Picture Datatype DitherHiColour variable.

While diagnosing some missing file problems in several programs, I noticed that my ENVARC:Classes/DataTypes/Picture directory has been replaced by a file with the same name. The picture.datatype looks for the environmental variable DitherHiColour in the Classes/Datatypes/Picture environmental directory and fails now that the directory is a file. When I noticed this problem I tested several image intensive programs with Snoopy and found that a number of programs waste a lot of CPU time with picture.datatype failing to find the DitherHiColour variable. Was the picture directory replaced with a file by one of the recent OS4+ installers on everybody's system or did I somehow mess this up myself?

@xenic

I compared my OS4.1 backed uo partition with my current OS4.1 update 2
- there is no envarc:classes/datatypes/ directory in OS4.1
- there is no envarc:classes/datatypes/picture directory in neither one
In Update 2 the datatypes subdirectory contains the picture file
In both sys:classes/datatypes contains the same datatype files

@xenic

Classes/Datatypes/picture has the value 1 here. Never touched it, because it's not descriped in the docs.

@ZeroG
Quote:
It is described in the OS 3.9 docs for picture.datatype. The picture datatype checks for the environmental variable "DitherHiColour" (which is set to either 0 or 1) in the ENV:classes/datatypes/picture directory. If you run Snoopy and start a program that uses datatype image loading (like OWB) you will see that picture datatype looks for the DitherHiColour variable and fails. If you check the picture.datype with a Hex reader, you will see the text: "classes/datatypes/picture/DitherHiColour". It appears that somewhere in the transition from OS 3.9 to OS 4.x that variable in ENVARC: got erroniously changed to classes/datatypes/picture (a file named picture instead of a directory). I'll have to check and see if the variable changes anything in OS4.x but this should be fixed;either by installing the correct environmental variable or eliminating it from picture.datatype.

@xenic

I might be completely wrong here, but isn't AmigaOS4 based on AmigaOS3.1 and not 3.9?

@MoonSire

Quote:
You are not completely wrong

@MoonSire
Quote:
ZeroG mentioned that the picture.datatype environmental variable isn't mentioned in the OS4.x documentation. I responded that it is mentioned in the OS 3.9 documentation; not that OS4.x is entirely based on OS 3.9. However, at least some of OS4.x is based on OS 3.9. Take a look at "SYS:Utilities/IconEdit" and you will see that it is still a 68k (OS3) program. That's because it was introduced in OS 3.5/3.9 and Hyperion doesn't have the sourcecode. I don't know whether the "DitherHiColour" environmental variable was added in the OS 3.1 picture.datatype or the OS 3.9 picture.datatype. However, if it had been introduced in OS 3.1 I think that "Colour" (British spelling) would have been spelled "Color" (American spelling).
The point is that OS 4.x picture.datype is looking for the "picture" directory to find the "DitherHiColour" variable and that the directory has been changed to a file named "picture". Either picture.datatype needs to be changed not to look for the DitherHiColour variable or the picture file needs to be changed back to a directory.

@xenic

Quote:
I believe that the DitherHiColour variable/file was and is supposed to be inside the picture directory. I would guess it's a glitch in some installation program, either the OS4.1 update [1|2] installer or some third-party installer, which accidentally created the file instead.

Best regards,

Niels