ios - CALayer zPosition ordering with extremely large values -


I have attended an issue where the core animation appears to be zPosition for my values Ignoring the values ​​become larger.

example

It can be easily replicated 

  CGFloat largeZPosition = 1000000000; CALayer * topLayer = ... CALayer * bottomLayer = ... belowLeather.frame = CGFFetset (toplinerframe, 50, 50); TopLayer.zPosition = Big ZPosition + 1; Downlayer ZPosition = Large ZPosition; // Sort arithmetic array in wrong order RootLayer.sublayers = @ [header, bottom letter];

With small values ​​for z-position, this function, as expected, even if the sub-column array is not sorted correctly, the bottom side is displayed on the top side Such as:

correct

However, the examples shown above , The result is as follows:

Enter image details here

Obviously this is not right.

Question

I'm unable to classify manual inventory for my needs, so I'm relying on zPosition to perform as expected So my question is: How do I work around this problem? Thank you.

That's because Quartzcore has been composed of zPosition to float , therefore it loses the accuracy when CGFloat is double . IEEE single-precision floating-point numbers use 24 bits meaning more accurate, so more than 2 ^ 24 integral numbers can not be properly represented. For example, 

  float biggeonation = 1000000000; Float bigZPositionPlus1 = 1000000001; NSLog (@ "% F% F% D", Largegeonation, LargeGroup Plus 1, Biggerency == LargeJustnessPlus1);

Output 

  1000000000.000000 1000000000.000000 1

The next accurate representational integer is 1000000064.

Note that CALayer.zPosition is defined as CGFloat and it is capable of having an integral value greater than 2 ^ 24 , As long as the underlying CGFloat is able to do this 

  layer.zPosition = 1000000001; NSLog (@ "% F", Layer .ZPosition); 64-bit OS X

Where CGFloat is double , output 

  1000000001.000000

Therefore, on CALayer public purpose - at C class level, it has not been lost. Wherever there is a conversion for single-precision float anywhere in Quartzcor.

I suggest using integral numbers (including the result of extra) which is less than 2 ^ 24. Given that there is a floating-point type in zPosition , you can use small partial values ​​instead of large integral values.


-

Comments

Post a Comment

Popular posts from this blog

sqlite3 - UPDATE a table from the SELECT of another one -

I have the first table article where some data is missing. In the table, articles_tmp I have a part of the missing data. So I want to update the articles. Where the path path is data in articles_tmp.path where the path is not zero . With SQLite , it does not work: update article SET path = (SELECT at.path FROM Articles_tmp as AS, WHERE at.article_id = a.id and a.asp, the text is in the form and not on. It has been transmitted) where the path is null MS Access Along with, it works fine: Update Articles Join the Inner Articles at articles_tmp articles.id = articles_tmp.id SETP articles.path = articles_tmp.path Can anyone help? Sin CE SQL Server Syntax, which I provided, was not working, here this solution With whom I have come. A little modification of your original query, but with my "correlation" suggestion added. There is a SQL Bella for this: Here is the code: update article SET path = (SELECT path from articles_tmp AS T WHERE t.id
Read more

c# - Showing a SelectedItem's Property -

So I have enabled a rightclick option for my DataGrid. I want to display the only chosen property but it is not behaving like what I would like it to display my name and additional. Public category Paymentinfo {public int PaymentNo {get; Set; } Public string date {get; Set; } Public Double Pay {get; Set; } Public Double Principle {get; Set; } Public Double Interest {get; Set; } Public Double Balance {Received; Set; }} Private Zero MenuItem_OnClick (Object Sender, RoutedEventArgs e) {MessageBox.Show (AmortGrid.SelectedItem.ToString ()); } I'm trying to apply it without using a View Module! If I place a breakpoint where the messagebox and the recipient place it on selected ITEM, then this property will display the payment. A date-payment-principle-interest-balance is the only value that needs payment. Was hoping that it would be something like this MessageBox.Show (AmortGrid.SelectedItem.PaymentNo.ToString ()); When you call ToString () So you get the class typ
Read more

javascript - Render HTML after each iteration in loop -

I'm trying to gradually increase the font size of text on a web page. The code works in my place, although the new HTML / CSS does not render after every iteration of the loop and when all this is done, then display only the text of 100 px size. To see the text as if it is slowly zooming, I need to do this JavaScript is down because it is being used from a different file here is what I have ... < Pre> & lt; P class = "game-title" style = "font-size: 50px" & gt; Test & lt; / P & gt; Function sleep (milliseconds) {var start = new date (). GetTime (); For (var i = 0; i & lt; 1e7; i ++) {if ((new date). GetTime () - start) & gt; Milliseconds {break; CSS ('font-size', 'parseInt ($ (' game-title '). CSS (' font-size ')) + 1 + "pixels"); } While (parasont ($ ('# text'). Css ('font-size')) & lt; = 100) {sleep (1000); IncreaseSize (); Using CSS: Use of jQuery (sample):
Read more