PICT Comments
Volume Number: 4
Issue Number: 6
Column Tag: Resource Roundup
Comments About PICTs 
By Joel West, Palomar Software, Inc., MacTutor Contributing Editor
Joel West is the author of the best selling MPW book titled Programming with
Macintosh Programmer’s Workshop. He is also the principle in Palomar Software,
which produced the popular Colorizer DA and recently, the Pict Detective utility. In
this column he continues his Resource Roundup with some expert insights into PICT
resources.
PICTs
This month’s focus will be on PICT resources, handles and documents. These
QuickDraw pictures are the lingua franca of Macintosh graphics, the common ground
between diverse applications.
As I’m always fond of emphasizing, software developers (yes, that means you!)
must support compatibility and standards to keep the users and marketing types happy.
Whatever other graphics formats you prefer, the standard user interface requires you
to support PICTs in some form or another.
Besides, PICTs are the native format of QuickDraw, a mere transcription of the
various QD calls. In practical terms, PICTs are what you get for free with your
Macintosh graphics, so if you can display it on the screen, you can record it in a PICT.
Now while I’m big on standards, I’m not so dogmatic as to ignore the reality that
PICTs are often the lowest common denominator, such as when you’re writing a
complex PostScript-based program. Still, that doesn’t mean you should ignore PICTs,
or make them look like heck--since that’s also what you’ll get on the many
non-PostScript printers.
What kind are there?
Our Mac world is divided into two classes of people: those own Macintosh II’s, and
the impoverished masses. (Before anyone starts flaming, let me say that I’m writing
this with the SE on my desk at Palomar, and with my Plus at home, since other people
are using my Mac II.)
Anyway, there are the original, classic, or “PICT-1” pictures that were defined
with the Macintosh 128, and unchanged by the Plus and SE. Any Macintosh can
generate these and display them accurately.
The Macintosh II can also generate and display new, color, or “PICT-2” pictures
that require Color QuickDraw. The main differences are that you get more than 8
colors, and you can have color bit images.
Fig. 1 Our sample PICT object parsed with Pict Detective
You can use a PICT-2 on a Plus or an SE, thanks to a clever DrawPicture() patch
in System 4.1 and later. (See “Sleuthing the New System File” in the August 1987
edition of Resource Roundup.). The patch draws a PICT-1 approximation of the color
picture. Unfortunately, in doing so, the patch throws all the interesting information
on the floor.
There is a reasonable way to preserve this information (Palomar would be glad to
provide it to any developer upon request), but interest in doing this seems to be
Referenced by (2):