update

Assets/UIWidgets/Tests/CanvasAndLayers.cs

 
         void drawImageRect()
         {
-            if (_stream == null)
+            if (_stream == null || _stream.completer == null || _stream.completer._currentImgae == null)
             {
                 return;
             }
                 Rect.fromLTWH(150, 50, 250, 250),
                 Rect.fromLTWH(150, 50, 250, 250),
                 paint,
-                _stream
+                _stream.completer._currentImgae.image
             );
         }
 
                 paint);
 
             var picture = pictureRecorder.endRecording();
-            Debug.Log("picture.paintBounds: " + picture.paintBounds);
 
             var editorCanvas = new CanvasImpl();
             editorCanvas.concat(Matrix4x4.Rotate(Quaternion.Euler(0, 0, -5)));

Assets/UIWidgets/ui/painting/canvas.cs

 
         void drawPicture(Picture picture);
 
-        void drawImageRect(Rect src, Rect dst, Paint paint, ImageStream stream);
+        void drawImageRect(Rect src, Rect dst, Paint paint, Image image);
 
         void concat(Matrix4x4 transform);
 
             });
         }
 
-        public void drawImageRect(Rect src, Rect dst, Paint paint, ImageStream stream)
+        public void drawImageRect(Rect src, Rect dst, Paint paint, Image image)
-                stream = stream,
+                image = image,
                 src = src,
                 dst = dst,
             });

Assets/UIWidgets/ui/painting/canvas_impl.cs

             this.restore();
         }
 
-        public void drawImageRect(Rect src, Rect dst, Paint paint, ImageStream stream)
+        public void drawImageRect(Rect src, Rect dst, Paint paint, Image image)
-            if (stream.completer._currentImgae != null)
+            if (image != null)
-                _texture.LoadImage(stream.completer._currentImgae.image.rawData);
+                _texture.LoadImage(image.rawData);
                 Graphics.DrawTexture(dst.toRect(), _texture);
             }
         }

Assets/UIWidgets/ui/painting/draw_cmd.cs

 
     public class DrawImageRect : DrawCmd
     {
-        public ImageStream stream;
+        public Image image;
         public Rect src;
         public Rect dst;
     }