在HTML5 Canvas中使用GWT是个好主意吗？

Question

I am new to GWT. I started using it three days ago with HTML5 Canvas for drawing some basic shapes with basic animation (nothing fancy, just straight lines moving up and down). Before moving to GWT, I wrote some javascript code to do the same thing.

And I noticed that javascript is a lot faster in rendering the shapes than GWT. Considering that GWT is also javascript, is there something that I do not know that is slowing GWT down? I also want to know if it is a good idea to use GWT for canvas at all, or is it a better idea to stick to javascript for drawing on cavas?

Answer 1

How do you run your GWT application? In development mode? In development mode the code runs much slower than in production. If you compile your application and deploy it to an application server it should be as fast as native javascript (because then it is actually native javascript! :))

Answer 2

Honestly, I would suggest taking a strong look at dart. It compiles down to faster javascript than GWT and is looking to have greater support by google in general.

GWT produces javascript that is generally around 1.5->2.0 slower than native javascript. For a business app, that usually isn't a big deal. GWT makes a lot of sense when you are looking for backwards compatibility and strong support for java and java like features.

Where you are using HTML5, the compatibility benefit of GWT becomes moot. At that point, you are targeting the browsers which dart supports.

(The "why" gwt is slower has to do with java. GWT has to do a lot of work to ensure that java constraints and behavior is maintained. Dart was designed with an eye towards javascript compilation)

Answer 3

the Only advantage i can seen in using GWTCanvas is browser compatibility. Its mainly focused on the browser support. It doesn't have all the features implemented in HTML5 Canvas element. If you are looking for all the canvas features then better to move along with javascript.