$include "windowssdk.inc"

window win
Uint fCol,bCol

OPENWINDOW win,0,0,200,400,@CAPTION,0,"Vignette",&main
	CONTROL win,@BUTTON,"Set Top",0,0,200,22,0x50000000,1
	CONTROL win,@BUTTON,"Set Bottom",0,350,200,22,0x50000000,2

fCol=RGB(255,0,0)
	bCol=RGB(0,0,255)
	Vignette(win,0,0,200,400,fCol,bCol)

CheckPrinter()

WaitUntil IsWindowClosed(win)
	end

Sub main(),INT
	SELECT @MESSAGE
CASE @IDCREATE
	CenterWindow win
CASE @IDCLOSEWINDOW
	CLOSEWINDOW win
CASE @IDCONTROL
	SELECT @CONTROLID
case 1
	fCol=ColorRequest(win)
case 2
	bCol=ColorRequest(win)
EndSelect
	Vignette(win,0,0,200,400,fCol,bCol)
ENDSELECT
RETURN 0
EndSub

Sub Vignette(wn as Window,x as int,y as int,w as int,h as int,fc as Uint,bc as UInt)
'linear vignette from top to bottom, fc to bc
   float col[3],sCol[3]
   int i,j
'Split the RGBColour into its components
   col[0]=fc%256 'Red
   col[1]=(fc%65536)/256 'Green
   col[2]=fc/65536 'Blue
'Work out the difference between the forecolour and the backcolour
   sCol[0]=((bc%256)-col[0])/h 'Red
   sCol[1]=(((bc%65536)/256)-col[1])/h 'Green
   sCol[2]=((bc/65536)-col[2])/h 'Blue
'Do the vignette
for i=0 to h
	Line wn,x,y+i,x+w,y+i,RGB(int(col[0]),int(col[1]),int(col[2]))
'Adjust the base colour
for j=0 to 2
	col[j]+=sCol[j]
next j
next i
EndSub

SUB CheckPrinter()
	PRINTER_INFO_2 pi2
INT result,need=0,pEnum,I
MEMORY pBuffer
STRING prtName
	prtName=GETDEFAULTPRINTER
IF LEN(prtName)=0
	MESSAGEBOX(0,"There is no default printer installed","Printer error",0x0|0x30)
ELSE
' If need = 0, then the API returns the number of bytes needed
	EnumPrintersA(2,"",2,pBuffer,need,need,pEnum)
' Now allocate a memory buffer for the table to be returned
	ALLOCMEM pBuffer,1,need
	result=EnumPrintersA(2,"",2,pBuffer,need,need,pEnum)
' pEnum contains the number of udt's
FOR I=1 TO pEnum
'  copy from table to local udt
	READMEM pBuffer,I,pi2
if prtName=pi2.#<string>pPrinterName
IF (pi2.Attributes=1600) OR (pi2.Attributes=3648)
	MESSAGEBOX(0,pi2.#<string>pPrinterName+" does not appear to be switched on",pi2.#<string>pPrinterName,0x0|0x30)
endif
ENDIF
NEXT I
	FREEMEM pBuffer
ENDIF
ENDSUB