How do I transcribe a Kakuro into a Google Sheets?

Question

As other questions of mine mentioned, I have been slowly working through some PDF puzzle books. I will shortly come up on Kakuro puzzles. Here is an example from the Wikipedia article:

The parts where I enter solution-numbers into the grid are not a problem. Shading in entire cells is also simple. But, how can I do the half-cell triangles with either numbers or shading? Triangle shading is optional - if I can at least figure out some way to put in triangle numbers, I could enter some placeholder into the other part of the cell. Note that in all cases the same diagonal is used, so you do not have to worry about being flexible on which half-cell triangles are displayed.

Google Sheets is non-negotiable. I am not willing to use an inserted drawing, as suggested by a comment to the previous question. Within these constraints, how do I transcribe a Kakuro into a Google Sheets as simply as possible? Solutions which take up less cells of of the underlying Google Sheets are preferred.

Answer 1

Kakuro is still clear if the cells with the number clues had a black instead of a white background. In fact, many puzzles use a black background and it just happens that the one you shared has a white background. So, the triangle shading is unnecessary.

I will use the same example Kakuro which you shared and demonstrate how I would do it below.

Step 1

Resize the rows and columns into squares. Also, select all the cells and apply some styles that will be useful later:

1. Select a larger font size (it will be for the numbers that will fill up and solve the puzzle, e.g., 40).
2. Select a suitable font. (In my experience, Merriweather looks pretty good. I also apply Bold and a non-black color like blue.)
3. Add borders around the cells that will make up the puzzle grid.
4. Apply horizontal and vertical align.

Step 2

Apply the following styles to all cells that are black in the puzzle or that have number clues:

1. Black fill color
2. Smaller font size (e.g., 15)
3. White font color

(A fast way to do this is to apply these styles to one cell and then copy the cell to all needed cells.)

Step 3

Fill in the number clues. Do not use a backslash as the separator but instead use the ╲ character (U+2572). (Note that I have chosen the font Merriweather Bold because it aligns well with this character.)