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| import math | |
| def calculate_polygons(startx, starty, endx, endy, radius): | |
| """ | |
| Calculate a grid of hexagon coordinates of the given radius | |
| given lower-left and upper-right coordinates | |
| Returns a list of lists containing 6 tuples of x, y point coordinates | |
| These can be used to construct valid regular hexagonal polygons | |
| You will probably want to use projected coordinates for this | |
| """ | |
| # calculate side length given radius | |
| sl = (2 * radius) * math.tan(math.pi / 6) | |
| # calculate radius for a given side-length | |
| # (a * (math.cos(math.pi / 6) / math.sin(math.pi / 6)) / 2) | |
| # see http://www.calculatorsoup.com/calculators/geometry-plane/polygon.php | |
| # calculate coordinates of the hexagon points | |
| # sin(30) | |
| p = sl * 0.5 | |
| b = sl * math.cos(math.radians(30)) | |
| w = b * 2 | |
| h = 2 * sl | |
| # offset start and end coordinates by hex widths and heights to guarantee coverage | |
| startx = startx - w | |
| starty = starty - h | |
| endx = endx + w | |
| endy = endy + h | |
| origx = startx | |
| origy = starty | |
| # offsets for moving along and up rows | |
| xoffset = b | |
| yoffset = 3 * p | |
| polygons = [] | |
| row = 1 | |
| counter = 0 | |
| while starty < endy: | |
| if row % 2 == 0: | |
| startx = origx + xoffset | |
| else: | |
| startx = origx | |
| while startx < endx: | |
| p1x = startx | |
| p1y = starty + p | |
| p2x = startx | |
| p2y = starty + (3 * p) | |
| p3x = startx + b | |
| p3y = starty + h | |
| p4x = startx + w | |
| p4y = starty + (3 * p) | |
| p5x = startx + w | |
| p5y = starty + p | |
| p6x = startx + b | |
| p6y = starty | |
| poly = [ | |
| (p1x, p1y), | |
| (p2x, p2y), | |
| (p3x, p3y), | |
| (p4x, p4y), | |
| (p5x, p5y), | |
| (p6x, p6y), | |
| (p1x, p1y)] | |
| polygons.append(poly) | |
| counter += 1 | |
| startx += w | |
| starty += yoffset | |
| row += 1 | |
| return polygons |
Hi ben. Of course, if you'd like to (please include me as an author for copyright purposes). However, note that http://postgis.net/docs/manual-dev/ST_HexagonGrid.html exists if your data are in a DB, also note that I published https://github.com/urschrei/hexcover a couple of years ago, which might be helpful.
awesome, thanks! didn't know about this postgis function, might useful in the future, similar to your other package. Atm I just needed a simple procedure that tiles a rectangle with hexagonal polygons, and this gist is the only thing I could find and was exactly what I was looking for. I just thought it'd be cool to have it easily accessible through PyPI. Of course I'll list you as the author. Cheers!
No prob. See also this package: https://github.com/alexkaz2/hexalattice
huh. How did I not find this one. thanks
hi @urschrei, thanks for sharing the code. I was unable to import hexcover after pip installing see colab notebook. Would we be able to use this Gist code as part of a larger project if we include you as the author?
Hi @cornhundred I've just uploaded 0.5.0 to pypi – try installing that, otherwise feel free to use the gist code.
thanks @urschrei, I'm still having trouble getting 0.5.0 to install (see updated Colab notebook). I'll go ahead with the Gist code - thanks again.
Can I refactor this into a PyPI package under the MIT License?