forums.silverfrost.com

[acw]

I'm having problems with a multi-line edit box when compiling with FTN 8.1 that did not occur with previous versions. When using a %eb edit box with user_colours and a callback, if I attempt to scroll the box using the vertical scrollbar thumb text within the box is selected, and the text display flickers, sometimes corrupts and also the application can cash. A similar thing happens if I attempt to select a block of text using mouse click and drag. This was all working fine up to FTN 8 (compiling as x86 code in Windows 10)

Here's some demo code:

[PaulLaidler]

I have made a note that this needs investigating.

[PaulLaidler]

I have tested this code and it works OK for me for Win32. I am using v8.2 of FTN95 and the corresponding ClearWin+ library. However, I don't know of any relevant changes in ClearWin+ since this thread was started.

The Fortran code presented above has not be adapted for 64 bit compilation.
As it is, it doesn't run well under 64 bits but that is not surprising since there are important changes that must be made to the code for a 64 bit executable.

[acw]

Unfortunately this is still a problem with 8.2. On further investigation it appears to occur only on certain mouse hardware (in my case a Logitech G602), with or without specific mouse drivers. It's repeated on different OSes (Win 8.1 and 10 at least) and PCs and even happens when the test program is run on a different PC via Remote Desktop. The behaviour is the same in all cases, scrolling up and down using a mouse on the vertical thumb causes random left/right scrolling, selection of text, flickering and eventually a crash. The crash doesn't always occur in the same place within salflibc.dll although it looks like it is generally related to the WM_MOUSEMOVE event handler. Using a different mouse doesn't cause the same problem (even with the G602 plugged in at the same time).

The G602 is a gaming mouse so maybe it's in some way related to a higher frequency of mouse events? MS Spy++ shows an awfully large number of WM_MOUSEMOVES and WM_TIMER events being fired. I've not come across anything similar in Windows or any other apps using this mouse.

This isn't a problem when compiled under compiler versions prior to 8.00 so it looks like some interaction between the data from the mouse and a change in ClearWin+ between 7.2 and 8.0.

If there is any more info or testing I can do (or a version of salflib with debug symbols maybe?) let me know.

Thanks,
Alan

[PaulLaidler]

Alan

At the moment I am not able to reproduce the problem.

Can you confirm

a) you are using the Win32 platform and not x64 (64 bits)
b) the problem only occurs when using [user_colours]
c) the problem only occurs when %eb has a callback.

[acw]

Paul,
a) Yes, Win32 compilier, running on Windows 10, 8.1 and 7 x64
b) Yes, delete user_colours and its fine
c) Yes, actually it is only the combination of user_colours and a call to CLEARWIN_STRING@('CALLBACK_REASON') within the CB. Just commenting out the function call in the fixes it.

I have just found another system with the problem with lots of different mice. This is an old iMac with Windows 7 x64 BootCamp and various different wired MS mice. It crashes almost immediately with a ClearWin Access Violation stack trace:

[wahorger]

Try a different return value for EbCtrlCB.

You are currently using 0 as the return value.

I had to change my callback return value from a 1 to a 2 to get a list view control to work without flickering while I navigated around the box, selected rows, etc.

[PaulLaidler]

Using the above traceback, I have made a guess at the likely cause of failure and applied a fix. This should prevent the crash but may not remove the flicker etc..

The fix will be in the next release of the DLLs.

[JohnCampbell]

[acw]

Unfortunately the callback return values don't fix the problem - %eb has specific CB return requirements and it's more than just redraw flicker really as I get random apparent mouse clicks, text selection and other fun stuff!

Paul, that sounds promising, when do you think you'll release the updated DLLs? If you want me to have a quick go then I'm happy to test something out if it will help.

John - to add some more callback excitement, in the case of %eb the value of 0 should be returned if the callback doesn't handle the response to control keys (Delete, Backspace etc.) so not the same as the general behaviour which would be to close the window.

[PaulLaidler]

Alan

Normally I would release intermim DLLs quite quickly but we probably need to wait till most of our users are up to date with version 8.2 of FTN95.