Added legend

[alejandroloda]

Hi, I added a legend for the layered_view and some new colors.

[alejandroloda]

Looks like Travis can't open the font, but at least on my machine works, check if on yours you can run it, just create a simple model and: visualkeras.layered_view(model, legend=True) I mean, maybe I made something to allow it on the past, but I'm pretty sure that with font = ImageFont.truetype("arial.ttf", font_size) that comes from PIL should it works everywhere.

[paulgavrikov]

A quick google search tells me that you have to provide the full path to the font under Linux. And I believe I had similar issues when I tried to integrate fonts into visualkeras. I'd really want this module to be platform independant. So, a simple solution would be to not provide the font parameter at all and let PIL use the default or to add another parameter to layered_view to pass an ImageFont. Would you be able to integrate those changes?

[alejandroloda]

This change should works In case of not valid path for the font, the PIL default font will be load, but this one for now cannot be size change

[paulgavrikov]

I have reverted the merge, since this code breaks examples/generate_examples.py with legend=True:

Traceback (most recent call last):
  File "/home/paulgavrikov/Coding/git/visualkeras/examples/generate_examples.py", line 2, in <module>
    from examples import vgg16
  File "/home/paulgavrikov/Coding/git/visualkeras/examples/vgg16.py", line 75, in <module>
    visualkeras.layered_view(model, to_file='../figures/vgg16_color_map.png',
  File "/home/paulgavrikov/Coding/git/visualkeras/visualkeras/layered.py", line 208, in layered_view
    draw_text.text((box.x2 + 10, box.y1 - (font_size / 2)), layer, font=font, fill='black')
  File "/home/paulgavrikov/.local/lib/python3.8/site-packages/PIL/ImageDraw.py", line 289, in text
    if self._multiline_check(text):
  File "/home/paulgavrikov/.local/lib/python3.8/site-packages/PIL/ImageDraw.py", line 264, in _multiline_check
    return split_character in text
TypeError: argument of type 'type' is not iterable

Process finished with exit code 1

[paulgavrikov]

I also finally had some time to take a closer look. There are many hardcoded values that we have parameters for. Is your PR editable? If so I could push some changes later.

[alejandroloda]

Sorry I'm pretty new with PR, so I'm not sure if it is or isn't editable, but I see on your commit that you implemented my changes with the params that you mentioned

I made a try, and looks like its works, but I miss to have more colors by default, if you consider it, these are what I used ["#ffd166", "#ef476f", "#f95c3a", "#f456d4", "#06d6a0", "#35d049", "#118ab2", "#073b4c"]

But it's nice to have the legend working :)

[alejandroloda]

I see too that you could just equal cube_size to text_height, to avoid big cubes with the default font (that I estimated that is an 8 size) (lines 184-186)

Before:

After:

Also I see that due to use a set for layers_names, the order is loosen, so you could use a list instead, and on line 191 do:

seen = set()
layer_names = [x for x in layer_names if not (x in seen or seen.add(x))]

In this case don't forget to upgrade lines 51 (list for set) and 68 (append for add) to keep the compatibility

[paulgavrikov]

There should be a checkbox when creating the PR to set it editable, but I am no expert either. Your changes are pretty much in the master. I'll change cube_size to text_height and I'll fix the legend order (with a slightly different trick) - thanks for the heads up! The proposed colors however don't really look nice on the VGG16 test (under /examples) and honestly, I don't have the time to play around with them for too long. I believe I got the original colors from a generator that attempted to maximize the distinguishability but I can no longer find the website. Anyways, I agree we should expand the number of colors in the wheel.

[alejandroloda]

Pretty nice :) I will be waiting for the pip