambientColor, Color spotColor, int flags) {
-            if (!_drawShadowFlag) {
-                return;
+            if (kUseFastShadow) {
+                drawShadowFast(canvas, path, zPlaneParams, devLightPos, lightRadius, ambientColor, spotColor, flags);
-            
+            else {
+                drawShadowFull(canvas, path, zPlaneParams, devLightPos, lightRadius, ambientColor, spotColor, flags);
+            }
+        }
+
+        static void drawShadowFull(Canvas canvas, Path path, Vector3 zPlaneParams, Vector3 devLightPos,
+            float lightRadius, Color ambientColor, Color spotColor, int flags) {
             Matrix3 viewMatrix = canvas.getTotalMatrix();
 
             //ambient light
             Paint paint2 = new Paint {color = spotColor};
             float sigma2 = convertRadiusToSigma(radius);
             paint2.maskFilter = MaskFilter.blur(BlurStyle.normal, sigma2);
+            canvas.drawPath(path, paint2);
+
+            canvas.restore();
+        }
+
+        static void drawShadowFast(Canvas canvas, Path path, Vector3 zPlaneParams, Vector3 devLightPos,
+            float lightRadius, Color ambientColor, Color spotColor, int flags) {
+            Matrix3 viewMatrix = canvas.getTotalMatrix();
+
+            //ambient light
+            float devSpaceOutset = ambientBlurRadius(zPlaneParams.z);
+            float oneOverA = ambientRecipAlpha(zPlaneParams.z);
+            float blurRadius = 0.5f * devSpaceOutset * oneOverA;
+            float strokeWidth = 0.5f * (devSpaceOutset - blurRadius);
+
+            Paint paint = new Paint {color = ambientColor, strokeWidth = strokeWidth, style = PaintingStyle.fill};
+            canvas.drawPath(path, paint);
+
+            //spot light
+            Matrix3 shadowMatrix = Matrix3.I();
+            float radius = 0.0f;
+
+            if (!getSpotShadowTransform(devLightPos, lightRadius, viewMatrix, zPlaneParams, path.getBounds(),
+                shadowMatrix, ref radius)) {
+                return;
+            }
+
+            canvas.save();
+            canvas.setMatrix(shadowMatrix);
+            Paint paint2 = new Paint {color = spotColor};
             canvas.drawPath(path, paint2);
 
             canvas.restore();

Runtime/widgets/automatic_keep_alive.cs

 
         public Ticker createTicker(TickerCallback onTick) {
             this._tickers = this._tickers ?? new HashSet<Ticker>();
-            var result = new _AutomaticWidgetTicker<T>(onTick, this, debugLabel: "created by " + this);
+
+            var debugLabel = "";
+            D.assert(() => {
+                debugLabel = "created by " + this;
+                return true;
+            });
+            var result = new _AutomaticWidgetTicker<T>(onTick, this, debugLabel: debugLabel);
             this._tickers.Add(result);
             return result;
         }

Runtime/widgets/ticker_provider.cs

                     "mixing in a SingleTickerProviderStateMixin, use a regular TickerProviderStateMixin."
                 );
             });
-            this._ticker = new Ticker(onTick, debugLabel: "created by " + this);
+            
+            var debugLabel = "";
+            D.assert(() => {
+                debugLabel = "created by " + this;
+                return true;
+            });
+            this._ticker = new Ticker(onTick, debugLabel: debugLabel);
             return this._ticker;
         }
 
 
         public Ticker createTicker(TickerCallback onTick) {
             this._tickers = this._tickers ?? new HashSet<Ticker>();
-            var result = new _WidgetTicker<T>(onTick, this, debugLabel: "created by " + this);
+
+            var debugLabel = "";
+            D.assert(() => {
+                debugLabel = "created by " + this;
+                return true;
+            });
+            var result = new _WidgetTicker<T>(onTick, this, debugLabel: debugLabel);
             this._tickers.Add(result);
             return result;
         }