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MacOS 8.1

Win98

DOS

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+--------+-------------------------+-------------------------+--------+--------+
|00000000| 00 05 00 01 00 00 00 1a | 00 00 00 00 00 00 00 1a |........|........|
|00000010| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000020| 00 00 00 00 00 00 00 00 | 00 00 00 05 00 05 00 00 |........|........|
|00000030| 00 22 00 00 00 00 00 00 | 00 22 61 32 37 31 00 00 |."......|."a271..|
|00000040| 4e 16 00 00 20 19 00 00 | 00 00 00 00 00 00 00 00 |N... ...|........|
|00000050| 00 00 08 4e 65 77 4c 61 | 79 65 72 00 00 06 00 00 |...NewLa|yer.....|
|00000060| 00 00 00 db 00 00 00 00 | 00 00 00 db 00 00 00 14 |........|........|
|00000070| 03 c1 00 28 05 7e 00 ff | 00 00 00 00 00 00 0f a8 |...(.~..|........|
|00000080| 00 00 00 00 4e 1c 00 00 | 00 09 00 00 00 04 00 04 |....N...|........|
|00000090| ff fc ff fa 00 04 00 04 | ff fc ff fc 00 00 00 00 |........|........|
|000000a0| 00 00 00 00 83 00 0b 40 | 10 6b 53 63 72 65 65 6e |.......@|.kScreen|
|000000b0| 41 50 49 2f 31 39 39 39 | 36 00 06 47 65 6e 65 76 |API/1999|6..Genev|
|000000c0| 61 00 00 81 4f 53 45 72 | 72 20 4e 65 77 4c 61 79 |a...OSEr|r NewLay|
|000000d0| 65 72 28 4c 61 79 65 72 | 4f 62 6a 20 2a 6e 65 77 |er(Layer|Obj *new|
|000000e0| 4c 61 79 65 72 2c 20 4c | 61 79 65 72 4f 62 6a 20 |Layer, L|ayerObj |
|000000f0| 61 62 6f 76 65 4c 61 79 | 65 72 2c 20 4c 61 79 65 |aboveLay|er, Laye|
|00000100| 72 50 72 6f 63 20 74 68 | 65 50 72 6f 63 2c 20 47 |rProc th|eProc, G|
|00000110| 72 61 66 50 74 72 20 62 | 61 73 65 50 6f 72 74 2c |rafPtr b|asePort,|
|00000120| 20 73 68 6f 72 74 20 64 | 65 70 74 68 2c 20 75 6e | short d|epth, un|
|00000130| 73 69 67 6e 65 64 20 6c | 6f 6e 67 20 74 68 65 44 |signed l|ong theD|
|00000140| 61 74 61 29 3b 00 00 00 | 06 00 00 00 00 00 8a 00 |ata);...|........|
|00000150| 00 00 00 00 00 00 8a 00 | 00 00 00 03 c1 00 14 05 |........|........|
|00000160| 7e 00 ff 00 00 00 00 00 | 00 0f a8 00 00 00 00 4e |~.......|.......N|
|00000170| 1d 00 00 00 09 00 00 00 | 04 00 04 ff fc ff fa 00 |........|........|
|00000180| 04 00 04 ff fc ff fc 00 | 00 00 00 00 00 00 00 83 |........|........|
|00000190| 00 0b 40 14 6b 53 63 72 | 65 65 6e 4f 6e 65 4c 69 |..@.kScr|eenOneLi|
|000001a0| 6e 65 2f 31 39 39 39 37 | 00 06 47 65 6e 65 76 61 |ne/19997|..Geneva|
|000001b0| 00 00 2c 43 72 65 61 74 | 65 20 61 20 6c 61 79 65 |..,Creat|e a laye|
|000001c0| 72 20 6f 62 6a 65 63 74 | 20 66 6f 72 20 6f 66 66 |r object| for off|
|000001d0| 73 63 72 65 65 6e 20 64 | 72 61 77 69 6e 67 2e 00 |screen d|rawing..|
|000001e0| 00 00 06 00 00 00 00 00 | 44 00 00 00 00 00 00 00 |........|D.......|
|000001f0| 44 00 00 00 00 02 6b 04 | 40 02 6c 01 00 00 00 00 |D.....k.|@.l.....|
|00000200| 00 00 01 0f f1 00 00 00 | 00 00 00 00 00 00 0c 00 |........|........|
|00000210| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000220| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000230| 00 00 00 00 00 00 06 00 | 00 00 00 00 b9 00 00 00 |........|........|
|00000240| 00 00 00 00 b9 00 00 00 | 00 02 6b 02 28 03 c1 00 |........|..k.(...|
|00000250| ff 00 00 00 00 00 00 0f | a8 00 00 00 00 4e 16 00 |........|.....N..|
|00000260| 00 00 09 00 00 00 04 00 | 04 ff fc ff fa 00 04 00 |........|........|
|00000270| 04 ff fc ff fc 00 00 00 | 00 00 00 00 00 83 00 0b |........|........|
|00000280| 40 0b 6c 69 6e 6b 73 2f | 31 39 39 39 30 00 06 4d |@.links/|19990..M|
|00000290| 6f 6e 61 63 6f 00 00 4e | 61 31 42 38 2c 44 69 73 |onaco..N|a1B8,Dis|
|000002a0| 70 6f 73 65 54 68 69 73 | 41 6e 64 42 65 6c 6f 77 |poseThis|AndBelow|
|000002b0| 4c 61 79 65 72 73 0d 61 | 32 35 38 2c 49 6e 76 61 |Layers.a|258,Inva|
|000002c0| 6c 4c 61 79 65 72 0d 61 | 32 37 31 2c 4e 65 77 4c |lLayer.a|271,NewL|
|000002d0| 61 79 65 72 0d 61 32 45 | 30 2c 55 70 64 61 74 65 |ayer.a2E|0,Update|
|000002e0| 4c 61 79 65 72 0d 00 16 | 00 01 00 00 00 00 00 10 |Layer...|........|
|000002f0| 00 0c 00 01 00 00 00 00 | 00 00 00 00 00 00 00 06 |........|........|
|00000300| 00 00 00 00 3f 9c 00 00 | 00 00 00 00 3f 9c 00 00 |....?...|....?...|
|00000310| 00 00 00 00 75 30 02 6b | 01 ff 00 00 00 00 00 00 |....u0.k|........|
|00000320| 0f a8 00 00 00 00 4e 1f | 00 00 00 09 00 00 00 04 |......N.|........|
|00000330| 00 04 ff fc ff fa 00 04 | 00 04 ff fc ff fc 00 00 |........|........|
|00000340| 00 00 00 00 00 00 83 00 | 0b 40 0a 62 6f 64 79 2f |........|.@.body/|
|00000350| 31 39 39 39 39 00 06 4d | 6f 6e 61 63 6f 00 3e 1a |19999..M|onaco.>.|
|00000360| 4f 53 45 72 72 20 4e 65 | 77 4c 61 79 65 72 28 4c |OSErr Ne|wLayer(L|
|00000370| 61 79 65 72 4f 62 6a 20 | 2a 6e 65 77 4c 61 79 65 |ayerObj |*newLaye|
|00000380| 72 2c 20 4c 61 79 65 72 | 4f 62 6a 20 61 62 6f 76 |r, Layer|Obj abov|
|00000390| 65 4c 61 79 65 72 2c 20 | 4c 61 79 65 72 50 72 6f |eLayer, |LayerPro|
|000003a0| 63 20 74 68 65 50 72 6f | 63 2c 20 47 72 61 66 50 |c thePro|c, GrafP|
|000003b0| 74 72 20 62 61 73 65 50 | 6f 72 74 2c 20 73 68 6f |tr baseP|ort, sho|
|000003c0| 72 74 20 64 65 70 74 68 | 2c 20 75 6e 73 69 67 6e |rt depth|, unsign|
|000003d0| 65 64 20 6c 6f 6e 67 20 | 74 68 65 44 61 74 61 29 |ed long |theData)|
|000003e0| 3b 0d 0d 20 20 20 20 46 | 69 6c 65 3a 20 47 57 4c |;..    F|ile: GWL|
|000003f0| 61 79 65 72 73 2e 68 0d | 0d 49 4e 50 55 54 3a 20 |ayers.h.|.INPUT: |
|00000400| 20 61 62 6f 76 65 4c 61 | 79 65 72 20 20 20 20 20 | aboveLa|yer     |
|00000410| 20 54 68 69 73 20 69 73 | 20 74 68 65 20 6c 61 79 | This is| the lay|
|00000420| 65 72 20 61 62 6f 76 65 | 20 74 68 65 20 6c 61 79 |er above| the lay|
|00000430| 65 72 20 74 6f 20 63 72 | 65 61 74 65 2e 0d 20 20 |er to cr|eate..  |
|00000440| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00000450| 20 20 20 20 20 20 49 66 | 20 74 68 65 20 6c 61 79 |      If| the lay|
|00000460| 65 72 20 69 73 20 74 6f | 20 62 65 20 74 68 65 20 |er is to| be the |
|00000470| 74 6f 70 20 6c 61 79 65 | 72 2c 20 74 68 65 6e 20 |top laye|r, then |
|00000480| 70 61 73 73 20 6e 69 6c | 20 68 65 72 65 2e 0d 20 |pass nil| here.. |
|00000490| 20 20 20 20 20 20 20 74 | 68 65 50 72 6f 63 20 20 |       t|heProc  |
|000004a0| 20 20 20 20 20 20 20 54 | 68 65 20 70 72 6f 63 65 |       T|he proce|
|000004b0| 64 75 72 65 20 70 6f 69 | 6e 74 65 72 20 66 6f 72 |dure poi|nter for|
|000004c0| 20 74 68 65 20 6c 61 79 | 65 72 20 6f 62 6a 65 63 | the lay|er objec|
|000004d0| 74 2e 20 20 49 66 20 74 | 68 65 20 64 65 66 61 75 |t.  If t|he defau|
|000004e0| 6c 74 0d 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |lt.     |        |
|000004f0| 20 20 20 20 20 20 20 20 | 20 20 20 61 63 74 69 6f |        |   actio|
|00000500| 6e 73 20 61 72 65 20 61 | 6c 6c 20 6f 6b 61 79 2c |ns are a|ll okay,|
|00000510| 20 74 68 65 6e 20 70 61 | 73 73 20 69 6e 20 6e 69 | then pa|ss in ni|
|00000520| 6c 20 68 65 72 65 2e 0d | 20 20 20 20 20 20 20 20 |l here..|        |
|00000530| 62 61 73 65 50 6f 72 74 | 20 20 20 20 20 20 20 20 |basePort|        |
|00000540| 49 66 20 79 6f 75 20 70 | 61 73 73 20 69 6e 20 61 |If you p|ass in a|
|00000550| 20 70 6f 72 74 20 68 65 | 72 65 2c 20 74 68 65 6e | port he|re, then|
|00000560| 20 4e 65 77 4c 61 79 65 | 72 20 77 6f 6e d5 74 20 | NewLaye|r won.t |
|00000570| 63 72 65 61 74 65 20 6f | 6e 65 0d 20 20 20 20 20 |create o|ne.     |
|00000580| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|00000590| 20 20 20 66 6f 72 20 79 | 6f 75 2e 20 20 49 66 20 |   for y|ou.  If |
|000005a0| 6e 6f 20 70 6f 72 74 20 | 69 73 20 70 61 73 73 65 |no port |is passe|
|000005b0| 64 20 69 6e 2c 20 74 68 | 65 6e 20 69 74 20 77 69 |d in, th|en it wi|
|000005c0| 6c 6c 20 63 72 65 61 74 | 65 20 61 6e 0d 20 20 20 |ll creat|e an.   |
|000005d0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|000005e0| 20 20 20 20 20 6f 66 66 | 73 63 72 65 65 6e 20 47 |     off|screen G|
|000005f0| 57 6f 72 6c 64 20 28 6f | 72 20 70 6f 72 74 20 66 |World (o|r port f|
|00000600| 6f 72 20 73 79 73 74 65 | 6d 20 36 29 2c 20 62 61 |or syste|m 6), ba|
|00000610| 73 65 64 20 6f 6e 20 74 | 68 65 20 73 69 7a 65 2f |sed on t|he size/|
|00000620| 64 65 70 74 68 0d 20 20 | 20 20 20 20 20 20 20 20 |depth.  |        |
|00000630| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 6f 66 |        |      of|
|00000640| 20 74 68 65 20 6c 61 79 | 65 72 20 61 62 6f 76 65 | the lay|er above|
|00000650| 20 28 61 6e 64 20 73 6f | 6d 65 20 6f 74 68 65 72 | (and so|me other|
|00000660| 20 66 61 63 74 6f 72 73 | 29 2e 0d 20 20 20 20 20 | factors|)..     |
|00000670| 20 20 20 64 65 70 74 68 | 20 20 20 20 20 20 20 20 |   depth|        |
|00000680| 20 20 20 54 68 65 20 64 | 65 70 74 68 20 74 6f 20 |   The d|epth to |
|00000690| 63 72 65 61 74 65 20 74 | 68 65 20 6f 66 66 73 63 |create t|he offsc|
|000006a0| 72 65 65 6e 2e 20 20 49 | 66 20 30 20 69 73 20 70 |reen.  I|f 0 is p|
|000006b0| 61 73 73 65 64 20 69 6e | 2c 20 74 68 65 6e 0d 20 |assed in|, then. |
|000006c0| 20 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |        |        |
|000006d0| 20 20 20 20 20 20 20 74 | 68 65 20 64 65 70 74 68 |       t|he depth|
|000006e0| 20 69 73 20 62 61 73 65 | 64 20 6f 6e 20 74 68 65 | is base|d on the|
|000006f0| 20 61 62 6f 76 65 20 70 | 6f 72 74 2e 0d 20 20 20 | above p|ort..   |
|00000700| 20 20 20 20 20 74 68 65 | 44 61 74 61 20 20 20 20 |     the|Data    |
|00000710| 20 20 20 20 20 41 70 70 | 6c 69 63 61 74 69 6f 6e |     App|lication|
|00000720| 20 72 65 66 65 72 65 6e | 63 65 20 66 69 65 6c 64 | referen|ce field|
|00000730| 2e 20 20 53 74 6f 72 65 | 20 77 68 61 74 65 76 65 |.  Store| whateve|
|00000740| 72 20 79 6f 75 20 77 61 | 6e 74 20 68 65 72 65 2e |r you wa|nt here.|
|00000750| 0d 4f 55 54 50 55 54 3a | 20 6e 65 77 4c 61 79 65 |.OUTPUT:| newLaye|
|00000760| 72 20 20 20 20 20 20 20 | 20 49 66 20 73 75 63 63 |r       | If succ|
|00000770| 65 73 73 66 75 6c 2c 20 | 61 20 4c 61 79 65 72 4f |essful, |a LayerO|
|00000780| 62 6a 20 68 61 6e 64 6c | 65 20 77 69 6c 6c 20 62 |bj handl|e will b|
|00000790| 65 20 72 65 74 75 72 6e | 65 64 20 68 65 72 65 2e |e return|ed here.|
|000007a0| 0d 20 20 20 20 20 20 20 | 20 20 20 20 20 20 20 20 |.       |        |
|000007b0| 20 20 20 20 20 20 20 20 | 20 49 66 20 75 6e 73 75 |        | If unsu|
|000007c0| 63 63 65 73 73 66 75 6c | 2c 20 61 20 6e 69 6c 20 |ccessful|, a nil |
|000007d0| 77 69 6c 6c 20 62 65 20 | 72 65 74 75 72 6e 65 64 |will be |returned|
|000007e0| 20 68 65 72 65 2e 0d 52 | 45 53 55 4c 54 3a 20 4f | here..R|ESULT: O|
|000007f0| 53 45 72 72 20 20 20 20 | 20 20 20 20 20 20 20 54 |SErr    |       T|
|00000800| 68 65 20 6d 6f 73 74 20 | 6c 69 6b 65 6c 79 20 65 |he most |likely e|
|00000810| 72 72 6f 72 20 69 73 20 | 6d 65 6d 46 75 6c 6c 45 |rror is |memFullE|
|00000820| 72 72 2e 0d 0d 47 57 4c | 61 79 65 72 73 20 69 73 |rr...GWL|ayers is|
|00000830| 20 6d 65 61 6e 74 20 74 | 6f 20 73 69 6d 70 6c 69 | meant t|o simpli|
|00000840| 66 79 20 61 6e 64 20 73 | 74 61 6e 64 61 72 64 69 |fy and s|tandardi|
|00000850| 7a 65 20 6f 66 66 73 63 | 72 65 65 6e 20 64 72 61 |ze offsc|reen dra|
|00000860| 77 69 6e 67 20 69 6e 20 | 61 20 66 6c 65 78 69 62 |wing in |a flexib|
|00000870| 6c 65 20 77 61 79 2e 0d | 0d 4e 4f 54 45 3a 20 20 |le way..|.NOTE:  |
|00000880| 20 54 68 69 73 20 70 61 | 63 6b 61 67 65 20 77 61 | This pa|ckage wa|
|00000890| 73 20 6f 72 69 67 69 6e | 61 6c 6c 79 20 77 72 69 |s origin|ally wri|
|000008a0| 74 74 65 6e 20 66 6f 72 | 20 75 73 65 20 77 69 74 |tten for| use wit|
|000008b0| 68 20 47 57 6f 72 6c 64 | 73 2c 20 62 75 74 20 73 |h GWorld|s, but s|
|000008c0| 79 73 74 65 6d 20 36 0d | 20 20 20 20 20 20 20 20 |ystem 6.|        |
|000008d0| 73 75 70 70 6f 72 74 20 | 68 61 73 20 62 65 65 6e |support |has been|
|000008e0| 20 61 64 64 65 64 2e 20 | 20 59 6f 75 20 6e 6f 20 | added. | You no |
|000008f0| 6c 6f 6e 67 65 72 20 6e | 65 65 64 20 73 79 73 74 |longer n|eed syst|
|00000900| 65 6d 20 37 20 6f 72 20 | 63 6f 6c 6f 72 20 71 75 |em 7 or |color qu|
|00000910| 69 63 6b 64 72 61 77 0d | 20 20 20 20 20 20 20 20 |ickdraw.|        |
|00000920| 74 6f 20 75 73 65 20 74 | 68 69 73 20 70 61 63 6b |to use t|his pack|
|00000930| 61 67 65 2e 0d 0d 55 73 | 69 6e 67 20 6f 66 66 73 |age...Us|ing offs|
|00000940| 63 72 65 65 6e 20 47 57 | 6f 72 6c 64 73 20 61 6c |creen GW|orlds al|
|00000950| 6c 6f 77 73 20 61 70 70 | 6c 69 63 61 74 69 6f 6e |lows app|lication|
|00000960| 73 20 74 6f 20 61 63 68 | 69 65 76 65 20 76 65 72 |s to ach|ieve ver|
|00000970| 79 20 63 6c 65 61 6e 20 | 67 72 61 70 68 69 63 73 |y clean |graphics|
|00000980| 0d 65 66 66 65 63 74 73 | 20 74 68 61 74 20 61 72 |.effects| that ar|
|00000990| 65 20 6e 6f 74 20 70 6f | 73 73 69 62 6c 65 20 69 |e not po|ssible i|
|000009a0| 66 20 64 72 61 77 69 6e | 67 20 64 69 72 65 63 74 |f drawin|g direct|
|000009b0| 6c 79 20 74 6f 20 61 20 | 77 69 6e 64 6f 77 20 28 |ly to a |window (|
|000009c0| 6f 72 20 67 72 61 66 50 | 6f 72 74 29 2e 0d 49 6e |or grafP|ort)..In|
|000009d0| 20 6d 6f 73 74 20 63 61 | 73 65 73 2c 20 77 68 65 | most ca|ses, whe|
|000009e0| 6e 20 61 6e 20 69 6d 61 | 67 65 20 69 73 20 67 65 |n an ima|ge is ge|
|000009f0| 6e 65 72 61 74 65 64 20 | 69 6e 20 61 6e 20 6f 66 |nerated |in an of|
|00000a00| 66 73 63 72 65 65 6e 20 | 47 57 6f 72 6c 64 2c 20 |fscreen |GWorld, |
|00000a10| 74 68 61 74 20 69 6d 61 | 67 65 0d 77 69 6c 6c 20 |that ima|ge.will |
|00000a20| 65 6e 64 20 75 70 20 62 | 65 69 6e 67 20 64 69 73 |end up b|eing dis|
|00000a30| 70 6c 61 79 65 64 20 69 | 6e 20 61 20 77 69 6e 64 |played i|n a wind|
|00000a40| 6f 77 2e 0d 0d 54 68 69 | 73 20 72 65 6c 61 74 69 |ow...Thi|s relati|
|00000a50| 6f 6e 73 68 69 70 20 62 | 65 74 77 65 65 6e 20 6f |onship b|etween o|
|00000a60| 66 66 73 63 72 65 65 6e | 20 47 57 6f 72 6c 64 73 |ffscreen| GWorlds|
|00000a70| 20 61 6e 64 20 77 69 6e | 64 6f 77 73 20 6e 65 65 | and win|dows nee|
|00000a80| 64 73 20 74 6f 20 62 65 | 20 6d 61 6e 61 67 65 64 |ds to be| managed|
|00000a90| 2e 0d 49 6e 20 61 64 64 | 69 74 69 6f 6e 20 74 6f |..In add|ition to|
|00000aa0| 20 6f 6e 65 20 47 57 6f | 72 6c 64 20 72 65 6c 61 | one GWo|rld rela|
|00000ab0| 74 69 6e 67 20 74 6f 20 | 61 20 77 69 6e 64 6f 77 |ting to |a window|
|00000ac0| 2c 20 79 6f 75 20 6d 61 | 79 20 61 63 74 75 61 6c |, you ma|y actual|
|00000ad0| 6c 79 20 6e 65 65 64 20 | 6d 75 6c 74 69 70 6c 65 |ly need |multiple|
|00000ae0| 0d 47 57 6f 72 6c 64 73 | 20 74 6f 20 72 65 6c 61 |.GWorlds| to rela|
|00000af0| 74 65 20 74 6f 20 61 20 | 77 69 6e 64 6f 77 2e 20 |te to a |window. |
|00000b00| 20 4d 61 6e 79 20 65 66 | 66 65 63 74 73 20 64 65 | Many ef|fects de|
|00000b10| 6d 61 6e 64 20 6d 6f 72 | 65 20 74 68 61 6e 20 6f |mand mor|e than o|
|00000b20| 6e 65 20 6f 66 66 73 63 | 72 65 65 6e 0d 47 57 6f |ne offsc|reen.GWo|
|00000b30| 72 6c 64 2e 20 20 53 6d | 6f 6f 74 68 6c 79 20 64 |rld.  Sm|oothly d|
|00000b40| 72 61 67 67 69 6e 67 20 | 61 6e 20 69 6d 61 67 65 |ragging |an image|
|00000b50| 20 6f 76 65 72 20 61 20 | 62 61 63 6b 67 72 6f 75 | over a |backgrou|
|00000b60| 6e 64 20 69 73 20 6f 6e | 65 20 73 75 63 68 20 65 |nd is on|e such e|
|00000b70| 66 66 65 63 74 2e 0d 0d | 47 57 4c 61 79 65 72 73 |ffect...|GWLayers|
|00000b80| 2e 63 20 69 73 20 61 20 | 62 6c 6f 63 6b 20 6f 66 |.c is a |block of|
|00000b90| 20 63 6f 64 65 20 74 68 | 61 74 20 6d 61 6e 61 67 | code th|at manag|
|00000ba0| 65 73 20 74 68 65 20 6d | 6f 72 65 20 6d 75 6e 64 |es the m|ore mund|
|00000bb0| 61 6e 65 20 61 73 70 65 | 63 74 73 20 6f 66 20 68 |ane aspe|cts of h|
|00000bc0| 61 6e 64 6c 69 6e 67 20 | 6f 6e 65 0d 6f 72 20 6d |andling |one.or m|
|00000bd0| 6f 72 65 20 47 57 6f 72 | 6c 64 73 2e 20 20 47 57 |ore GWor|lds.  GW|
|00000be0| 4c 61 79 65 72 73 2e 63 | 20 67 69 76 65 73 20 79 |Layers.c| gives y|
|00000bf0| 6f 75 20 61 20 63 6f 6e | 73 69 73 74 65 6e 74 20 |ou a con|sistent |
|00000c00| 77 61 79 20 6f 66 20 72 | 65 6c 61 74 69 6e 67 20 |way of r|elating |
|00000c10| 47 57 6f 72 6c 64 73 2f | 77 69 6e 64 6f 77 73 0d |GWorlds/|windows.|
|00000c20| 74 6f 67 65 74 68 65 72 | 2e 0d 0d 41 20 63 6f 6d |together|...A com|
|00000c30| 6d 6f 6e 20 75 73 65 20 | 66 6f 72 20 6f 66 66 73 |mon use |for offs|
|00000c40| 63 72 65 65 6e 20 47 57 | 6f 72 6c 64 73 20 69 73 |creen GW|orlds is|
|00000c50| 20 74 6f 20 6d 6f 76 65 | 20 61 6e 20 6f 62 6a 65 | to move| an obje|
|00000c60| 63 74 20 61 72 6f 75 6e | 64 20 69 6e 20 61 20 77 |ct aroun|d in a w|
|00000c70| 69 6e 64 6f 77 20 73 6d | 6f 6f 74 68 6c 79 0d 6f |indow sm|oothly.o|
|00000c80| 76 65 72 20 61 20 62 61 | 63 6b 67 72 6f 75 6e 64 |ver a ba|ckground|
|00000c90| 2e 20 20 54 6f 20 61 63 | 63 6f 6d 70 6c 69 73 68 |.  To ac|complish|
|00000ca0| 20 74 68 69 73 2c 20 77 | 65 20 6e 65 65 64 20 33 | this, w|e need 3|
|00000cb0| 20 6c 61 79 65 72 73 2e | 0d 54 68 65 73 65 20 61 | layers.|.These a|
|00000cc0| 72 65 3a 0d 0d 31 29 20 | 20 54 68 65 20 77 69 6e |re:..1) | The win|
|00000cd0| 64 6f 77 20 6c 61 79 65 | 72 2e 20 20 54 68 69 73 |dow laye|r.  This|
|00000ce0| 20 69 73 20 74 68 65 20 | 74 6f 70 2d 6d 6f 73 74 | is the |top-most|
|00000cf0| 20 6c 61 79 65 72 20 69 | 6e 20 74 68 65 20 6c 61 | layer i|n the la|
|00000d00| 79 65 72 20 68 69 65 72 | 61 72 63 68 79 2e 20 20 |yer hier|archy.  |
|00000d10| 54 68 65 0d 20 20 20 20 | 74 6f 70 2d 6d 6f 73 74 |The.    |top-most|
|00000d20| 20 6c 61 79 65 72 20 69 | 73 20 74 79 70 69 63 61 | layer i|s typica|
|00000d30| 6c 6c 79 20 77 68 61 74 | 20 74 68 65 20 75 73 65 |lly what| the use|
|00000d40| 72 20 77 69 6c 6c 20 73 | 65 65 2c 20 61 6e 64 20 |r will s|ee, and |
|00000d50| 74 68 65 72 65 66 6f 72 | 65 20 63 6f 6d 6d 6f 6e |therefor|e common|
|00000d60| 6c 79 0d 20 20 20 20 69 | 73 20 61 20 77 69 6e 64 |ly.    i|s a wind|
|00000d70| 6f 77 20 6c 61 79 65 72 | 2e 20 20 4c 61 79 65 72 |ow layer|.  Layer|
|00000d80| 73 20 62 65 6c 6f 77 20 | 74 68 65 20 74 6f 70 2d |s below |the top-|
|00000d90| 6d 6f 73 74 20 61 72 65 | 20 74 79 70 69 63 61 6c |most are| typical|
|00000da0| 6c 79 20 6f 66 66 73 63 | 72 65 65 6e 0d 20 20 20 |ly offsc|reen.   |
|00000db0| 20 47 57 6f 72 6c 64 73 | 2e 0d 32 29 20 20 41 20 | GWorlds|..2)  A |
|00000dc0| 6d 69 64 64 6c 65 20 6c | 61 79 65 72 20 74 68 61 |middle l|ayer tha|
|00000dd0| 74 20 69 73 20 75 73 65 | 64 20 74 6f 20 61 70 70 |t is use|d to app|
|00000de0| 6c 79 20 74 68 65 20 6f | 62 6a 65 63 74 20 62 65 |ly the o|bject be|
|00000df0| 69 6e 67 20 6d 6f 76 65 | 64 20 74 6f 20 74 68 65 |ing move|d to the|
|00000e00| 0d 20 20 20 20 62 61 63 | 6b 67 72 6f 75 6e 64 20 |.    bac|kground |
|00000e10| 70 6c 75 73 20 72 65 6d | 6f 76 69 6e 67 20 74 68 |plus rem|oving th|
|00000e20| 65 20 6f 62 6a 65 63 74 | 20 66 72 6f 6d 20 74 68 |e object| from th|
|00000e30| 65 20 6f 6c 64 20 6c 6f | 63 61 74 69 6f 6e 2e 20 |e old lo|cation. |
|00000e40| 20 4f 6e 63 65 20 74 68 | 65 73 65 0d 20 20 20 20 | Once th|ese.    |
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+--------+-------------------------+-------------------------+--------+--------+