Merge branch 'yczhang' into gallery

README-ZH.md

 
 #### Wiki
 
-目前开发团队仍在改进UIWidgets Wiki。 由于UIWidgets主要来源于Flutter，你也可以参考Flutter Wiki中与UIWidgets API对应部分的详细描述。同时，你可以加入我们的讨论组(https://connect.unity.com/g/uiwidgets)。
+目前开发团队仍在改进UIWidgets Wiki。 由于UIWidgets主要来源于Flutter，你也可以参考Flutter Wiki中与UIWidgets API对应部分的详细描述。同时，你可以加入我们的讨论组( https://connect.unity.com/g/uiwidgets )。
  
 #### 常问问题解答
 

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/painting/image_cache.cs

                     D.assert(this._pendingImages.ContainsKey(key));
                     this._pendingImages.Remove(key);
 
-                    int imageSize = info?.image == null ? 0 : info.image.width & (info.image.height * 4);
+                    int imageSize = info?.image == null ? 0 : info.image.width * info.image.height * 4;
                     _CachedImage cachedImage = new _CachedImage {
                         completer = result,
                         sizeBytes = imageSize,

Runtime/ui/painting/path.cs

             float dlx = dy;
             float dly = -dx;
 
-
-            dst.Add(new Vector2(px + dlx * w, py + dly * w));
-            dst.Add(new Vector2(px - dlx * w, py - dly * w));
-                float a = i / (ncap - 1) * Mathf.PI;
+                float a = (float) i / (ncap - 1) * Mathf.PI;
+                dst.Add(new Vector2(px - dlx * ax - dx * ay, py - dly * ax - dy * ay));
-                dst.Add(new Vector2(px - dlx * ax + dx * ay, py - dly * ax + dy * ay));
+
+            dst.Add(new Vector2(px + dlx * w, py + dly * w));
+            dst.Add(new Vector2(px - dlx * w, py - dly * w));
         }
 
         public static void roundCapEnd(this List<Vector3> dst, PathPoint p,
             float dlx = dy;
             float dly = -dx;
 
+            dst.Add(new Vector2(px + dlx * w, py + dly * w));
+            dst.Add(new Vector2(px - dlx * w, py - dly * w));
+
-                float a = i / (ncap - 1) * Mathf.PI;
+                float a = (float) i / (ncap - 1) * Mathf.PI;
-                dst.Add(new Vector2(px - dlx * ax - dx * ay, py - dly * ax - dy * ay));
+                dst.Add(new Vector2(px - dlx * ax + dx * ay, py - dly * ax + dy * ay));
-
-            dst.Add(new Vector2(px + dlx * w, py + dly * w));
-            dst.Add(new Vector2(px - dlx * w, py - dly * w));
         }
 
         public static void chooseBevel(bool bevel, PathPoint p0, PathPoint p1, float w,
 
                 var n = Mathf.CeilToInt((a0 - a1) / Mathf.PI * ncap).clamp(2, ncap);
                 for (var i = 0; i < n; i++) {
-                    float u = i / (n - 1);
+                    float u = (float) i / (n - 1);
                     float a = a0 + u * (a1 - a0);
                     float rx = p1.x + Mathf.Cos(a) * rw;
                     float ry = p1.y + Mathf.Sin(a) * rw;
 
                 var n = Mathf.CeilToInt((a1 - a0) / Mathf.PI * ncap).clamp(2, ncap);
                 for (var i = 0; i < n; i++) {
-                    float u = i / (n - 1);
+                    float u = (float) i / (n - 1);
                     float a = a0 + u * (a1 - a0);
                     float lx = p1.x + Mathf.Cos(a) * lw;
                     float ly = p1.y + Mathf.Sin(a) * lw;

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;
         }