Generation stops at almost last download

[UltraDanHR]

For big downloads (~90k), generation stops at almost last download, both for albedo and heightmap

[manticorp]

Hi, I saw your previous message about huge generations - it might actually be a memory issue. What size are the images you're trying to generate? A 90k pixel square image will take up ~ 30GB in memory which might not be allowed by Chrome - you might have to do it in smaller portions and then combine after the fact. For the heightmaps, turning off normalisation might help.

[UltraDanHR]

Basically this:
https://manticorp.github.io/unrealheightmap/#latitude/39.3002991861503/longitude/-2.548828125/zoom/5/outputzoom/13/width/81920/height/71680

[manticorp]

Hmm - I will look into this in more detail when I have some time in the new year.

I've just sat down at my computer and tried the generation myself, and the URL you provided is trying to create a 81920 x 71680 pixel image.

That's a 5,872 megapixel image!!

So, it's first got to download each of the 90,201 tiles which are ~120kb each (which is 10.8GB of download, for a start):

It will then need to load all those images into memory, and create an output image in memory as a HTML canvas.

Uncompressed, 5,872 MP in 8 bit RBG is going to be ~ 17GB.

So at least 34GB of memory is required for an albedo image, and I think a bit more for the heightmap as it loads it into a UINT16 array.

Overall, the memory requirements of creating such a large image might be the stumbling block, and beyond the scale of this application.

My suggestions would be either:

• Lower the output zoom to reduce the resolution. Even one or two levels down might help.
• Export in sections and combine together in a more refined software such as Photoshop or Photopea.

I will have a think as to how we can modify the application for extremely large generations, but it's unlikely that there will be an automatic solution because of browser limitations. It would probably require being able to stream directly to files, which is note widely supported.

[manticorp]

I'll leave this issue open, because it would be awesome to do super large exports like this!

[UltraDanHR]

So I gave a thought about this, this needs some steps:

• Option to freeze cursor in place
• Sometimes you want to check certain terrain in the area you've selected, but this moves the cursor
• Divide area by cells, select one area as focus
• This will allow to export big maps, one area at a time, without spending a whole day selecting squares and trying to match these
• Remember which area you've downloaded
• I'm not sure if this will even be worth the effort to be done, basically store in cookies or cache what has been downloaded
• Maybe manual user input?
• User can pretty much just use a Google sheets, hence previous comments