OpenEuphoria

2. Re: SFML Wrapper Error?

• Posted by ghaberek (admin) Jun 10, 2019
• 1666 views

I think you need to check the value of eventType before attempting to peek deeper into the structure. sfEvent is actually a union, so its contents will be different for the various event types.

-Greg

4. Re: SFML Wrapper Error?

• Posted by ghaberek (admin) Jun 10, 2019
• 1607 views

I just had some time to sit down and test your code. I get the same error on 4.0 or 4.1 32-bit.

You're storing the values as integer, but sometimes you might not get back a value that fits into an integer type, which is only 31-bits on 32-bit platforms. I ran your code many times and once or twice I got an error that type check error. It seems this only occurs when the library loads into an area of memory that already exceeds the size of an integer.

One thing to keep in mind about Windows, is that it basically has a mind of its own when it comes to unloading DLLs from memory. It will hang onto them for some indeterminate period of time and then release them. So, if your application runs the first time and it works, it will keep working until some time goes by without the application having loaded the DLL. Then, you have a random chance of Windows loading the DLL into a larger-than-integer area of memory.

Regardless of the cause, the solution is simple: when accessing memory directly with peek/poke routines, always store your values as atom types.

-Greg

6. Re: SFML Wrapper Error?

• Posted by petelomax Jun 12, 2019
• 1570 views

	  integer alt = peek4s(event+8) 
	  integer control = peek4s(event+13) 
	  integer shift = peek4s(event+16) 

I have to say that I would be quite surprised if that should not be

	  integer alt = peek4s(event+8) 
	  integer control = peek4s(event+12) 
	  integer shift = peek4s(event+16) 

8. Re: SFML Wrapper Error?

• Posted by ghaberek (admin) Jun 13, 2019
• 1555 views

 
  integer alt = peek4s(event+8) 
  integer control = peek4s(event+13) 
  integer shift = peek4s(event+16) 

 
  integer alt = peek4s(event+8) 
  integer control = peek4s(event+12) 
  integer shift = peek4s(event+16) 

No, Pete's right. sfBool is typedef'd as an int so the offsets should all be four-byte aligned.

https://github.com/SFML/CSFML/blob/master/include/SFML/Config.h#L150

This is why I always recommend planning out structs with constant instead of using magic numbers.

https://github.com/SFML/CSFML/blob/master/include/SFML/Window/Event.h#L72

//////////////////////////////////////////////////////////// 
/// \brief Keyboard event parameters 
///  
//////////////////////////////////////////////////////////// 
typedef struct 
{ 
    sfEventType type; 
    sfKeyCode   code; 
    sfBool      alt; 
    sfBool      control; 
    sfBool      shift; 
    sfBool      system; 
} sfKeyEvent; 

constant 
    sfKeyEvent__type    =  0, -- sfEventType (int) 
    sfKeyEvent__code    =  4, -- sfKeyCode   (int) 
    sfKeyEvent__alt     =  8, -- sfBool      (int) 
    sfKeyEvent__control = 12, -- sfBool      (int) 
    sfKeyEvent__shift   = 16, -- sfBool      (int) 
    sfKeyEvent__system  = 20, -- sfBool      (int) 
    SIZEOF_SFKEYEVENT   = 24, 
$ 
 
atom alt     = peek4s( event + sfKeyEvent__alt ) 
atom control = peek4s( event + sfKeyEvent__control ) 
atom shift   = peek4s( event + sfKeyEvent__shift ) 

-Greg