GIMP Version: 2.10.30
Operating System: Windows
OS Version: 10
GIMP Experience: New User

List any ERROR messages you received:
Error while executing script-fu-mockup:

Error: eval: unbound variable: script-fu-mockup

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Hi I am new to GIMP and I'm trying to use script-fu to make a simple script that takes the active layer and adjusts the perspective to fit some known coordinates but it's failing and I can't figure out why and was hoping someone could help. Here is the code


I think its got something to do with passing the layer id to (gimp-item-transform-perspective) I discovered the function called CAR (Contents of Address Register) and tried applying it to a variable after getting the id with (gimp-image-get-active-layer 1) this works in the console but wont work in the registered code.


Any hints on how i could get it to work in a registered script would be appreciated.

When you register a script, if the first two arguments of the script are in that order, and image and a drawable (so SF-IMAGE and SF-DRAWABLE in script-fu), they will be set to the current image and the image active drawable when script is called, and this is the normal way to register a script.

When you do so

* there is no need to call "gimp-image-get-active-layer".
* even if you do your get a proper image ID to use with it ("1" is the ID of the first image you load per Gimp session, all other images will have another ID).
* and this gives you a script that works on any image loaded in Gimp...

Thank you for responding but I am still confused.
I was following a youtube video called "GIMP Script-Fu 2: Write Your First Script" ( forum wont let me post link)



That is what I thought and why I didn't use "gimp-image-get-active-layer" in the registered script. I was trying to get it to trouble shoot and get it to work in the console and the only thing that works there is


The console wouldn't work either until I called (car) on the function for the active layer.

I rewrote this script but it still is failing with Execution error for 'Mockup':
Error: eval: unbound variable: script-fu-mockup



If you could point out in this code where I am going wrong it would be greatly appreciated.

Not a Scheme expert, I write my script in Python (but they work along the same principles). However I note that in the scripts that are installed with Gimp, the first arg to "script-fu-register" ("script-fu-mockup" in your case) is also the name of the function that implements the script, which is not true in your case ("mockup" != "script-fu-mockup").

Wow Thank you so much! I didn't realized you had to name the function a certain way. Now that you pointed it out it makes sense. Here is the working code with the name correct and I added (gimp-displays-flush):

Hi Bongobat. I started learning coding with "Scheme" but like ofnuts stated Python is so much easier and cleaner. I encourage you to learn Python. But if you has chosen to learn Scheme, one of our own member "Fencepost" has written a 3 parts scheming tutorials that is wonderful for new users who want to learn how to code. Download the folders with five PDF tutorials.

monsoonami on YouTube has several great tutorials as well.