WIP: Line of Sight Generator for Fantasy Grounds

[GEONE]

https://geone.tv/FGU LoS Generator

NOTE: This requires you to have or create a mask for the walls of your map. A mask is a simple black and white image, where the walls (or non-walkable areas) are black and the rest of the map (the walkable areas) is white. Example: https://i.imgur.com/u6CbysY.jpg. This tool will not work correctly if you upload a regular coloured map or a map with a black and white filter. Some map makers provide these masks for you, but they are also quite simple to create in an image editing software. The mask image must be the same size as the image you are using in Fantasy Grounds.

Hello, all!
I finally got around to sitting down and writing my own generator for LoS/dynamic lighting definitions. The best part is that it's 100% free and works locally inside your browser! The images you upload aren't sent over the internet, and it isn't gated behind a paywall.

This tool is very WIP, I literally wrote it in a day and a half, and I haven't tested it very much. It can take a black & white image mask and generate an XML file containing occluders that can be used in Fantasy Grounds. If you've ever used Dungen.app you'll be familiar with the concept. You can change several variables like wall offset, expansion/contraction, accuracy, and you can even change the wall type of each polygon (wall, terrain, door, etc)! After you download the XML file, you just need to open your campaign database file, find the image record and layer you want to add the walls to, and copy/paste the occluders in. The UX still needs some polish, but I hope it helps some people.

The tool is hosted online at https://geone.tv/FGU LoS Generator

It uses PyScript because I know Python much better than JavaScript, so it can take a few seconds to load the virtual environment PyScript runs in when you first visit the page.

---

How to use the generated XML file

The XML file it generates will look something like this. Copy all of the text in the file.

						<occluders>
							<occluder>
								<id>0</id>
								<points>91,208,108,228,88,243,73,226</points>
								<closed />
							</occluder>
							<occluder>
								<id>1</id>
								<points>-91,208,-75,230,-94,242,-108,219</points>
								<closed />
							</occluder>
							<occluder>
								<id>2</id>
								<points>96,25,112,44,90,65,71,42</points>
								<closed />
							</occluder>
						</occluders>

You need to locate the image record layer in your campaign's db.xml file and paste it in there

<images>
	<image>
		<id-00001>
			<image type="image">
				<uselos>on</uselos>
				<uselighting>on</uselighting>
				<layers>
					<layer>
						<name>Dungeon.jpg</name>
						<id>0</id>
						<parentid>10</parentid>
						<type>image</type>
						<bitmap>campaign/images/Dungeons/Dungeon.jpg</bitmap>
						THIS IS WHERE YOU PASTE THE COPIED TEXT
					</layer>
				</layers>
			</image>
			<name type="string">Example Dungeon</name>
		</id-00001>
	<image>
</images>

The end result will look something like this

<images>
	<image>
		<id-00001>
			<image type="image">
				<uselos>on</uselos>
				<uselighting>on</uselighting>
				<layers>
					<layer>
						<name>Dungeon.jpg</name>
						<id>0</id>
						<parentid>10</parentid>
						<type>image</type>
						<bitmap>campaign/images/Dungeons/Dungeon.jpg</bitmap>
						<occluders>
							<occluder>
								<id>0</id>
								<points>91,208,108,228,88,243,73,226</points>
								<closed />
							</occluder>
							<occluder>
								<id>1</id>
								<points>-91,208,-75,230,-94,242,-108,219</points>
								<closed />
							</occluder>
							<occluder>
								<id>2</id>
								<points>96,25,112,44,90,65,71,42</points>
								<closed />
							</occluder>
						</occluders>
					</layer>
				</layers>
			</image>
			<name type="string">Example Dungeon</name>
		</id-00001>
	<image>
</images>

EDIT: First round of bug fixing is done. If you tried it before and encountered an issue, give it another try and see if it's been fixed.
EDIT 2: More bug fixes and added additional visualization features like vertex points that match FGU's style.

[Jiminimonka]

Nice. I will take a look this weekend!

[LordEntrails]

Thanks for sharing. Glad to see you have an accuracy setting. Personally I keep my segments on caves to be at least one grid in length. Helps with performance,

[ddavison]

Nice job.

Instead of copying and pasting it directly into the db.xml, you can also create what we call a side-load XML file. Just match the image name and change the extension to .xml and place it next to the image file. When you drag it in fro the assets folder, it will automatically apply that to the image record in FG.

If you set the walls directly on the wall edges, you can set a peek-through setting of 0.2 or 0.3 and it will show a little bit behind the lines for 20% of a grid square or 30% of a grid square depending on what peek-through setting you used.

To create an example file to reference,
1. open any map in FG and unlock it.
2. right-click on the layer with LOS and choose Export Metadata

[spoofer]

This is amazing.

Your image shows a png image map. However, when I tried with a png, it froze. The same image as a jpg worked in about 1 second.

[GEONE]

This is amazing.

Your image shows a png image map. However, when I tried with a png, it froze. The same image as a jpg worked in about 1 second.

That's odd. I use pngs most of the time when using this tool because jpgs can have artifacts that I don't want messing with the generator. Was your png perhaps a renamed webp or something?

[spoofer]

I was using this website. It was really working well for me. However, now it no longer loads. It gets stuck on downloading pyodide-dev. Please fix! Please please please!!!

[GEONE]

I was using this website. It was really working well for me. However, now it no longer loads. It gets stuck on downloading pyodide-dev. Please fix! Please please please!!!

I'm trying to figure out why it stopped working. Everything is locally hosted and nothing has changed as far as I'm aware. Might take some time to get things working again.

[Tempered7]

I tried to test it with my old maps (not the B&W ones program accepts I think) but I have zero understanding of image stuff, and failed. This was when you first posted it.

I tried it now with the image you provided in OP and it gave me this error:
losgen-error.png

Settings are exactly like the image in OP.
Hope it helps.

[GEONE]

I tried to test it with my old maps (not the B&W ones program accepts I think) but I have zero understanding of image stuff, and failed. This was when you first posted it.

I tried it now with the image you provided in OP and it gave me this error:
losgen-error.png

Settings are exactly like the image in OP.
Hope it helps.

There's gonna be a lot of errors and weirdness because I'm messing around with the live build right now.

I think I fixed it by downgrading PyScript to a 2022 version. No idea why the version I was using suddenly stopped working, especially since it's a local version of PyScript that's being served by my website.

Polygon index selection appears to be broken now though.