Fog of War Map Primer

Several topics concerned with making and using maps as a GM

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Fog of War Map Primer

Postby UpQuark » 15 Jun 2013, 21:51

              Fog of War Map Primer

Some interest has been expressed in understanding layers to create usable maps for games utilizing Fog of War turns – where individual players receive a custom map exposing limited information about the world – this could be applied also to “Exploration Map” scenarios, where the overall map is unknown to the players.

I will demonstrate a basic methodology for this which can be applied in multiple graphic editing software which support layering and transparency. This process is one form of masking - modifying the view of a subordinate layer by means of an overlay (in this case, by completely covering a portion of it).

Most GM’s are already familiar with the basics, as it is common to use a base Master Map layer with unit (and possibly Retreated Unit) layers riding above it. This approach is simply an expansion of that methodology to provide custom maps with limitations on information based on visibility rules (which can vary – the Fog of War rules in The Haven are quite detailed and not simply all surrounding provinces).

First, the layer stack: layers appear as a stack, and when generating a flattened output are compressed top down. Any section of a layer which is transparent acts as a window to the layers beneath, and by managing the stacking order, it is relatively easy to accomplish a manageable layer scheme to quickly adjudicate turns and create custom maps for multiple players.

A basic stack should be (listed from top down (for n players):
    Province name layer
    Player x map
    Player x+1 map
    Player x+n map
    Active Units layer
    Retreated Units layer
    Visibility layer
    Master Map layer
    Storage Layers (hidden behind the Master layer for convenience – such as master storage of unit icons

Other layers can be used as required by the specific requirements of the game, including for GM tracking of hidden items. For example, the location of dead units for resurrection, or hidden units only visible to 1 player are good examples. I put the Province Name layer on top - it is transparent except for the province labels - rather than on the base map files (so, for example, the letters do not require individual fill and the province names are never covered by anything else, not even unit placement - it is important that Province Labels are always fully visible to the players, who are required to use these for their orders).

The control of visibility of each layer is utilized to make the individual player turns. Only 1 of the Player Maps should be active at any time, and the Visibility Layer is used only during adjudication (explained later). Custom layers may be exposed for particular players, or also used solely for GM tracking/adjudication.

I use many other layers for convenience in The Haven map – I have separated the map from the background graphics (to improve map viewing during adjudication by removing distracting graphics), and can take notes in sections of layers which are otherwise covered by overarching layers. For example, I utilize special layers for rivers, SCs, and textual labels (province names, both long and abbreviated)…As you get used to using layers for such a purpose, this will become more natural to you as you seek better methods to present and hold your data.

The key to any good map is a solid Baseline Map. This should be a complete line map, and each province should be able to be quickly colored and selected (using the Magic Wand tool) for deletion (to be made transparent).

    N.B.: When the Magic Wand or Paint Bucket is used to fill in a province, or to select a colored province for deletion of the fill (to make transparent – select with Magic Wand and hit Delete), ensure that the Tolerance Slider is sufficiently low enough (I like 15%) that only the desired color range will be selected/filled in. It is recommended to use solid fills (single color, i.e. no color variations) and solid lines (no aliased lines) to ensure accurate selection each time, and no residual effects as the map is altered over time. It should be possible to fill any space (land or sea) on your map without affecting in any way the lines of the line map or any other province. Test the line map thoroughly before proceeding, in every province. This Master Map file becomes the basis for the Master Map layer, as well as every individual player layer. They should be identical.

The Unit and Retreated Unit layers are completely transparent layers containing unit icons as required. Placing the active unit layer above the retreated unit layer allows quick transfer of retreating units to the Retreat Unit layer, and they can be displayed overlapped (and beneath) the newly occupying unit in a single province, to show the intermediate state of the retreating unit, prior to the release of the Retreat Adjustments turn.

Units.gif (1.24 KiB) Viewed 1117 times

This is an example of a Units layer – transparent except for the unit icons, positioned over the respective territories, individually selectable, movable, and available for copying (for adjustment phases).

Base_Map.gif (1.78 KiB) Viewed 1117 times

Some items to note in this excerpted base map – it shows standard land and sea colors (also used for rivers); it shows land bridges, specifically with a small break in the graphic to allow complete single click fill of the sea zones (all zones should be single click fill-able – so you don’t have small sections requiring separate fill, which is cumbersome and may be forgotten…); and shows SC markers with transparent zone around them.

The last is a feature I put into my map to maintain home SC coloring behind any home SC once the province is captured by another player – the transparent section will not be filled, and a layer beneath the Master layer has colored circles so these always have a circle around the SC marker showing the original SC ownership.

Player_Map.gif (3.99 KiB) Viewed 1117 times

The Player Map shows all territories colored with the exception of those which are visible to that particular player. The solidly filled spaces will cover all territory ownership fill and units not visible to the player in that turn report. Note again, only land and sea base colors are used on this map – no ownership color fill is used here (it is done on the Master Map below, and shows through).

All of the player’s units, and nearby enemy units, will also appear only in the exposed territories.

Visibility_Check.gif (1.58 KiB) Viewed 1117 times

I use a layer with a solid white background and a readily identifiable pattern (not to be confused with any color or other fill used in the maps) to expose as an underlying layer the transparent spaces on the individual player maps. For example, an empty non-SC territory exposed below a player map appears the same as a non-exposed, land colored space on the player map. To readily track from turn to turn which spaces are exposed, and which are simply painted over (not exposed) on the player map, turning on this layer during the visibility check following adjudication will quickly indicate those spaces which must be exposed as a result of moves during that turn – either exposing an underlying territory (selecting with the Magic Wand and hitting Delete) or coloring in (covering) the space on the Player map to cover up the underlying Master Map in that territory (painting with land or sea base color).

Visibility_View.gif (4.31 KiB) Viewed 1117 times

This shows a player turn map view with the Visibility Layer turned on, for example, showing both own unit and an opposing player's unit exposed.

Player_View.gif (3.47 KiB) Viewed 1117 times

This shows a final player view map, with the Visibility Layer turned off and exposing the underlying Master Layer colored fills for visible owned SC spaces. Note the colored fill in the SC marker nearby - it does not reflect current ownership which is unknown, only the starting SC ownership. Other markers nearby are colored with standard land fill - originally neutral.

Master_View.gif (3.68 KiB) Viewed 1117 times

This shows a view of the Master Map (with unit overlays) as it would appear for adjudication - therefore exposing all information.

There a few other key points to remember, especially as the number of layers grows in a file:

    1. Not all layers are exposed at any time – keep the Layers Tool open to show actively selected layers. Only 1 player layer should be active at any time, and none should be selected during adjudication (which is done on the Master Map and the Units & Retreated Units layers).

    2. Check each player layer with the Visibility Layer turned on following adjudication, and adjust each player layer accordingly. Then turn off the Visibility Layer.

    3. Remember to always ensure the layer you want to affect by a tool is the actively selected layer… The selection and fill tools affect the selected layer – which may be a layer below the layer you are viewing… you might be deleting a section of a layer below the visible layer, for example, as it may be selected as the active layer (even a layer turned off can be selected for modification…). Never worry – use the Undo key (and check the History Tool) to retract any mistaken modification. Layer discipline is key to quickly adjudicating turns.

Any questions or comments are welcome below, as are additional clarifications or other hints…
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Re: Fog of War Map Primer

Postby Petunia » 15 Jun 2013, 22:15

This is an ubelievably helpful post. Professional level work.
Any views expressed prior to Dec 2013 are solely my own and do not represent the site or its administration in any way.
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Exploration Map Primer

Postby UpQuark » 16 Jun 2013, 18:18

              Exploration Map Primer

As an addendum to the above Fog of War Map Primer, here is an alternative approach which will allow individual maps to be displayed for an Exploration Map game in which the overall map structure is not wished to be revealed until discovered, and without sharing the discoveries equally amongst all players (i.e. each player must discover the map for themselves).

This builds upon the Fog of War methodology, using the same basic layer structure. This is a further implementation of Masking implemented simply with layers (Masking is a very useful concept for other sorts of graphic manipulation, for more advanced stylistic features such as blends or embossification effects, and many add-ons are available for Paintdotnet which add other useful features - for example, angled text).

The differences:

    - The line map territory dividing lines shall be the same color as the "fog" area of the Player maps, which is not close to any fill colors in use; perhaps some form of grey.

    - The Player maps are made up of individually colored territories - with transparent lines as separators. Each Player map starts as the color of Fog and is slowly revealed as each territory is discovered.

In order to combine the 2 methods (Fog of War combined with Exploration), use both methodologies combined - with 2 Player maps active per Player, 1 for Fog of War as descibed above, and one for Exploration Fogginess. In the stack order, the Exploration Fog maps are placed ON TOP of the Territory Name layer - it is the very top series of layers.

So, start again with a Line Drawing for your map:

Explore_Line.gif (1.96 KiB) Viewed 1042 times

Note the lines have been all converted to grey. This map will become the Master Map, when the territories are filled with color (either base land/sea or ownership fill).

Explore_Master.gif (2.12 KiB) Viewed 1042 times

Make a copy of this map and fill with some other color easily distinguishable from grey.

Explore_Player_1.gif (1.96 KiB) Viewed 1042 times

Now using the magic wand, delete all of the boundary line markings - leaving a page with a transparent line map and only the spaces filled. This is actually easier by selecting all the filled zones and then using Ctrl-I (Edit > Invert Selection) to select only the boundaries.

Explore_Player_2.gif (1.95 KiB) Viewed 1042 times

Now change all fill to the Fog color of choice:

Explore_Player_3.gif (1.95 KiB) Viewed 1042 times

When superimposed over the Base (Master) Map, this is how it appears:

Explore_Player_4.gif (1.04 KiB) Viewed 1042 times

Make copies of this layer for every player (and it is always a good idea to back up every base layer you make for "emergency recoveries"...).

Explore_Player1.gif (1.51 KiB) Viewed 1042 times
Explore_Player2.gif (1.65 KiB) Viewed 1042 times
Explore_Player3.gif (1.55 KiB) Viewed 1042 times

Additional effort may be taken to further confuse the Players as to where they fit within the overall map, and even to hide the overall map size, as follows:

    1. Rotate Player maps - this is an easy intervention to give a different perspective to each player. Although map trading may occur, this adds a bit of "confusion" to the various maps based on orientation.

    2. Make a custom selection for each Player, as follows:
      When the Player's turn map is ready to be prepared (Player's Fog and Player map are turned on above the Units, Labels, SC markers, Units, Master map, etc), Flatten the image (Image > Flatten) and create a custom selection using the selection Tool. Here is an example of the same size selection used for 2 different sections of the map:

      Explore_Player1alt.gif (1.03 KiB) Viewed 1042 times
      Explore_Player2alt.gif (1023 Bytes) Viewed 1042 times

      Use Edit > Copy and then Edit > Paste into New Image to create a new file with that Player's Turn custom view.

      Save as the final format (.gif recommended).

      In the Master file, use the Undo button to reverse the Flatten process and repeat for each Player.
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Re: Fog of War Map Primer

Postby Pedros » 28 Jun 2013, 19:04

Thanks UpQuark. I asked for this kind of thing in the first place, but didn't expect anything as comprehensive as this!

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