Plugins usually don't work, how do I debug?

Question

I am trying to write a plugin that will create a bitmap font. However, this is very frustrating to learn... while I am not familiar with python, it is not that hard to pick up and have not had problems with it outside of GIMP.

Copied some of the code from: https://github.com/sole/snippets/blob/master/gimp/generate_bitmap_font/sole_generate_bitmap_font.py and from http://gimpbook.com/scripting/

Does work:

#!/usr/bin/env python

# Hello World in GIMP Python

from gimpfu import *

def create_font(cwidth, cheight, font, size, color) :

    #Set GLOBAL
    char_begin = 32
    char_end = 127
    num_chars = char_end - char_begin

    # Figure out total width & height
    """twidth = cwidth * 10
    theight = cheight * 10

    # Create Image
    img = gimp.Image(cwidth * 10, cheight * 10, RGB)
    img.disable_undo()

    # Save the current foreground color:
    pdb.gimp_context_push()

    # Set the text color & background color
    gimp.set_foreground(color)
    gimp.set_background(0, 0, 0)

    # Create All Layers & Position Accordingly
    for i in range(char_begin, char_end):
        string = '%c' % i
        offset = i - char_begin

        x_pos = offset * cwidth
        y_pos = offset * cheight

        text_layer = pdb.gimp_text_fontname(img, None, x_pos, y_pos, string, -1, False, size, PIXELS, font)

        gimp.progress_update(float(offset) / float(num_chars))

    pdb.gimp_image_flatten(img)

    img.enable_undo()

    # Create a new image window
    gimp.Display(img)
    # Show the new image window
    gimp.displays_flush()

    # Restore the old foreground color:
    pdb.gimp_context_pop()"""

register(
    "python_fu_bitmap_font",
    "Bitmap Font",
    "Create a new bitmap font",
    "*****",
    "*****",
    "2013",
    "Bitmap Font (Py)...",
    "",      # Create a new image, don't work on an existing one
    [
        (PF_SPINNER, "cwidth", "Cell Width", 24, (1, 3000, 1)),
        (PF_SPINNER, "cheight", "Cell Height", 51, (1, 3000, 1)),
        (PF_FONT, "font", "Font face", "Consolas"),
        (PF_SPINNER, "size", "Font size", 50, (1, 3000, 1)),
        (PF_COLOR, "color", "Text color", (1.0, 0.0, 0.0))
    ],
    [],
    create_font, menu="<Image>/File/Create")

main()

Does not work:

#!/usr/bin/env python

# Hello World in GIMP Python

from gimpfu import *

def create_font(cwidth, cheight, font, size, color) :

    #Set GLOBAL
    char_begin = 32
    char_end = 127
    num_chars = char_end - char_begin

    # Figure out total width & height
    twidth = cwidth * 10
    theight = cheight * 10

    # Create Image
    """img = gimp.Image(cwidth * 10, cheight * 10, RGB)
    img.disable_undo()

    # Save the current foreground color:
    pdb.gimp_context_push()

    # Set the text color & background color
    gimp.set_foreground(color)
    gimp.set_background(0, 0, 0)

    # Create All Layers & Position Accordingly
    for i in range(char_begin, char_end):
        string = '%c' % i
        offset = i - char_begin

        x_pos = offset * cwidth
        y_pos = offset * cheight

        text_layer = pdb.gimp_text_fontname(img, None, x_pos, y_pos, string, -1, False, size, PIXELS, font)

        gimp.progress_update(float(offset) / float(num_chars))

    pdb.gimp_image_flatten(img)

    img.enable_undo()

    # Create a new image window
    gimp.Display(img)
    # Show the new image window
    gimp.displays_flush()

    # Restore the old foreground color:
    pdb.gimp_context_pop()"""

register(
    "python_fu_bitmap_font",
    "Bitmap Font",
    "Create a new bitmap font",
    "*****",
    "*****",
    "2013",
    "Bitmap Font (Py)...",
    "",      # Create a new image, don't work on an existing one
    [
        (PF_SPINNER, "cwidth", "Cell Width", 24, (1, 3000, 1)),
        (PF_SPINNER, "cheight", "Cell Height", 51, (1, 3000, 1)),
        (PF_FONT, "font", "Font face", "Consolas"),
        (PF_SPINNER, "size", "Font size", 50, (1, 3000, 1)),
        (PF_COLOR, "color", "Text color", (1.0, 0.0, 0.0))
    ],
    [],
    create_font, menu="<Image>/File/Create")

main()

It seems that the after changing the beginning comment from line 15 to line 19 that everything goes to hell. And to be honest, I am not even sure how to debug this. I tried using the console under Filters>Python-Fu>Console - however this kept telling me line 1 was the issue... which I think we can all agree is not the case.

I tried running pieces of this code in a python script and works perfectly fine.

What should I do?

Answer 1

First of all, try to remove the shebang at line 1.

Then something that has nothing to with the actual problem, but why are you creating such a big string?

# Create Image
"""img = gimp.Image(cwidth * 10, cheight * 10, RGB)
img.disable_undo()

# Save the current foreground color:
pdb.gimp_context_push()

# Set the text color & background color
gimp.set_foreground(color)
gimp.set_background(0, 0, 0)

# Create All Layers & Position Accordingly
for i in range(char_begin, char_end):
    string = '%c' % i
    offset = i - char_begin

    x_pos = offset * cwidth
    y_pos = offset * cheight

    text_layer = pdb.gimp_text_fontname(img, None, x_pos, y_pos, string, -1, False, size, PIXELS, font)

    gimp.progress_update(float(offset) / float(num_chars))

pdb.gimp_image_flatten(img)

img.enable_undo()

# Create a new image window
gimp.Display(img)
# Show the new image window
gimp.displays_flush()

# Restore the old foreground color:
pdb.gimp_context_pop()"""

Is this your way to comment out the code?