Initial Commit

common/MATH.INC

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+; **************************************************************************
+; FILE:MATH.INC
+; FUNCTION: MATH MACROS INCLUDE FILE
+; AUTHOR: SEAN M. KESSLER
+;****************************************************************************
+round MACRO
+	mov  edx,eax                    ; move value into edx register
+	and  edx,0000FFFFh              ; get remainder into edx register
+	shr  eax,10h                    ; get whole number to eax register
+	cmp  edx,7FFFh                  ; if remainder > 32767, increment eax
+	db   7Eh                        ; the next two bytes comprise "jle +2" (ie)
+	db   01h                        ; jump passed the increment esx insruction
+	inc  eax                        ; increment value in eax
+ENDM
+
+absolute MACRO varOne
+LOCAL @@return
+	cmp  varOne,00h                 ; check varOne with zero 
+	jge  @@return                   ; if it's greater than or equal then return
+  neg  varOne                     ; otherwise make it positive
+@@return:
+ENDM
+
+multiply MACRO varOne,varTwo
+	mov    eax,varOne               ; move varOne into eax register
+	mov    edx,varTwo               ; move varTwo into edx register
+	imul   eax,edx                  ; perform multiply, result to eax
+ENDM
+
+mulshort MACRO varOne,varTwo      ; multiply r/m16->eax
+	mov  ax,varOne                  ; move varOne into ax register
+	mov  dx,varTwo                  ; move varTwo into dx register
+	and  eax,0FFFFh                 ; clear out high word of eax register
+	and  edx,0FFFFh                 ; clear out high word of edx register
+	imul eax,edx                    ; perform multiply, result to eax
+ENDM
+
+divide MACRO varOne,varTwo        ; divide MACRO varOne,varTwo
+	mov    eax,varOne               ; move varOne into eax register
+	mov    ebx,varTwo               ; move varTwo into ebx register
+	cdq                             ; convert doubleword in eax to quadword at edx:eax
+	idiv   ebx                      ; divide eax/ebx result to eax, remainder to edx
+ENDM
+
+divshort MACRO varOne,varTwo      ; divide r/m16->eax
+	mov    ax,varOne                ; move varOne into ax register
+	mov    bx,varTwo                ; move varTwo into bx register
+	and    eax,0FFFFh               ; clear out high word of eax register
+	and    ebx,0FFFFh               ; clear out high word of ebx register
+	cdq                             ; convert doubleword in eax to quadword at edx:eax
+	idiv   ebx                      ; divide eax/ebx result to eax, remainder to edx
+ENDM
+