NOTE: This Technical Note has been
retired. Please see the Technical Notes
page for current documentation.|
Features Not Supported in Mac OS 8.0
Following is a list of key features that are currently available in QuickDraw GX 1.1.3/1.1.5 that will no longer be available to developers under the GXGraphics 1.1.6 strategy:
Overview of the GXGraphics Extension
The GXGraphics extension is a system extension that adds powerful graphics and typographic capabilities to your user's Macintosh without requiring the full QuickDraw GX package to be installed on your user's machine. The extension that we are currently licensing and distributing, GXGraphics 1.1.3, covers all QuickDraw GX graphics and typography functionality up to and including QuickDraw GX version 1.1.3.
The GXGraphics 1.1.3 extension contains GX graphics and typography, but does not
contain GX Printing. There are stubs for the GX Printing calls in
The GXGraphics 1.1.6 release contains GX graphics and typography, but will no longer have the printing stubs available. This extension is being tested and released for Mac OS 8.0. See Table 1 for more specific details.
Table 1: Differences in the QuickDraw GX Releases
|QuickDraw GX||1.1.3, 1.1.5||QuickDraw GX||* qdgx (obsolete)|
|GX Printing||* pmgr|
|GX Graphics||* grfx|
|Collections Mgr||* cltn|
* APIs are exported and available
Since the GX printing architecture will no longer be supported for Mac OS, any software that does not already have a solution using classic QuickDraw printing will need to be updated. For the majority of applications, the recommended solution for Mac OS 8.0 is to use the QuickTime compression/decompression mechanism for imaging QuickDraw GX data. The basic technique is to encapsulate the QuickDraw GX image in a compressed data format using the object flattening functions from QuickDraw GX. Once the compressed image data is created, it may be passed to the QuickDraw GX codec and drawn using the QuickTime image compression functions or embedded within a QuickDraw picture and drawn using the DrawPicture function. In either case, the compressed data is passed to the the low-level QuickDraw drawing routines through the StdPix bottleneck routine. StdPix decompresses the data using the QuickDraw GX codec and passes the decompressed data to the bitsProc bottleneck routine when rendering the image.
LaserWriter drivers starting with version 8.3 recognize compressed data that may
be drawn using QuickTime, like QuickDraw GX flattened objects. For Mac OS 8.0, the
LaserWriter driver has been modified to render the QuickDraw GX data at the device
resolution of the printer. When despooling, the printer driver changes the resolution
of the offscreen drawing port and uses the QuicDraw GX codec to rasterize the compressed data.
The QuickDraw printer drivers from Apple render the compressed data during spooling and use
the resolution of the active graphics port. Application developers may wish to use the device
resolution commands of the
General Changes For All Applications
The sample code for this Technote includes updated versions of three QuickDraw GX
Specific Changes Required Based on Level of Support
Here is an outline of the changes GX applications will need to make. They are outlined according to the level of GX support.
GX Unaware (no knowledge of GX)
Additional ChangesCustom Page formatting:
It is important to note, that even today - on System 7.5.x - it is possible for an application using GXGraphics 1.1.x to print using the classic printing mechanism described above.
GX Printing Extension Changes
Printing extensions have been used for a wide variety of things in the history of GXPrinting. However, despite their potential for optimizing printing from certain kinds of applications, they have never been developed or used to their full potential by many developers. Unfortunately, under the new GX model , GX extensions are no longer available. Some of the functionality that developers have used GX extensions for can be rolled into classic applications or drivers, but that will have to be determined by the developer on a case-by-case basis.
GX Printer Driver Changes
Under the new GX model, GX printer drivers will no longer be supported. There is no transition plan for these drivers.
Classic Printer Driver Changes
In the world of GXGraphics 1.1.6 it will be desirable to print GX objects to classic printer
Under the new GX architecture, there is no way to author PDD documents. Also, SimpleText will not display PDD's under QuickDraw GX 1.1.6. You should convert PDD files to a different format, such as Adobe Acrobat PDF files, before attempting to use them with Mac OS 8 or QuickDraw GX 1.1.6.
Incompatibilities and Limitations
This section describes the known incompatibilities and limitations, and their solutions for the GXGraphics 1.1.6 extension:
Where to Get GXGraphics 1.1.6 and How to License it
The GXGraphics 1.1.6 extension:
By simply following the above steps, you should easily be able to convert your GX applications into a viewable applications that your users will be able to use without having the complete GX extension installed.
"The All-New LaserWriter Driver Version 8.4", in develop 27 by Dave Polaschek.
"Printing Images Faster With Data Compression", in develop 24 by David Gelphman.
"Meet PrGeneral, the Trap That Makes the Most of the Printing Manager", in develop 3 by Pete Alexander.
A Print Loop That Cares-- The Sequel, technote 1092 by Ingrid Kelly.
Adding Items to the Printing Manager's Dialogs, Technote 1080 by Ingrid Kelly and Dave Polaschek.
GXGraphics extension, available for download by clicking here.
New GX PPC Libraries, available for download by clicking here.
Sample Code, available for download by clicking here.
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