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Klarre · Mar 3rd, 2008, 2:34 PM

Hi!

I am working on a system managing key presses in a MASM application. The problem is that I must be doing something wrong with the array that keeps the press status of each key. (bool g_keys[256] // Position 0x20 means VK_SPACE i e.)

The "input_set_key" function always returns a non-zero value like my memset hasn't done anything with the array.

What can be the problem? I can't see it...
Thanks alot for your helpfulness!

/Klarre

(Toggle Plain Text)

.data

g_keys dd 0	; Pointer to the array of keys

.code

; ------------------------------------------------------------------------------
input_create proc
	invoke crt_malloc, 256	; Allocate 256 Bytes for the key array
	mov g_keys, eax	; Store the key array pointer

	invoke crt_memset, g_keys, 0, 256	; Make sure no buttons are pressed

	invoke input_is_key_pressed, 27	; DEBUG TEST. Returns a non-zero value

	xor eax, eax

	ret
input_create endp

; ------------------------------------------------------------------------------
input_is_key_pressed proc key:dword
	lea eax, [g_keys]	; Get the key array address
	add eax, key	; Offset to the correct position in the array
	mov eax, [eax]		; Read the value on the position in the array

	ret
input_is_key_pressed endp

end

Mar 3rd, 2008, 2:34 PM	#1
Klarre Game engine designer Join Date: May 2005 Location: Sweden Posts: 291 Rep Power: 4	[MASM32] Working with arrays Hi! I am working on a system managing key presses in a MASM application. The problem is that I must be doing something wrong with the array that keeps the press status of each key. (bool g_keys[256] // Position 0x20 means VK_SPACE i e.) The "input_set_key" function always returns a non-zero value like my memset hasn't done anything with the array. What can be the problem? I can't see it... Thanks alot for your helpfulness! /Klarre (Toggle Plain Text) .data g_keys dd 0 ; Pointer to the array of keys .code ; ------------------------------------------------------------------------------ input_create proc invoke crt_malloc, 256 ; Allocate 256 Bytes for the key array mov g_keys, eax ; Store the key array pointer invoke crt_memset, g_keys, 0, 256 ; Make sure no buttons are pressed invoke input_is_key_pressed, 27 ; DEBUG TEST. Returns a non-zero value xor eax, eax ret input_create endp ; ------------------------------------------------------------------------------ input_is_key_pressed proc key:dword lea eax, [g_keys] ; Get the key array address add eax, key ; Offset to the correct position in the array mov eax, [eax] ; Read the value on the position in the array ret input_is_key_pressed endp end .data g_keys dd 0 ; Pointer to the array of keys .code ; ------------------------------------------------------------------------------ input_create proc invoke crt_malloc, 256 ; Allocate 256 Bytes for the key array mov g_keys, eax ; Store the key array pointer invoke crt_memset, g_keys, 0, 256 ; Make sure no buttons are pressed invoke input_is_key_pressed, 27 ; DEBUG TEST. Returns a non-zero value xor eax, eax ret input_create endp ; ------------------------------------------------------------------------------ input_is_key_pressed proc key:dword lea eax, [g_keys] ; Get the key array address add eax, key ; Offset to the correct position in the array mov eax, [eax] ; Read the value on the position in the array ret input_is_key_pressed endp end __________________ http://www.klarre.se Last edited by Klarre; Mar 3rd, 2008 at 2:58 PM.