Provides visualization tools for AutomotiveDrivingModels. Built on Cairo
Author sisl
26 Stars
Updated Last
2 Years Ago
Started In
August 2016


Build Status Coverage Status

A package for rendering simple scenes primarily consisting of cars on roadways using Cairo.

AutoViz is undergoing significant changes. If you are looking for the version before these changes that is designed around AutomotiveDrivingModels.jl, please checkout the v0.6.0 tag.



In julia 1.1+, the preferred way is to add the SISL registry and install AutoViz as follows:

] registry add
] add AutoViz


**Warning: This part of the documentation is not up to date, the documentation website will be updated soon, the notebook tutorial is up to date with AutoViz v0.8 **

AutoViz works by adding rendering instructions to a RenderModel, and finally applying those instructions to a canvas using the render function.

Basic Usage

In the simplest case, a roadway and a scene of types Roadway and Scene respectively can be rendered via

render([roadway, scene])

However, the rendering interface is much more flexible than that, supporting custom rendering and cameras.

Renderable Objects

In order for an object of type ObjectType to be "renderable", we need to provide a function with the signature

    add_renderable!(rendermodel::RenderModel, obj::ObjectType)

The basic example above works, because AutoViz implements the add_renderable! function for commonly used types such as Roadway, Entity or Scene. In general, the render(renderables) function can take any collection of renderable objects. AutoViz provides a series of convenient wrapper objects such as FancyCar, FancyPedestrian, EntityRectangle to make entities renderable.


A Camera object specifies what portion of the scene should be rendered.

By default, render(renderables) uses a static camera. In order to use an adaptive camera, the camera object needs to be updated before rendering and passed in to the render function as a keyword argument.

update_camera!(scene, camera)
render([roadway, scene], camera=camera)

Full Example

# define roadway and vewhicle objects
roadway = gen_straight_roadway(3, 100.0)
lane = roadway[LaneTag(1,2)]
def = VehicleDef(length=5., width=2.)
ego = Entity(VehicleState(Frenet(lane, 50.,  0., 0.), roadway, 5rand()), def, :ego)
carA = Entity(VehicleState(Frenet(lane, 20.,  2., -.2), roadway, 5rand()), def, :carA)
carB = Entity(VehicleState(Frenet(lane, 40.,  -2., -.1), roadway, 5rand()), def, :carB)
carC = Entity(VehicleState(Frenet(lane, 60.,  0., .4), roadway, 5rand()), def, :carC)
carD = Entity(VehicleState(Frenet(lane, 80.,  3., .1), roadway, 5rand()), def, :carD)
scene = Scene([ego, carA, carB, carC, carD])

# define camera and adjust to scene
camera = TargetFollowCamera(:ego; y=0., zoom=12.)
update_camera!(camera, scene)

# render
renderables = [
    FancyCar(car=ego, color=colorant"blue"),
    FancyCar(car=carA, color=rand(RGB)),
    FancyCar(car=carB, color=rand(RGB)),
    EntityRectangle(entity=carC, color=rand(RGB)),
    EntityRectangle(entity=carD, color=rand(RGB)),
    TextOverlay(text=["AutoViz rocks!"], font_size=60, pos=VecE2(400, 100), color=colorant"green")
for veh in scene
    push!(renderables, VelocityArrow(entity=veh))
img = render(renderables, camera=camera)

In a jupyter notebook, an image will appear, otherwise see the Saving images section below. A short tutorial is located in notebooks/tutorial.ipynb.

Roadways and ArrowCars

The primary basic directly renderable types are Roadway (now from AutomotiveDrivingModels; soon from Roadways.jl) and ArrowCar.

ArrowCars are the pink cars with arrows that are in everyone's videos. You can construct one like this:

using Colors
using AutoViz

# x, y, angle and velocity are from your simulation

ArrowCar(x, y, angle; color=colorant"green", text="v: $velocity")

How to make types renderable

There are two ways to make renderable types.

  1. You can make your existing types renderable by conversion by defining convert(::Type{Renderable}, ::MyType) which should return a directly renderable object, e.g. an ArrowCar.
  2. You can make types directly renderable by defining render!(::RenderModel, ::MyType). To make things easier for the compiler, you can also define isrenderable(::Type{MyType}) = true. If you want to allow others to convert to this type to make their types renderable by conversion, make your type a subtype of Renderable.


Overlays will function as in the previous version of AutoViz. They will be rendered last with render!(rendermodel, overlay, scene).

Additional keyword arguments for render()

The following additional keyword arguments will accepted by render():

  • canvas_width
  • canvas_height
  • rendermodel
  • overlays
  • cam - a camera controlling the field of view as in the previous version of AutoViz

Saving images

Png images can be saved with write_to_png(render(scene), "filename.png") or write_to_svg(render(scene), "filename.svg"). Gif animations may be created with e.g. Reel.jl.


The mid-level interface for this package (which is what you will use when you write render!() for your types or when you write an overlay) revolves around adding instructions to a RenderModel. Each instruction consists of a function and a tuple of arguments for the function. This is not documented in this readme, but it is fairly easy to figure out by reading rendermodels.jl, overlays.jl, and arrowcar.jl.


AutoViz.jl has two display mode: a "fancy" mode (default) that uses the svg representations in icons/ to display cars and pedestrian, and a more basic mode where cars are rendered as rounded rectangles. To turn-off the fancy mode you can run:

AutoViz.set_render_mode(:basic) # set to :fancy for fancy mode

In addition you can also change the color theme. Three color themes are provided: MONOKAY (default), OFFICETHEME, LIGHTTHEME. You can change the color theme by running:

using AutoViz

You can also define your own color theme using a dictionary. Look at the example in src/colorscheme.jl to have the correct key names.

Change Log



  • Clean-up of the rendering interface: there is now only one single rendering function with the signature
render!(rendermodel::RenderModel, renderables::AbstractVector; canvas_width::Int, canvas_height::Int, surface::CairoSurface))

All keyword arguments are optional. Objects of type Renderable now no longer have to implement the render! function (which is a misleading name). Instead one must implement the add_renderable! function which adds the rendering instructions to the RenderModel.

  • Implicit conversions of non-renderable objects (such as obj::Scene{Entity{S,D,I}}) via implementations of Base.convert(Renderable, obj) are now discouraged. Instead, one can overwrite the add_renderable! method for such types. This is done for some very common types.
  • The new render! function now only takes objects which are renderable, i.e. which implement the add_renderable(rm::RenderModel, obj) function. There is no longer a distinction between drawing roadways, scenes or overlays. They all need to satisfy the same interface, and they are drawn in the order in which they are passed to the render! function. This change decreases the number of available render functions from almost ten to one and should make the control flow more clear.
  • Additional arguments to render! such as camera and car_colors are no longer supported. Camera effects should be applied before calling render! (see section below) and rendering attributes such as colors should be passed in as part of a renderable object.


  • Changed the interface for rendering overlays to only take an instance of RenderModel and the overlay itself. All additional data must be stored as part of the overlay if it is needed during rendering.
  • Added a RenderableOverlay wrapper which makes the legacy overlays work with the new rendering interface (in which overlays do not get any input arguments for rendering)


  • Changed the camera interface. The full state of the camera, such as camera_pos, camera_zoom, camera_rotation is stored in RenderModel (this has already been the case in previous AutoViz versions). A Camera acts upon a RenderModel by changing these internal variables. The function camera_set! now becomes update_camera!.
  • Many setter functions for the camera have been replaced by the set_camera!() function which takes keyword arguments for x, y and zoom.
  • The implementations of TargetFollowCamera (former CarFollowCamera) and SceneFollowCamera have been reviewed and simplified. Additionally, a ZoomingCamera type which gradually changes the zoom level has been introduced and for easy extensibility there is also a ComposedCamera type which takes a list of cameras and applies their effects sequentially to the RenderModel.
  • The new render! function no longer takes a camera as an input argument, but assumes that the camera settings have already been applied to the RenderModel via update_camera! prior to calling render!. User code should be adapted accordingly.

Visualization of Entities

  • Controlling the appearance of vehicles by setting set_render_mode(:basic|:fancy) is no longer encouraged. Instead, we provide new renderable types such as EntityRectangle, FancyCar, FancyPedestrian, VelocityArrow in addition to the already implemented ArrowCar type which can all be used to conveniently display entities.
  • A convenience function for rendering scenes directly (i.e. without explicit conversion to a Renderable type) is still supported.
  • TODO: make FancyCar work on my platform

1D Vehicles

  • Support for 1D vehicles has mostly been discontinued and some of the related functions were removed. However, the new functions should work seamlessly in many cases as long as the 1D vehicles implement basic functions such as posg, width, length from AutomotiveDrivingModels.jl