Maps and storage

Hi everyone, I have a question about storage. Usually I upload a map, and then throw it into a game page, align it to the greed and game on. Of course while I do that the map is still in my library taking space. Today, I tried something. After loading a map into the pages and aligning it into the grid, I checked the storage ammount (this was a "heavy" map, 4.5MB) and I was at 49/100 MB. Then I deleted the map from my library, without deleting the page (where gaming occurs) and my storage went down to 45/100. Now I have the map loaded in my page for gaming and it is no longer taking any space. Can someone confirm this work like that, or will it end being removed from my pages? I have always been leaving the maps on the library taking space, but with this I can just load maps and then remove them. Cheers, Javier

That won't work.  You've removed the hosted image in your library, but your browser continues to show it from your local browser cache.  Anyone loading the map will get a broken image, and when it times out in your cache or you do a force refresh, it will be broken on your map page.

The Aaron said: That won't work.  You've removed the hosted image in your library, but your browser continues to show it from your local browser cache.  Anyone loading the map will get a broken image, and when it times out in your cache or you do a force refresh, it will be broken on your map page. Thanks a lot for the info. I tried as you mention and indeed it wont load for others. That means I need to rescale many of my maps, I have plenty up to 30MB. Does someone know what is a good map size to load into roll20 that still maintains good quality when zooming in for gaming? Also, is there a way to see how much storage is map takes. I can´t remember which ones take most to resize them.

I reduce map size considerably by saving them in .jpg format at 50% quality. They still look good.

There's not an easy way to find the size.  In game, you can select a map image, hit Z to zoom it up, right click and inspect it, then hover the URL and the browser will tell you how big it thinks it is:

I try to keep maps below 5mb (in case I share them with others it won't go over the Free level max size on art items).  If you have a large map image you might want to split it into multiple pieces. I usually aim for 140px per grid unit, and that is plenty for 'zooming in' quality in my experience. So a 20x40 map would be 2800x4200px. Also use .jpg whenever possible. A trick to add with that is to take the full size image and create a very low resolution version and lay that down first/behind the individual full resolution pieces, which helps do three things: 1. it'll help you align the entire map in the correct place and correct size; 2. whatever image on a page is the 'largest' in terms of grid dimensions is the one that will be shown as the thumbnail on the Page tab, and 3. there will be an 'initial image' that will be loaded for your players before the full resolution images.

Albert R. said: I reduce map size considerably by saving them in .jpg format at 50% quality. They still look good. This is the way, though you'll likely find you don't need to drop as far as 50%. The important thing for maps is always to change to jpg, and if it takes up more than 2MB, you probably need to reduce the quality further. Generally speaking, jpg and ~80% quality will get you excellent file size. If you are testing quality, always reopen your original file (assuming it's a PNG or similar lossless format), and resave as jpg. Do not save a jpg multiple times, as the quality is a multiplier - it will drop dramatically and drastically, and you'll get noticeably poor quality. But if you start from your original image, and save as jpg, dropping the quality further, you;ll be able to tweak to your hearts content. Remember for maps, you don't need photo-realistic quality - don't worry if you can see a drop in quality if you zoom in really close. Players are either looking at the tokens on top of the map, or are zoomed out and looking at the big picture.

Also, once an image is uploaded, it is converted into 4(?) different sizes of png for serving at different zoom levels. Your account storage however is only "charged" for the original upload file size. The ones Roll20 creates are frequently larger (byte size, not dimensions). A good rule of thumb is to save maps in jpg (to keep your storage down) at whatever compression still looks good to you. Ideally, 140px per grid should give you clean reproduction at most reasonable zoom levels. Quality is a very subjective matter of course. I will nearly always choose something a little under quality if the result means greater playability.

Jarren K. said: I try to keep maps below 5mb (in case I share them with others it won't go over the Free level max size on art items).  If you have a large map image you might want to split it into multiple pieces. I usually aim for 140px per grid unit, and that is plenty for 'zooming in' quality in my experience. So a 20x40 map would be 2800x4200px. Also use .jpg whenever possible. A trick to add with that is to take the full size image and create a very low resolution version and lay that down first/behind the individual full resolution pieces, which helps do three things: 1. it'll help you align the entire map in the correct place and correct size; 2. whatever image on a page is the 'largest' in terms of grid dimensions is the one that will be shown as the thumbnail on the Page tab, and 3. there will be an 'initial image' that will be loaded for your players before the full resolution images. keithcurtis said: Also, once an image is uploaded, it is converted into 4(?) different sizes of png for serving at different zoom levels. Your account storage however is only "charged" for the original upload file size. The ones Roll20 creates are frequently larger (byte size, not dimensions). A good rule of thumb is to save maps in jpg (to keep your storage down) at whatever compression still looks good to you. Ideally, 140px per grid should give you clean reproduction at most reasonable zoom levels. Quality is a very subjective matter of course. I will nearly always choose something a little under quality if the result means greater playability. Hi guys, a bit noob here. Could you explain what you mean 140px per grid. Is it 140x140pixel per square? and if so, why 140 over the 70 that comes by defaults? I have been using 70 always. I would love to know the difference. Many of the maps I upload have their own grid, others don´t but no idea how the 140px affect . Cheers,

70 pixels is the width of one grid square at 100% zoom. Most maps for modules are produced at this resolution because they are often quite large. For smaller maps, or if you personally feel you want a better looking map while zoomed in, you could save the original graphic at a higher multiple of 70. For example, at 200% zoom, 1 grid square equals 140 pixels (The grid displays larger at your zoom level, but your monitor is a physical object with a fixed resolution.) Many Marketplace tiles and maps are designed at higher resolution than 70 pixels per grid square, because the perception is that folks often play while zoomed in closer than 100%. In fact, tokens are often saved at 280 pixels (4x) or higher, because the players or gm really want to see the art clearly when previewed with the Z key. And tokens are more "prestige" art than maps. (We humans like perceiving faces and bodies). 70 dpi or 300 dpi is a misnomer for web graphics. There is no such thing as an "inch". The best term I've come up with to describe Roll20 image resolution is ppu, or "pixels per unit", a unit being one grid square.

Here's a quick demo. I used the same Mimic token and made 3 versions at 280x280px, 140x140px, and 70x70px. Here's zoomed out then zoomed in shots of all three at their 'full' size: Now here's zoomed out then zoomed in shots of all three when they are resized on the grid to one square:   Once the image is zoomed in, you can start to see that the 70x70 is slightly grainy, but there's virtually no difference between the 280x280 and 140x140, so that means that you're not getting any extra quality by keeping an image at a larger size.

keithcurtis said: 70 pixels is the width of one grid square at 100% zoom. Most maps for modules are produced at this resolution because they are often quite large. For smaller maps, or if you personally feel you want a better looking map while zoomed in, you could save the original graphic at a higher multiple of 70. For example, at 200% zoom, 1 grid square equals 140 pixels (The grid displays larger at your zoom level, but your monitor is a physical object with a fixed resolution.) Many Marketplace tiles and maps are designed at higher resolution than 70 pixels per grid square, because the perception is that folks often play while zoomed in closer than 100%. In fact, tokens are often saved at 280 pixels (4x) or higher, because the players or gm really want to see the art clearly when previewed with the Z key. And tokens are more "prestige" art than maps. (We humans like perceiving faces and bodies). 70 dpi or 300 dpi is a misnomer for web graphics. There is no such thing as an "inch". The best term I've come up with to describe Roll20 image resolution is ppu, or "pixels per unit", a unit being one grid square. Ok, that´s quite interesting. I Don´t fully understanding but I will mess around. Many of my maps come with their own squares, so I just snap the game grid to those squared. Would changing to 140 pixels make them look any better? What you mean is that in my mind at 140pixel grid, it would take 140 pixels of them, meaning what I want to fit in 4 squares would actually fit in 1 right? I have a 5k monitor, so resolution should not be an issue. Many maps are massive, for example the one I am using right now, I need it at 18% zoom to fit in fully in the screen. if I go into 90-100% zoom, that´s what I would be using for gaming. These maps, if you reduce them to be under 5MB, even as JPEG, that gives out a far less resolution.  Also, how can i easily make a map have squares exactly like the grid? Usually I put the map in the page in the background layer, I change it to is drawing, then manually or with align to grid function align it to the grid and thats it, but of course I need to make sure squares align.

Keep in mind that when I say 140 pixels per grid square, that's something you would account for in your graphics program. Roll20 is hard coded to display at 70 pixels per grid at 100%zoom. If you zoom in to 200%, you are going to see 140 pixels for every grid square. The map graphic hasn't changed, the page settings haven't changed, you are just looking at it at a larger size. Monitor resolution is probably not something to worry about. To get your maps to fit to the grid, count the squares. If your map is 30 x 30 units, then if you play at 100% zoom, your map will be displaying at 2100 x 2100 pixels. If your original map is 2100 pixels by 2100 pixels, then you are looking at it at native resolution (notwithstanding HD monitors, which compensate for this). If you want to keep the map pretty but small, saving it at this size would be ideal. If you think you are going to zoom in a lot, more resolution would be nice. In any case, if there is no border (grid squares on the map are edge to edge) then just set the number of squares on your page to equal the number of squares on your map. Drag the map to snap to the edges, and you are done. If your map has some margin, or the grids don't start at the edges, they you will either need to eyeball it into place as you have been doing, or resort to math.

keithcurtis said: Keep in mind that when I say 140 pixels per grid square, that's something you would account for in your graphics program. Roll20 is hard coded to display at 70 pixels per grid at 100%zoom. If you zoom in to 200%, you are going to see 140 pixels for every grid square. The map graphic hasn't changed, the page settings haven't changed, you are just looking at it at a larger size. Monitor resolution is probably not something to worry about. To get your maps to fit to the grid, count the squares. If your map is 30 x 30 units, then if you play at 100% zoom, your map will be displaying at 2100 x 2100 pixels. If your original map is 2100 pixels by 2100 pixels, then you are looking at it at native resolution (notwithstanding HD monitors, which compensate for this). If you want to keep the map pretty but small, saving it at this size would be ideal. If you think you are going to zoom in a lot, more resolution would be nice. In any case, if there is no border (grid squares on the map are edge to edge) then just set the number of squares on your page to equal the number of squares on your map. Drag the map to snap to the edges, and you are done. If your map has some margin, or the grids don't start at the edges, they you will either need to eyeball it into place as you have been doing, or resort to math. Ok, that threw me out. if I add a map to a page and align it to a grid at 100%zoom where I have 70 pixels per grid and it´s like you mentioned 2100x2100, even if I zoom in to 200% would that not still display 70 pixels per grid? My understanding when zooming is that each pixel becomes bigger, but withing each grid I still have the same map coverage I had at 100%. it is not like the 70 pixel grid covers more of the maps pixels. The good thing is that if as you mention, I set the gris to 140px, each grid square has double the ammount of pixels, so when zooming in it will always look better as there are more pixel each being half the size of a 70px grid? Everything else makes sense. Many thanks Keith and Jarren

Jarren K. said: I try to keep maps below 5mb (in case I share them with others it won't go over the Free level max size on art items).  If you have a large map image you might want to split it into multiple pieces. I usually aim for 140px per grid unit, and that is plenty for 'zooming in' quality in my experience. So a 20x40 map would be 2800x4200px. Also use .jpg whenever possible. A trick to add with that is to take the full size image and create a very low resolution version and lay that down first/behind the individual full resolution pieces, which helps do three things: 1. it'll help you align the entire map in the correct place and correct size; 2. whatever image on a page is the 'largest' in terms of grid dimensions is the one that will be shown as the thumbnail on the Page tab, and 3. there will be an 'initial image' that will be loaded for your players before the full resolution images. Most of the maps I have, comunity shared are JPG and well over 2MB, that why I needed for many to go down to 30% and such

keithcurtis said: Keep in mind that when I say 140 pixels per grid square, that's something you would account for in your graphics program. Roll20 is hard coded to display at 70 pixels per grid at 100%zoom. If you zoom in to 200%, you are going to see 140 pixels for every grid square. The map graphic hasn't changed, the page settings haven't changed, you are just looking at it at a larger size. Monitor resolution is probably not something to worry about. To get your maps to fit to the grid, count the squares. If your map is 30 x 30 units, then if you play at 100% zoom, your map will be displaying at 2100 x 2100 pixels. If your original map is 2100 pixels by 2100 pixels, then you are looking at it at native resolution (notwithstanding HD monitors, which compensate for this). If you want to keep the map pretty but small, saving it at this size would be ideal. If you think you are going to zoom in a lot, more resolution would be nice. In any case, if there is no border (grid squares on the map are edge to edge) then just set the number of squares on your page to equal the number of squares on your map. Drag the map to snap to the edges, and you are done. If your map has some margin, or the grids don't start at the edges, they you will either need to eyeball it into place as you have been doing, or resort to math. Hi againg. There is a thing that still confuses me, and sorry for so many questions, I have literaly never done any photo editing. I have a 73x70 map with squared that are 70px each giving us 5110x4900. This maps takes 2.6MB and was trying to reduce the size to 1ish MB. so Playing around I reduced the resolution to 2920x2800 giving me 40px per square and it take 1.1MB The thing is like you mention, roll20 is set at 70px per grid, so if my map has 40px grids, if I create the same ammount of squared on roll20 it is not going to fit in and I will need to resize internally in roll20, which will end up making me lose resolution if I try  to match them. How do I sort this out? is there a way to resize without taking px from each grid square? 

Javier B. said: This maps takes 2.6MB and was trying to reduce the size to 1ish MB. so Playing around I reduced the resolution to 2920x2800 giving me 40px per square and it take 1.1MB The thing is like you mention, roll20 is set at 70px per grid, so if my map has 40px grids, if I create the same ammount of squared on roll20 it is not going to fit in and I will need to resize internally in roll20, which will end up making me lose resolution if I try  to match them. How do I sort this out? is there a way to resize without taking px from each grid square?  Why are you resizing your maps to be so small? The free player size limit is 5MB, so there’s not much reason to stay so far below that down to 1mb.  If you’re concerned about load time for the image, I’d suggest keeping it at a higher resolution and cutting it into pieces. Then create a single low res version to put down first/behind the low res pieces to help align them (it will also make up the page tab image that way).

Jarren K. said: Why are you resizing your maps to be so small? The free player size limit is 5MB, so there’s not much reason to stay so far below that down to 1mb.  Probably because there are multiple replies earlier in the post suggesting small file sizes are better, and also because on Javier's opening post he said he was already at half his storage capacity so he is probably concerned about space. As a free user, he has to be concerned by such things. Javier B. said: How do I sort this out? is there a way to resize without taking px from each grid square? Yes, you can reduce the file size without changing resolution, by changing the file quality, and changing file type to *.jpg if using a different format. The way to do this varies with image editor. For simple edits like this, I use Irfanview. In that, open your image, then click CTRL+S to bring up the save dialog. Enter a file name different to the original (you don't want to replace the original), and in the Save as Type select JPG. Dont click save yet. To the right of the save dialog there is a form with a quality slider at the top. It will have a number like 80, 95, or 66, or could be anything less than 100. Drag it down to, say, 65, and then click save. Now you have a new copy of the file you can open and examine, which will be smaller than the original. If the quality is too low, try again - from the original image, and enter a bigger number, like say 75. And repeat till you get something you're happy with. The process will be different for each image editor, but the important things when changing to jpg: Always save a copy of the original When making new files, work from the original (and save a copy)

Javier B. said: Hi againg. There is a thing that still confuses me, and sorry for so many questions, I have literaly never done any photo editing. I have a 73x70 map with squared that are 70px each giving us 5110x4900. This maps takes 2.6MB and was trying to reduce the size to 1ish MB. so Playing around I reduced the resolution to 2920x2800 giving me 40px per square and it take 1.1MB The thing is like you mention, roll20 is set at 70px per grid, so if my map has 40px grids, if I create the same ammount of squared on roll20 it is not going to fit in and I will need to resize internally in roll20, which will end up making me lose resolution if I try  to match them. How do I sort this out? is there a way to resize without taking px from each grid square?  Simple answer, no. Ignoring HD monitors for the moment, 70px per unit(square) is the monitor resolution chosen by Roll20 for 100%zoom. It could be anything, but 70 is what they have chosen. Every graphic displayed is virtually resized on the fly to display at 70 ppu. This is true (though the value may be different) for every graphic everywhere that is told to fit into a certain dimension. You can't have an area on your monitor that has a different sized physical picture element (pixel). Everything is squeezed, stretched or displaying  at 1:1. If your graphic has 40 pixels per unit, and the display resolution on Roll20 is 70 pixels per unit, when you stretch it to fit the grid, your 40ppu pixels will be stretched to display at 175%. 1 grid has been stretched to fit 1 grid, but your 40 pixels have been stretched to cover 70 pixels worth of space. This is not a limitation of Roll20, but simply how computer graphics work. This is also not a bad thing. If Roll20 were locked into a 1:1 pixel display you wouldn't be able to zoom into or resize any graphics. Since no people play exclusively on 70ppu maps and 70ppu tokens at 100% all the time, the overwhelming majority of graphics you see are virtually re-sized. If you were to zoom into your 40ppu to 175%, you would see something approximating your original resolution. However, at 100% zoom, your map will be slightly blurry. This is a physical constraint of math. You can't make more with less. If you want to make the file size of your map smaller you have two options: reduce the resolution (as you have done), or increase the level of data compression (my recommendation). If you are saving your map as a jpeg (and you almost always should be), increase the compression (depending on your image editor, this might also be called decreasing the quality or somesuch). In any case, you are always making a compromise. Trying to achieve 1:1 pixel fidelity is a pointless quest. I've simplified the above by ignoring things like HD monitors and the way Roll20 modifies images for performance after they are uploaded (which you want them to do). The principles are sound, though.

Jarren K. said: Javier B. said: This maps takes 2.6MB and was trying to reduce the size to 1ish MB. so Playing around I reduced the resolution to 2920x2800 giving me 40px per square and it take 1.1MB The thing is like you mention, roll20 is set at 70px per grid, so if my map has 40px grids, if I create the same ammount of squared on roll20 it is not going to fit in and I will need to resize internally in roll20, which will end up making me lose resolution if I try  to match them. How do I sort this out? is there a way to resize without taking px from each grid square?  Why are you resizing your maps to be so small? The free player size limit is 5MB, so there’s not much reason to stay so far below that down to 1mb.  If you’re concerned about load time for the image, I’d suggest keeping it at a higher resolution and cutting it into pieces. Then create a single low res version to put down first/behind the low res pieces to help align them (it will also make up the page tab image that way). Main reason is to be able to load more images. If the take less, more of them I can have and maintain. If I leave them at 5MB I can only have 20, if I leave them at 1.5 ish I have have around 60.

keithcurtis said: Javier B. said: Hi againg. There is a thing that still confuses me, and sorry for so many questions, I have literaly never done any photo editing. I have a 73x70 map with squared that are 70px each giving us 5110x4900. This maps takes 2.6MB and was trying to reduce the size to 1ish MB. so Playing around I reduced the resolution to 2920x2800 giving me 40px per square and it take 1.1MB The thing is like you mention, roll20 is set at 70px per grid, so if my map has 40px grids, if I create the same ammount of squared on roll20 it is not going to fit in and I will need to resize internally in roll20, which will end up making me lose resolution if I try  to match them. How do I sort this out? is there a way to resize without taking px from each grid square?  Simple answer, no. Ignoring HD monitors for the moment, 70px per unit(square) is the monitor resolution chosen by Roll20 for 100%zoom. It could be anything, but 70 is what they have chosen. Every graphic displayed is virtually resized on the fly to display at 70 ppu. This is true (though the value may be different) for every graphic everywhere that is told to fit into a certain dimension. You can't have an area on your monitor that has a different sized physical picture element (pixel). Everything is squeezed, stretched or displaying  at 1:1. If your graphic has 40 pixels per unit, and the display resolution on Roll20 is 70 pixels per unit, when you stretch it to fit the grid, your 40ppu pixels will be stretched to display at 175%. 1 grid has been stretched to fit 1 grid, but your 40 pixels have been stretched to cover 70 pixels worth of space. This is not a limitation of Roll20, but simply how computer graphics work. This is also not a bad thing. If Roll20 were locked into a 1:1 pixel display you wouldn't be able to zoom into or resize any graphics. Since no people play exclusively on 70ppu maps and 70ppu tokens at 100% all the time, the overwhelming majority of graphics you see are virtually re-sized. If you were to zoom into your 40ppu to 175%, you would see something approximating your original resolution. However, at 100% zoom, your map will be slightly blurry. This is a physical constraint of math. You can't make more with less. If you want to make the file size of your map smaller you have two options: reduce the resolution (as you have done), or increase the level of data compression (my recommendation). If you are saving your map as a jpeg (and you almost always should be), increase the compression (depending on your image editor, this might also be called decreasing the quality or somesuch). In any case, you are always making a compromise. Trying to achieve 1:1 pixel fidelity is a pointless quest. I've simplified the above by ignoring things like HD monitors and the way Roll20 modifies images for performance after they are uploaded (which you want them to do). The principles are sound, though. Wow, Thanks again. I know I have to make a compromise. No issue with that, and that quality will be worse. All you mentioned is pretty much what was my understanding but you did bring up saving more compress or reducing quality, rather than resizing. I think that´s a good idea since if I resize to 40px but then need to stretch out to 70px so that grids match, the stretching will also reduce the quality. The other question that pops up from this and from the testing I am doing right now is. My 73x70 was uploaded to roll20. I created a new page, sized the page to 73x70 and went to that blank page, jumped into the background layer, and dragged my image into the page. As always the image looked tiny when it landed on my blank page so I have to resize it. I select a corner and drag it, and it turns out now my map is more like 70x74 than 73x70. Why could this happen?

It should snap to the nearest grid intersection. Hold down shift to turn off proportional scaling. Also, you can right click on the map image, choose "Advanced > Set Dimensions" and set the size programatically. Also, make sure you haven't swapped Horizontal for Vertical anywhere along the way.

keithcurtis said: It should snap to the nearest grid intersection. Hold down shift to turn off proportional scaling. Also, you can right click on the map image, choose "Advanced > Set Dimensions" and set the size programatically. Also, make sure you haven't swapped Horizontal for Vertical anywhere along the way. Thanks a lot. The dimension is so obvious yet I still missed it and it´s super useful. What does holding shift do. I don´t seem to notice anything

When you hold shift down, the proportions aren't maintained while scaling. You can make something long and skinny or short and fat.