Prepare project

We will use any python 3 version so we can use Pillow package. This is the most used package for Image manipulation with python.

If you use pyCharm, open Interpreter Settings and install pillow package. If you use different IDE, you would need to use pip install pillow via console.

💡 I recommend to create a new virtual environment so you don't clutter you main space. But you can also uninstall it later.

Convert icon.png

Next, add any icon as a test file in the same folder with your python script. Once we make the code work for one image, we will adjust to go through the whole extension.

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Now place any icon.png next to your python file and let's write the following code:

Here is what's going on:

• Open image with Image class from pillow library

• Define Color to replace with

• Load Image Data (list of pixels)

• Replace visible pixels (Keep Transparency)

• Save Updated Image as icon.dark.png

Refactor to a function

Before going further, let's convert our code into a function to make it easier to work with.

Get All Icons

Now we need to scale and find all icons in our extension. There are many ways to do that, I will use os.walk function.

Here is a simple function:

os.walk will provide:

• root - the provided root path

• dirs - all nested folders

• files - list of all files in all nested folders

So we will use files and filter those ending with icon.png.

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yield - creates a generator from the function. Instead of returning whole list at once, it will be giving one item at the time.

Create Dark Icons

And lastly, you can convert all your icons for the dark theme by calling these 2 functions.

And now congratulations. If you followed correctly, you should have dark-theme icons in pyRevit. Here is how my EF-Tools looks like:

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P.S.

Don't forget to watch the full tutorial here: