dale@amiga.UUCP (Dale Luck) (05/09/87)
The SuperBitmap does not keep all the bits of the window in the allocated bitmap. If a line is drawn the is in the displayed portion of the bitmap, it is only drawn in the window and is not also drawn in the backup bitmap. When the application programmer needs to diddle with the bits with his own processor code, he may syncronize the backup bitmap with what maybe on the screen. 'SyncSBitMap' This will transfer the missing bits from the window in the the real superbitmap. The program can then do what ever it needs with those bits. When done, the program must call 'CopySBitMap' to get the new bits out to the displayed window. When dealing with intuition and all those users that insist on resizing the windows. You need to encase these calls with LockLayer calls. If Layer is a pointer to the layer associated with a superbitmap window then. LockLayer(Layer) Prevents corruption of Cliprects, etc. SyncSBitMap(Layer) CopyBits into master bitmap mungebits() You supply this. CopySBitMap(Layer) CopyBits back out to waiting window UnlockLayer(Layer) Resume normal operation Dale Luck, just one of the guys.