Reading bitmaps from files

Bitmaps can be read from files by sending the readBitmapFile:widthReturn:heightReturn:bitmapReturn:xHotReturn:yHotReturn: message to any CgDrawable. Parameters passed to the method include the file name and ReturnParameter objects for the width, height, the actual bitmap, and the x and y hot spot location. The value of any ReturnParameter object can be accessed by sending it the value message.

| error wReturn hReturn bReturn xReturn yReturn bitmap |

error := CgWindow default

readBitmapFile: 'brick'

widthReturn: (wReturn := ReturnParameter new)

heightReturn: (hReturn := ReturnParameter new)

bitmapReturn: (bReturn := ReturnParameter new)

xHotReturn: (xReturn := ReturnParameter new)

yHotReturn: (yReturn := ReturnParameter new).

error = 0

ifTrue: [

Transcript cr; show: 'File read successful. ',

'Bitmap width: ', wReturn value printString,

', height: ', hReturn value printString,

', hotspot: ', (xReturn value @ yReturn value) printString.

bitmap := bReturn value.

bitmap freePixmap]

ifFalse: [Transcript nextPutAll: 'File read error: ',

error printString; cr].