From http://www.jwz.org/xscreensaver/xscreensaver-5.36.tar.gz

[xscreensaver] / README.hacking

diff --git a/README.hacking b/README.hacking
index a716196295ac94730d664b85e1ce45ddff88d9e0..3cceb5773c0be4ea083002a2a73d604d23b7e9d2 100644 (file)
--- a/README.hacking
+++ b/README.hacking
@@ -139,15 +139,18 @@ Programming Tips
   - Don't make assumptions about the depth of the display, or whether it
     is colormapped.  You must allocate all your colors explicitly: do not
     assume you can construct an RGB value and use that as a pixel value
   - Don't make assumptions about the depth of the display, or whether it
     is colormapped.  You must allocate all your colors explicitly: do not
     assume you can construct an RGB value and use that as a pixel value

-    directly.  Use the utility routines provided by "utils/colors.h" to
-    simplify color allocation.
+    directly.  In particular, you can't make assumptions about whether
+    pixels are RGB, RGBA, ARGB, ABGR, or even whether they are 32, 24,
+    16 or 8 bits.  Use the utility routines provided by "utils/colors.h"
+    to simplify color allocation.

 
   - It is better to eliminate flicker by double-buffering to a Pixmap
     than by erasing and re-drawing objects.  Do not use drawing tricks
     involving XOR.
 
 
   - It is better to eliminate flicker by double-buffering to a Pixmap
     than by erasing and re-drawing objects.  Do not use drawing tricks
     involving XOR.
 

-  - If you use double-buffering, have a resource to turn it off. (MacOS
-    has double-buffering built in, so you'd be triple-buffering.)
+  - If you use double-buffering, have a resource to turn it off. (MacOS,
+    iOS and Android have double-buffering built in, so you'd end up
+    triple-buffering.)

 
   - Understand the differences between Pixmaps and XImages, and keep in
     mind which operations are happening in client memory and which are in
 
   - Understand the differences between Pixmaps and XImages, and keep in
     mind which operations are happening in client memory and which are in


@@ -160,20 +163,16 @@ Programming Tips
 
 
 ==========================================================================
 
 
 ==========================================================================

-The MacOS X Port
+MacOS, iOS and Android

 ==========================================================================
 
   Though XScreenSaver started its life as an X11 program, it also now runs
 ==========================================================================
 
   Though XScreenSaver started its life as an X11 program, it also now runs

-  on MacOS X.  If you do your development on an X11 system, and follow the
+  on MacOS, iOS and Android, due to a maniacal collection of compatibility
+  shims.  If you do your development on an X11 system, and follow the

   usual XScreenSaver APIs, you shouldn't need to do anything special for
   usual XScreenSaver APIs, you shouldn't need to do anything special for

-  it to also work on MacOS.
+  it to also work on MacOS and on phones.

 
 

-  The preprocessor macro HAVE_COCOA will be defined when being compiled in
-  a MacOS (Cocoa/Quartz) environment, and will be undefined when compiling
-  against "real" Xlib.
-
-  To compile on MacOS, use the XCode project included in the source
-  distribution.  You shouldn't need to have X11 installed, and shouldn't
-  need to run "configure" first.
+  See the READMEs in the OSX/ and android/ directories for instructions on
+  compiling for those platforms.

 
 ==========================================================================
 
 ==========================================================================