Initial commit

1 files changed, 74 insertions, 0 deletions

diff --git a/validations.asm b/validations.asm
new file mode 100644
index 0000000..12c8e26
--- /dev/null
+++ b/validations.asm
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+global check_angle
+global check_tangent
+global check_cotanget
+
+section .text
+;
+; angle validation
+; [ebp+8] is end angle
+; [ebp+12] is begin angle
+; returns eax=-1 if begin angle is greater than end angle
+; eax=0 if end angle < 0 or > 360
+; eax=1 if angles are correct
+;
+check_angle:	push ebp
+		mov ebp, esp
+		mov eax, [ebp+8]	; end_angle
+		mov edx, [ebp+12]	; begin_angle
+		cmp edx, eax
+		jg .error2
+		cmp eax, 0
+		jl .error1
+		cmp eax, 360
+		jg .error1
+		mov eax, 1
+		jmp .quit
+.error1:	xor eax, eax
+		jmp .quit
+.error2:	mov eax, -1
+.quit:		pop ebp
+		ret
+
+;
+; tangent test
+; [ebp+8] is integer angle
+; [ebp+12] is pointer to tangent buffer
+; buffer=ffffffffh if tangent=90 or 270
+; else buffer=1
+;
+check_tangent:	push ebp
+		mov ebp, esp
+		mov eax, [ebp+8]		; value
+		mov ecx, [ebp+12]		; address
+		mov dword [ecx], 1		; true
+		cmp eax, 90
+		je .undefined
+		cmp eax, 270
+		je .undefined
+		jmp .quit
+.undefined:	mov dword [ecx], 0ffffffffh	; false (255)
+.quit:		pop ebp
+		ret
+
+;
+; cotangent test
+; [ebp+8] is integer angle
+; [ebp+12] is pointer to cotangent buffer
+; buffer=ffffffffh if cotangent=0, 180 or 360
+; else buffer=1
+;
+check_cotanget:	push ebp
+		mov ebp, esp
+		mov eax, [ebp+8]	; value
+		mov ecx, [ebp+12]	; address
+		mov dword [ecx], 1	; true
+		cmp eax, 0
+		je .undefined
+		cmp eax, 180
+		je .undefined
+		cmp eax, 360
+		je .undefined
+		jmp .quit
+.undefined:	mov dword [ecx], 0ffffffffh	; false (255)
+.quit:		pop ebp
+		ret