Using Generators
Table of contents
Introduction
Generators are used to generate items, humans and vehicles. These are useful to use rather than having to place down multiples of elements to create a scenario.
Features
(Fig.1) Assets Helpers
- Asset Menu
- Helper menu - generator
(Fig.2) Generators
- Details
- Max speed - The maximum speed of a vehicle
- Settings
- Sphere shape - circle rather than a square
- Generator width
- Generator length
- Random position - randomises where items are generated from
- Position offset - sets where items will be generated
- Random orientation - the direction items go in is randomised
- Orientation offset
- Picklist/Actor configuration - Shows a dropdown of all the picklists and digital humans in your scenario
- Circuits - All circuits in your scenario will be shown here. A generator can use multiple circuits
- Generation rate - seconds between items being generated
- Poisson - randomly distributes generation but with a mean average based on generation rate
- Mean - The arithmetic mean speed of generated objects
- Sigma - The standard deviation of the speed function
- Time to live - how long an item exists in the scene
Explanation
Concept
A generator, like all the helper elements, are best thought of as hit boxes. What do we mean by a hit box, it means, in the case of a generator that while an element exists within the generator area, nothing else will be generated until the last generated element has left the box. This has implications for some of the setting that you have available to you, which will be pointed out in the rest of this guide.
Max Speed
This function only applies to vehicles. The figure used is multiplied by the normalised random gaussian. The value produced by mean and sigma by the maximum desired speed of the vehicle.
Generation area
As default items will always be generated in the centre of the generator area.
Generator size
As said in the concept section, the size of the hit box will effect the way the generator performs.
Random position
Checking this will randomise where items are generated within the area.
Position offset
Using these settings allows you to customise where items are generated. The offset works from within the centre of the generator.
Generated Items
Picklist/Digital human
The only way to get the generator to produce items is to either create a picklist or create a digital human. You can find out how to create picklist here and digital humans here
Random orientation
The generator has a default direction shown by the arrow on the generator. Checking this means that items will be given a random direction.
Orientation offset
Adjust the default direction of the generator.
Circuits
A generator can use any circuit in the scenario. If the generator is not near the circuit, items will usually go to the nearest one and use that circuit before moving on to the next circuit. When using actors they will run to the first point of the circuit, before using the circuit. You can learn more about circuits here
Generation rate
The generation rate is measured in frames. a generator will only generate a new item once the previous item has left the generator area.
Poisson
Poisson randomises the generation of items in a more evenly distributed manner. You can see an example of this below.
Time to live
Time an item generated last in the scene in frames. If it is set to zero the item will live throughout the scenario.
Guide
- Go to the Assets menu (Fig.1-1), open the helpers dropdown and select MT_Generator (Fig.1-2)
- Once selected, place the generator in the desired location. You will notice there is an arrow on the generator. This is the default direction any element that moves, will move in.
- Now you need to add a pick list or a digital human.
- If an item moves eg vehicle or human, we recommend using a circuit or an attractor to move them away from the generator so more items can be created. If the objects are stationary then use the time to live option to regenerate a new object after so many frames.