Color Pictures in Basic Graphics Ports
You can use Color QuickDraw drawing commands to create a color picture on a computer supporting Color QuickDraw. If the user were to cut the picture and paste it into an application that draws into a basic graphics port, the picture would lose some detail, but should be sufficient for most purposes. This is how basic QuickDraw in System 7 draws an extended version 2 or version 2 picture into a basic graphics port:
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QuickDraw maps foreground and background colors to those most closely approximated in basic QuickDraw's eight-color system.
-
QuickDraw draws pixel patterns created with the
MakeRGBPat
procedure as bit patterns having approximately the same luminance as the pixel patterns.
-
QuickDraw replaces other color patterns with the bit pattern contained in the
pat1Data
field of the
PixPat
record. (The
pat1Data
field is initialized to 50 percent gray if the pattern is created with the
NewPixPat
function; this field is initialized from a
'ppat'
resource if the pattern is retrieved with the
GetPixPat
function.)
-
QuickDraw converts the pixel image to a bit image.
-
QuickDraw ignores the values set by the
HiliteColor
and
OpColor
procedures, as well as any changes made to the
chExtra
and
pnLocHFrac
fields of the original
CGrafPort
record.
© 1997 Apple Computer, Inc.Previous | Chapter Top | Chapter Contents | Next