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Does Roll20 changing the image aspect ratio during the upload?

Hi, I have a very specific question. During the Corona-crises in Europe it is not possible to have regular p&p sessions (Pathfinder 1e). Now I have written my campaign for an offline game but decided to convert it into an online one. As preparation for my players, I have designed maps by hand (they have a grid) and I don't want to redraw them on PC. So I had a very simple idea, my handrwan maps have 30x24 squares, note this fixed the aspect ratio of the image. Then I scanned them and loaded them up into my campaign, where I declared the size of the virtual sheet as 30x24 squares (which corresponds to 2100x1680 pixels on the roll20 grid). From my scan, I have an Image with AxB pixels (where A <2100p and B<1680p). The idea was to upload this image to roll20 and just stretch it to the boundaries of the virtual sheet, then I should get a map with 30x24 squares and perfectly matching grids (the one one the scan and the one of roll20). But it happened that the uploaded image does not fit into the created grid of the virtual sheet. So I have the suspicion that the aspect ratio gets blurred during the upload of an image. Does everyone know a solution to this problem or have a workaround for this issue. Thanks a lot Cheers 
1585074445
The Aaron
Roll20 Production Team
API Scripter
This is a common problem with digital scans/photos of hand drawn maps.&nbsp; There are a few things you can do.&nbsp; The easiest is just to turn off the grid and not worry about snapping, let players put their tokens on the table like they would in the physical world.&nbsp; We often turn off the grid in our games even when it's 100% digital from start to finish. Align to your map to the grid:&nbsp; <a href="https://roll20.zendesk.com/hc/en-us/articles/360039243994-Aligning-Maps" rel="nofollow">https://roll20.zendesk.com/hc/en-us/articles/360039243994-Aligning-Maps</a> &nbsp; There's a whole lot of info on how to do that, but the basics are you zoom in to see a 3x3 drawn map grid section clearly, right click and choose Align to Grid, mark that 3x3 grid, and the system will resize it so that those fit to the grid. One problem you may run into is that you get aligned on one end, but it ends up off on the other.&nbsp; This happens when either your picture's aspect was slightly off when you took it, or your starting graph paper wasn't precise with it's spacing, etc.&nbsp; There isn't much you can do about that short of remastering your image in a painting program.&nbsp; What usually works is to get it as close as you can and then set the grid color to transparent.&nbsp; you'll get the snapping you want, but you wan't have the distraction of the mismatched grid lines, and it's generally not far off enough that you will even notice it at that point.
Tanks for your answer, I will try it the next time. But for information, I have encountered a workaround after multiple hours of try and error, where you can achieve a perfect match of your grids. The problem I encountered was that roll20 rounds up or down the image size to an integer number of grid cells, for example, an image with aspect ratio 4:3 gets rounded to a 3x2 cells grid image. So what can one do now? Just go to the image properties and resize your grid cells size of one axis to the closest candidate integer number which is a multiple of your aspect ratio (e.g for "width") and let the other axis be a few fields larger than needed. What happens then is a little bit of magic, when you stretch the image in one direction to this boundary it suddenly reshapes and you have perfectly matched grid distances in one direction (besides from measuring errors when you cut out your scan image). Now squeeze or enlarge the remaining side of the image to the closest integer candidate of a multiple of the aspect ration and the same magic happens again. The result is perfect match grids on arbitrarily sized hand-drawn (or pdf files, etc.) maps and the grid on roll20. I can't tell why this is working, it has to come from the image processing code from the backend of the homepage but it definitely works. I have done this with 9 maps of different sizes.&nbsp; I just wanted to post my solution here for the sake of completeness for other gamemasters they trying to do the same. But many thanks for your response and also a good solution. Cheers
1585092880
The Aaron
Roll20 Production Team
API Scripter
Cool!&nbsp;&nbsp;