Major ipad performance problem using landscape

I made a basic performance test for the new ipad - I was pleasantly surprised by getting 60 fps with about 250 instances in retina mode with safari.

Until I tried it in landscape mode, which slams the framerate so hard I can't get ANY sprites on screen at 60fps.

http://www.amirai.net/ipad/sprites/

Give it a try - load it up on a new ipad and switch between portrait and landscape modes and watch the difference.

It happens in another game I'm making too. Any idea why this happens?

Here's the .capx if you want it: http://www.amirai.net/ipad/sprites/ipadfps.zip

Same here.

My guess is the extra real estate it has to keep track of.

What extra real estate? It's the same number of pixels, so that shouldn't make a difference.

Ok, I guess thats right, but the initial coordinates might add width to height.

Another example - the space blaster performance test does the same: scirra.com/labs/sbperf

In addition, the text object that displays the stats appears to be not redrawing itself correctly in landscape mode either.

I ran into the same problem when I tested my game in Safari on the new iPad as well. Buttery smooth in portrait mode, but since my resolution isn't made for that it has awkward ghosting and a ton of black space. Turn it landscape and the FPS falls so dramatically it is fairly unplayable. I have not been able to test this on any other idevices yet.

Want to make sure this thread wasn't missed. Ashley - any ideas?

Wow, this is really strange. I can't see why this is happening. Maybe the iPad defaults with Portrait and it takes a lot of processing power to transform it into landscape. Although I can't see why that would happen. Maybe this problem will be fixed in iOS 6?

I'm curious to see if this works better on landscape in iOS 6. I'm going to see if I can borrow my boss's new iPad again and give it a test. I tried my game as a web app on a friend's iPod Touch and noticed the same deal though. Great performance in portrait, but poor performance in landscape. Quite strange.

The problem is that it starts out with a set of coordinates, then you ask it to transform those to another set 2048, 1536, then to 1536, 2048.

There's a couple of different ways to do the transform, but think about it, the Ipad wasn't made for that kind of activity.

Anyway ios6 portrait looks to be in the 50-60's, and landscape...

acts strange, goes from 10 fps to 60 fps with little activity.

Its almost as if there was some throttle mechanism.

I don't believe that's the case for a few reasons - 1, the same problem occurs regardless if the page is loaded from the start in landscape mode, 2, I've found other c2 games which do not have this problem, 3, the canvas doesn't seem to have any problem resizing itself on desktop browser windows, 4, there's the matter of the text object not redrawing itself properly in landscape mode, and 5, the iPad was totally made for that kind of activity from the start. It translates everything in every application properly depending which way is up. Why not this?

I too would like to hear from anyone who has ios 6 on their iPad.

Just tested my game on the new iPad with iOS 6. Good performance in Portrait and then performance tanks whenever I rotate it to landscape.

Game resolution is 800x480 utilizing Scale mode with several anchored sprites for the GUI. I'm fairly certain there isn't a performance different between portrait and landscape on any browsers I've tested with on my Android tablet, so this seems to be problem to Safari.

Interesting - I did some more testing, and discovered that if I switched it to full screen letterbox mode, the problem disappears.

Also, interestingly, performance when previewing over LAN on the iPad was half of the exported html5's performance.

Arima : I think you have the "iPhone viewport scalling bug".

You can see the question asked here : http://stackoverflow.com/questions/8380051/what-is-the-iphone-viewport-scale-bug

And the original link, with some explanation to fix things : http://webdesignerwall.com/tutorials/iphone-safari-viewport-scaling-bug

Since, when you rotate, the viewport is cropped, the GPU must have some problem with the composition of the view, explaining the performance problems.

So just adding that code to the HTML page created by C2 would fix the issue? I can't test this because I don't own any Apple devices and never will but in the future I may produce for the iPhone/iPad etc so would like to know how to get around this. Wonder why they've never fixed it if it's so simple?

Can someone test to see if this works?