Overview
The Atmosphere is a collection of variables that are used to modify how a map looks and feels, including elements such as Sun, Wind, Sky, Atmospheric Fog, Clouds, Fog of War, Unit Visibility, and Colour Grading,
This guide covers what these atmosphere tools are, where they are located, and how to work with them to modify your map.
How Atmosphere Works
To create the atmosphere in Age of Empires IV, the Sun lights not only the ground, but the Sky (Atmospheric Scattering) and the Clouds, which also light the ground some more. The ground then also reflects some colour back onto the clouds, which in turn, add some colour back to the terrain.
Essentially the entire map is a system of interconnected bouncing light that has the overall effect of changing the feeling or mood of the map.
To further break it down:
- The Sun & the Sky provide the biggest influences on the brightness and warmth of a map's lighting. These should be set together first and have the most dramatic effect.
- The Sun Angle can also have a big impact on the warmth and feel of a map's lighting, simulating dawn, midday, and dusk.
- Ambient map lighting can provide additional colour in the form of bounce lighting from below, which and can also affect the clouds, which in turn also slightly tints the terrain.
Unit Light Sources
It is worth noting that many units, objects, and buildings in Age of Empires IV possess effects that emit light on their surrounding environments, such as torches, campfires, and blacksmith forges.
These effects are less noticeable in high ambient light settings, but lower light atmospheres can cause these effects to be more noticeable and can dramatically change how the game looks and feels, creating the options for amazing-looking dusk, nighttime, eerily-misty, and dawn scenarios.
Atmospheric Toggles
The Atmospheric Toggles control which atmospheric elements are currently enabled in your map.
To open these settings, go to the Scenario Tree and select Atmosphere.
The atmosphere toggles will then appear in the Properties panel.
These settings either enable or disable he various atmospheric effects, including:
- Sun Enabled: Toggles on and off the sun, which reflects off snow and water.
- Soldier Light Enabled: Toggles on or off unit-based light sources such as torches
- Sun Cloud Enabled: Enables clouds drifting across the map, casting shadows on the land and water
- Ambient Enabled: Enables ambient light in the map
- Fog Enabled: Toggles on and off fog on the map
- Exposure Enabled: Functionality not available in the current version of the content editor.
Atmosphere Effects
There are many types of atmosphere effects in Age of Empires IV, such as sun, fog, ambient lighting, wind, and more.
To access the atmosphere settings for your map, navigate to: Scenario Tree > Atmosphere > Default
The Properties panel will then show all the current settings for the atmosphere in your level.
This panel contains 14 possible atmospheric settings, which can be combined to create a unique look.
These functions are covered in the sections below.
Combining Atmospheres
You can combine multiple atmospheres in a single map to show at different times, such as foggy morning, clear sunny afternoon, and cool night.
Having multiple atmospheres allows you to blend between them via script triggers in game. See Scripting for Crafted Maps for more information.
Atmospheric Debug Objects
When working with atmosphere changes such as sun and clouds, it can be useful to have a reference object to see the effect of your changes. This is achieved by using the Debug Spheres.
These objects are perfectly round, reflective spheres that allow you to see the surrounding landscape as well as the sky and horizon. These three spheres include a diffuse object, a normal object, and an ultra-reflective object.
To spawn the spheres onto your map, go to the Object Browser and search for "Sphere."
Then, drag the spheres_small object onto your map. Once spawned, you may wish to increase their size so they are easier to see.
You can find additional debug objects by going to the Object Browser and navigating to: Templates > Art > Debug
Here you will find additional objects such as material balls and torus shapes that can give you valuable feedback on the effect your atmosphere has on various materials.
Atmosphere Tools
When adjusting your map's atmosphere, the base look of your map is a combination of your map's Sun + Ambient + Sky. These elements are the biggest contributors to how lighting on your map looks and should be adjusted first and together.
Sun
Sun is the main light on your map and the only light in the game that can cast shadows.
The sun can be any colour you wish, but for a realistic effect it should lean toward bright white, orange, or yellow with an intensity of around 9.5 to 10.
Darker sun colours will require higher intensity than lighter-coloured ones.
- Time of Day: Functionality not available in the current version of the content editor.
- Sun Diffuse Colour: Controls the colour and transparency of the light emitted by the sun.
- Sun Diffuse Intensity: Controls the intensity of the light emitted by the sun. Default value is 10.
- Shadow Intensity: The opacity of the shadows cased by the sun. Default intensity is 1, but can be lowered to create a more subtle effect.
- Shadow Penumbra Size: Functionality not available in the current version of the content editor.
- Shadow Penumbra Distance: Functionality not available in the current version of the content editor.
- Sun Orbit: Controls the rotational position of the sun.
- Sun Angle: Controls the height of the the sun, affecting the angle it casts shadows at.
- Shadow Near Clip Pullback: Functionality not available in the current version of the content editor.
- Shadow Far Clip Distance: Functionality not available in the current version of the content editor.
Ambient
The Ambient of a map is an effect that involves a combination of the Sky and the image you load for the Map Name.
The Sky lights most things on the map that are upward-facing, such as the tops of buildings, trees, and units.
The ambient Map Image bounces the light off the map itself to light objects from below and should generally match the terrain colour.
SAO stands for "Screen-space Ambient Occlusion." This controls shadows in corners and crevices primarily noticeable on the shadow side, not in the sun.
- Map Name: The image that controls the general style and colour palette of the ambient light. Choose from the options available.
- Ambient Light Orbit Relative to Sunlight Orbit: Toggle sun-based ambient light on or off.
- Light Rotation: Controls the rotation of the ambient material lighting.
- Scale: Overall power of the ambient material lighting on the map. Default is 8.
- ScaleFX: Functionality not available in the current version of the content editor.
- SAO Intensity Power: Controls the intensity of shadows. Default is set to 1.
- SAO Sample Radius: Controls how far light it spreads away from objects, measured in meters. Default is 4.
- SAO Gain: Moves the start point of the amount of "black" in shadows. Default is 3.5.
- SAO Spec Blend: Allows you to control the terrain light blending. Default is set to 0.8.
It is recommended you start with the default values mentioned above and shown below. When adjusting these settings to suit the needs of your scene, it is a good idea to have both large structures and units visible in the scene.
Sky
AtmScattering, short for "Atmospheric Scattering," is your map's sky, which includes clouds and the light emitted by your map's skybox.
This controls one of your biggest lights in the editor (the sky) and the atmosphere values, which most often span from cool blue to warm yellow/orange. These values can greatly affect the look of your map.
When making changes to the Atmospheric Scattering, it is recommended you adjust these values while looking at your terrain and ideally some water as well, as these two materials reflect your sky the most.
- ScatteringTurbidity: Controls the atmosphere transparency, or "haziness," of the air. Higher values add dust to the atmosphere letting less light through. Default is set at 1.
- ScatteringAbsorption: Controls the amount of light blocked by air. Overcast skies have higher absorption values and will darken the sky.
- ScatteringPhaseParam: Controls the "glow" around the sun. Larger values heighten the glow.
- ScatteringStrength: Adjusts the strength of the light scattering effect. Low values (1-4) are dark and high values (6-15) are bright. Default is 5.
- ScatteringMieConstant: Red scattering values. Lower values (below 200) produce a cool colour to the sun's glow, while higher values (above 2000) produce warmer colours.
- ScatteringRayleighConstant: Blue scattering values. Lower values (below 200) produce a darker more blue sky, while higher values produce a brighter more yellow sky.
- ScatteringGroundLevel: Determines what height the scattering effect begins. Default is set at 0.
- ScatteringTopHeight: Determines the maximum height of the scattering effect. Lower values results in a darker, bluer sky, and greater values results in a brighter, warmer sky.
Wind
Wind settings control how the direction and strength of the wind effect on your map.
This effect is seen when the wind interacts with grass, still water, trees, flags, and similar elements.
- Direction: The direction the wind blows in relation to the player camera measured in degrees. For the standard camera, the default should be up around 90 degrees.
- Direction Water: The direction of the ripples that the wind creates across the surface of water.
- Declination: Controls the angle the wind blows at. The default is set to 0.
- Strength: Controls the strength of the wind.
- Influence Strength: Controls the degree to which the wind affects grass and trees.
- Strength Water: Controls the degree to which wind affects water. Note that this only affects water that has no flow, as flow overrides the effect of wind.
Blending Wind Speeds
Note that blending different wind speeds (either in influence or between 2 atmospheres) creates a number of problems with the grass calculations.
For the best results, it is recommended the strength be set to 1 for most scenarios.
Fog
Volumetric Fog Scattering controls the fog effects on your map, which can create effects anywhere between light mist to heavy low-hanging clouds.
These effects can have a dramatic impact on the look of your map.
Fog uses two unique terms: Height and Falloff.
The Height of fog refers to height at which the fog gets no denser, past which it starts to thin out.
The Falloff is how quickly the fog thins out after passing the height threshold.
- Fog Density: Controls the opacity of the fog.
- Fog Height Offset: Controls the level of fog in low-lying areas.
- Fog Height Falloff: Controls the sharpness of the edge of the low-lying fog. Value of 1 results in sharper edges, closer to 0 results in softer edges.
- Fog Wall Offset: Provides control over distance to solid 100% fog.
- Fog Wall Falloff: Controls the sharpness of the edge of fog falloff distance. Value of 1 results in sharper edges, closer to 0 results in softer edges.
- Fog Scattering Direction: Allows fog to absorb light becoming dark, and glow when facing light. I usually leave this to 0 and Absorption Factor (a multiplier of this effect) to 0.
Fog and FX
Keep in mind that fog renders on top of any special effects and will gradually erase all FX the thicker the fog gets.
Make sure to test any special effects on your map before settling on a final fog density.
Clouds
Clouds can cast shadows on both the ground and water as well affect how much light reaches the ground.
The LayerCloud modify how the clouds look and behave on your map.
Base Shape Map and Erosion Map combine to create cloud volume (should not be edited) wherever a cloud 'might' be, based on the coverage map and settings levels.
- Base Shape Map Name: Controls the "billowy" shape of clouds.
- Erosion Map Name: Controls the effect used to "eat away" at the cloud edges to give a sense of turbulence.
- Coverage Map Name: Controls the main shape and distributions of the clouds. While this can be edited, the default image is recommended for most purposes.
- Detail Mask Name: The texture that that masks out (subtracts from) the above Coverage Map Name. Set to 0 to disable this effect.
- Scale: Increases or decreases the size of the clouds.
- Detail Mask Scale: Scales the size of the clouds. Smaller clouds will have more gaps between them and block less light.
- Coverage: Controls how much cloud cover is present on the map. is cloud cover. A value of 0 results in a clear sky, while a value of 3 is overcast.
- Erosion Intensity: Increases or decreases the influence of the Erosion Map in the overall cloud volume.
- Scroll Direction: Changes the direction the clouds appear to drift in.
- Coverage Scroll Speed: Adjusts the speed of the clouds as they drift across the map.
- Noise Scroll Speed: Controls the speed at which the noise textures slide past the main clouds to give the clouds detail. This detail is most noticeable on the edges of clouds and does not affect the large scale drift of your cloud cover.
- Base Shape Contrast Factor: Controls the intensity of the of the base cloud shape texture. Settings above 0 can produce erratic behavior, although some interesting results can be achieved.
- Ambient Desaturate: Adjusts the level of tint the coloured terrain bounces up onto the clouds, and subsequently back down to the terrain.
- Density Scale: Sets the scale of how dense the clouds are. Denser clouds mean the map becomes darker as more light is scattered.
- Thickness: Defines how thick in meters the clouds radius is based on the value in the Coverage Mask.
- Back Scattering: Defines the back scattering for the clouds. This is heavily affected by sun direction.
- Front Scattering: Defines the front scattering for the clouds, depending on the sun's direction.
- Scattering Blend: Defines the blend effect between the two lobes.
Colour Grading
Colour Grading will "tint" the map as a whole, allowing you to achieve a variety of specific stylistic effects.
This colour grading effect is divided into three distinct zones:
- "Influenced Areas," or areas within the territory of a town or city
- Unexplored areas within the Fog of War (FoW)
- Areas that Transition between these two areas
Transitions, Camera Movement, and Influence Ranges all affect how Age of Empires IV determines an Influenced Area, and how it then blends from normal to influenced and back.
These parameters are used to prevent mouse clicking on the minimap to an area and seeing the "transition" happen over a long period of time, and to soften the blend as the player pans around towards, within, or away from an Influenced Area.
The most important settings for tone are the Highlight, Midtone, and Shadow.
These controls are divided into two main categories, affecting the colour of both the Influenced Area and the Fog of War (FOW).
- Tint affects the tint of the wilderness areas of a map
- Tint1 affects the area between Influenced Areas and the wilderness
- Tint2 affects the tint within Influenced Areas
Saturation
In addition to affecting highlights, mid-tones, and shadows, Colour Grading also affects saturation.
A saturation level of 127 is the mid level where no saturation changes happen. A saturation of 0 would produce greyscale and 255 would be horrifically colour saturated.
The examples below show the effects of this saturation.
No tint and 0% saturation.
No tint and 50% saturation.
No tint and 100% saturation.
Influence Settings
Influence settings control the parameters of any "Influenced" versions of their default counterparts above.
These settings are only visible within the game or in editor if the camera is currently looking at a city.
Influenced variable include only a small subset we (at the time) deemed useful. They include:
- Shadow Penumbra: Functionality not available in the current version of the content editor.
- Cloud: Allows you to adjust cloud settings within influenced areas.
- Sky: Allows you to adjust sky settings within Influenced Areas
- Fog: Allows you to adjust fog settings within Influenced Areas.
The copy values button (☐) copies values from the settings in other regions to use as a starting place for tuning the tint of a specific area.
Fog of War
The FogOfWar(FOW) settings allow you to change the colour of both the Fog of War and the Shroud.
- Shroud is a completely unexplored area that appears dark and opaque.
- Fog of War is an explored area that your units currently do not have sight in.
While the Shroud and Fog of War are locked as opaque, you can change their colour, often producing remarkable ways.
Example of Shroud and Fog of War tinted purple.
Debug Overrides
Debug Overrides help visualize various features and do not save with the atmosphere file, and only affect the current view in editor.
Tick the Influence Override to enable the slider (0-1)
tick Enable Emulated FOW to see the FOW/SOW settings you're working on in FogOfWar.
Testing Atmosphere in Game
To test what your atmosphere settings look like in game, you can quickly and easily test them using the following workflow:
- Run the game with your saved map.
- Press Ctrl + Enter to get the cheat menu.
- Use the arrow keys to get to the bottom of the list where you'll find Atmosphere.
- You can set a temporary transition time (in seconds) between this and the next chosen atmosphere.
- You can choose previous or next if you like
- Or you can specifically choose any named atmosphere you added to your map