Merge branch 'master' of github.com:UnityTech/UIWidgets into allocator2 (CONT.)

# Conflicts:
#	Runtime/ui/painting/canvas_impl.cs

Author: zhuxingwei

Runtime/ui/renderer/allocator/uipath_cache_manager.cs

@@ -2,10 +2,10 @@
 
 namespace Unity.UIWidgets.ui {
     public static class uiPathCacheManager {
-        static Dictionary<uint, uiPath> cache = new Dictionary<uint, uiPath>(256);
+        static readonly Dictionary<uint, uiPath> cache = new Dictionary<uint, uiPath>(256);
 
         //remove unused cache items every 1 frame
-        static Dictionary<uint, bool> touched = new Dictionary<uint, bool>(256);
+        static readonly Dictionary<uint, bool> touched = new Dictionary<uint, bool>(256);
 
         static float curFrame;
 

Runtime/ui/renderer/cmdbufferCanvas/rendering/render_layer.cs

@@ -8,7 +8,7 @@ internal class RenderLayer : PoolObject {
             public int rtID;
             public int width;
             public int height;
-            public FilterMode filterMode = FilterMode.Point;
+            public FilterMode filterMode = FilterMode.Bilinear;
             public bool noMSAA = false;
             public uiRect layerBounds;
             public uiPaint? layerPaint;
@@ -38,7 +38,7 @@ public Vector4 viewport {
             }
 
             public static RenderLayer create(int rtID = 0, int width = 0, int height = 0,
-                FilterMode filterMode = FilterMode.Point,
+                FilterMode filterMode = FilterMode.Bilinear,
                 bool noMSAA = false, uiRect? layerBounds = null, uiPaint? layerPaint = null, bool ignoreClip = true) {
                 D.assert(layerBounds != null);
                 var newLayer = ObjectPool<RenderLayer>.alloc();

Runtime/ui/renderer/common/paint.cs

@@ -37,7 +37,7 @@ public static uiImageFilter blur(float sigmaX = 0.0f, float sigmaY = 0.0f) {
             return new _uiBlurImageFilter(sigmaX, sigmaY);
         }
 
-        public static uiImageFilter matrix(uiMatrix3 transform, FilterMode filterMode = FilterMode.Point) {
+        public static uiImageFilter matrix(uiMatrix3 transform, FilterMode filterMode = FilterMode.Bilinear) {
             return new _uiMatrixImageFilter(transform, filterMode);
         }
     }
@@ -87,7 +87,7 @@ public uiPaint(
             StrokeCap strokeCap = StrokeCap.butt,
             StrokeJoin strokeJoin = StrokeJoin.miter,
             float strokeMiterLimit = 4.0f,
-            FilterMode filterMode = FilterMode.Point,
+            FilterMode filterMode = FilterMode.Bilinear,
             uiColorFilter? colorFilter = null,
             uiMaskFilter? maskFilter = null,
             uiImageFilter backdrop = null,