Glow maps (glowMaps) allow you to switch between multiple materials based on a number value.

The most common use case of glow maps is vehicle lights, hence the name. This includes headlights, taillights, gauge lights, etc. In those cases they are used for changing the light materials to emissive variants of themselves. Check this page for more information about light materials. However, they can be used for any kind of application that involves changing a material on the fly.

Syntax

Unlike most other Jbeam sections, the glowMap section is not a table but rather a dictionary. The key is the name of the associated material as set in the modelling softwate, while the value is another dictionary. It can contain multiple different dictionaries inside of it which will be described later, along with 3 values referred to as “material slots”, under the keys “off”, “on” and “on_intense”. Their values are different materials the part will be using based on the resulting value of simpleFunction or advancedFunction.

"glowMap":{
  "taillights":{
    "simpleFunction":{"lowhighbeam":0.49,"brake":0.49}, "off":"lights", "on":"lights_on", "on_intense":"lights_on_intense"
  },
}

While glowMaps support applying a material with the same name as their own key, it is recommended to avoid this, to prevent possible unwanted behaviour due to changes within the game. The material defined as the glowMap key does not need to be added to the vehicle’s materials.json files as it is generated automatically for each vehicle - however, for materials present in the “common” folder it is still necessary as they are not assigned to a single vehicle but shared between all of them. For this purpose, dummy materials are used.

Available material slots

Each glow map offers the possibility for 3 different switchable materials, refered to as “off”, “on” and “on_intense”. The switch between modes works by adding together a few inputs using multipliers. If the total value is less than 0.0001, the glowMap will be “off”, between 0.0001 and 0.5 will be “on”, and above will be “on_intense”. The function result can be greater than 1.

Glowmap Value Calculation

A typical vehicle glowMap section looks like this:

"glowMap":{
  //exterior lights
  "signal_L": {"simpleFunction":{"signal_L":0.49},             "off":"light","on":"light_on","on_intense":"light_on_intense"},
  "signal_R": {"simpleFunction":{"signal_R":0.49},             "off":"light","on":"light_on","on_intense":"light_on_intense"},
  "taillight":{"simpleFunction":{"lowhighbeam":0.49,"brake":1},"off":"light","on":"light_on","on_intense":"light_on_intense"},
  "chmsl":    {"simpleFunction":{"brake":100},                 "off":"light","on":"light_on","on_intense":"light_on_intense"},
  "foglight": {"simpleFunction":{"fog":1},                     "off":"light","on":"light_on","on_intense":"light_on_intense"},
  "headlight":{"simpleFunction":{"lowbeam":0.49,"highbeam":1}, "off":"light","on":"light_on","on_intense":"light_on_intense"},
  "reverse":  {"simpleFunction":{"reverse":0.49},              "off":"light","on":"light_on","on_intense":"light_on_intense"},
  //gauge faces and needles
  "gauges": {"simpleFunction":{"lowhighbeam":0.6}, "off":"gauges","on":"gauges_on"},
  //gauge lights
  "signal_L":    {"simpleFunction":"signal_L",     "off":"invis", "on":"decals_gauges"},
  "signal_R":    {"simpleFunction":"signal_R",     "off":"invis", "on":"decals_gauges"},
  "checkengine": {"simpleFunction":"checkengine",  "off":"invis", "on":"decals_gauges"},
  "hazard":      {"simpleFunction":"hazard",       "off":"invis", "on":"decals_gauges"},
  "battery":     {"simpleFunction":"battery",      "off":"invis", "on":"decals_gauges"},
  "highbeam":    {"simpleFunction":"highbeam",     "off":"invis", "on":"decals_gauges"},
  "parkingbrake":{"simpleFunction":"parkingbrake", "off":"invis", "on":"decals_gauges"},
  "lowfuel":     {"simpleFunction":"lowfuel",      "off":"invis", "on":"decals_gauges"},
  "abs":         {"simpleFunction":"abs",          "off":"invis", "on":"decals_gauges"},
}

The entire glowMap functionality depends on Vehicle Lua electrics values. See here for a list of available defaults. It should be noted that while most of the values will always be 0 or 1, some of them can return inbetween numbers. For example “brake” is equal to the braking input, meaning the value can be anywhere between 0 and 1. Keep this in mind when definining the weight of the various functions to make sure they work as expected.

The value can be calculated in 3 different ways based on those values:

• Directly taken from a single electrics value, via the binary variant of simpleFunction
• Summed up from multiple electrics values with multipliers, via the complex variant of simpleFunction
• Calculated from a Lua code snipped, provided inside advancedFunction

Binary simpleFunction

If the “simpleFunction” argument is provided and is a string, it is expected to be the name of an electrics value. This sets the glowmap value to exactly this electrics value without any modifications or calculations. For example, this glowMap will use the “off” material when the brake is not in use. As soon as the brake is enabled, the “on” state is used.

"glowMap":{
  "brakelights":{"simpleFunction":"brake", "off":"lights", "on":"lights_on"},
}

Complex simpleFunction

The “simpleFunction” argument may also be a dictionary containing the names of electrics values, each assigned to a multiplier they add to the glowmap value. Negative modifiers are supported and the total result can be greater than 1. This is the most common method of calculating the glowmap value. For example, this glowmap will use the “off” material when the lights are off and the brake is not in use. As soon as either are enabled, the “on” state is used. When both are enabled, the “on_intense” state is used. If this state is not defined, the “on” state will replace it.

"glowMap":{
  "taillights":{
    "simpleFunction":{"lowhighbeam":0.49,"brake":0.49}, "off":"lights", "on":"lights_on", "on_intense":"lights_on_intense"
  },
}

It should be noted in that specific case that while lowhighbeam will always be 0 or 1, brake is equal to the braking input, meaning the value can be anywhere between 0 and 1.

Advanced Example

This simpleFunction creates a combined DRL/signal glowmap value.

When the engine is enabled, “running” is set to true. This adds 0.49 to the glowmap and switches the state to “on”.
When the right signal is activated, “signal_right_input” is set to true and 1 is subtracted from the glowmap value, making it use the “off” material despite “running” being true.
“signal_R” is activated and deactivated based on a timer to achieve a blink effect. When it is active, it adds 2 to the glowMap value, resulting in a value higher than 0.5.

"glowMap":{
  "running_signal_R":{
    "simpleFunction": {
      "signal_right_input": -1,
      "running": 0.49,
      "signal_R": 2
    },
    "off":"lights", "on":"lights_on", "on_intense":"lights_on_intense"
  },
}

advancedFunction

advancedFunction supports using a straight Lua code snippet to calculate its value. This gives you direct control over the glowmap without requiring an external Lua module. This feature is not often used, the simplest use case is for a gear display. This method requires a dictionary with the following keys:

"triggers":["gear"],

"triggers":{"1":"gear","2":"gearIndex"},

"triggers":{"":"gear"},

For example, this advancedFunction switches to “on” when the park gear is selected.

"glowMap":{
  "citybus_transmission_DSP_P": {
    "advancedFunction":{
      "triggers":{"":"gear"}, "cmd":"gear=='P' and 1 or 0"
    },
    "off":"invis""on":"citybus_transmission_DSP"
  },
}

And this one switches to “on” when the transmission is in 2nd gear.

"glowMap":{
  "citybus_transmission_DSP_2": {
    "advancedFunction":{
      "triggers":{"":"gearIndex"}, "cmd":"gearIndex==2 and 1 or 0"
    },
    "off":"invis", "on":"citybus_transmission_DSP",
  },
}

Advanced Example

This advancedFunction emulates the behaviour of the combined DRL/signal simpleFunction showcased in the advanced example above.

"glowMap":{
  "running_signal_R":{
    "advancedFunction":{
      "triggers": {
        "1": "signal_right_input",
        "2": "engineRunning",
        "3": "signal_R"
      },
      "cmd": "engineRunning*0.49 + signal_R*2 - signal_right_input"
    }
  }
}

Material transitions

For the purpose of realistic halogen and sealed beam lights, it is possible to define transitions between the states of the lights.

This works by modifying the emissiveFactor of the glowing light materials via a smoother . In the glowMap section, this is achieved by using special electrics values defined in the electrics section, and specifying its treshold value where the emissiveFactor of the “on” material is at its maximum value, which is done in the “materialEmissiveScaling” argument.

"glowMap":{
  "sealedbeam_auxlight": {
    "simpleFunction":{
      "foglight_filament":0.49
    }, 
    "off":"sealedbeam", "on":"sealedbeam_on", "materialEmissiveScaling":{"on_max":0.49}
  },
  "sealedbeam_auxlightglass": {
    "simpleFunction":{
      "foglight_filament":0.49
    }, 
    "off":"sealedbeam_glass", "on":"sealedbeam_glass_on", "materialEmissiveScaling":{"on_max":0.49}
  },
}

Multiple input values are also possible the same way as they are used with standard electrics functions. Thanks to the dynamic emissiveFactor of the material, the “on_intense” state of the lights is not needed here - “on” will be used as the maximum value, and the middle state will be the transition between “off” and “on”.

"glowMap":{
  "sealedbeam_headlight": {
    "simpleFunction":{
      "lowbeam_filament":0.49,"highbeam_filament":1
    }, 
    "off":"sealedbeam", "on":"sealedbeam_on_intense", "materialEmissiveScaling":{"on_max":1}
  },
  "sealedbeam_headlightglass": {
    "simpleFunction":{
      "lowbeam_filament":0.49,"highbeam_filament":1
    }, 
    "off":"sealedbeam_glass", "on":"sealedbeam_glass_on_intense", "materialEmissiveScaling":{"on_max":1}
  },
}