add recursive subsystem rendering

docs/src/examples/pendulum.md

@@ -71,6 +71,7 @@ Multibody.jl supports automatic 3D rendering of mechanisms, we use this feature
 ```@example spring_mass_system
 import WGLMakie
 Multibody.render(model, sol; z = -5, filename = "pendulum.gif") # Use "pendulum.mp4" for a video file
+nothing # hide
 ```
 
 ![animation](spherical.gif)

docs/src/examples/spherical_pendulum.md

@@ -40,6 +40,7 @@ Multibody.jl supports automatic 3D rendering of mechanisms, we use this feature
 ```@example spring_mass_system
 import WGLMakie
 Multibody.render(model, sol; z = -5, filename = "spherical.gif") # Use "spherical.mp4" for a video file
+nothing # hide
 ```
 
 ![animation](spherical.gif)

docs/src/examples/spring_damper_system.md

@@ -82,6 +82,7 @@ Multibody.jl supports automatic 3D rendering of mechanisms, we use this feature
 ```@example spring_mass_system
 import WGLMakie
 Multibody.render(model, sol; z = -5, filename = "springdamper.gif") # Use "springdamper.mp4" for a video file
+nothing # hide
 ```
 
 ![animation](springdamper.gif)

docs/src/examples/spring_mass_system.md

@@ -64,6 +64,7 @@ Multibody.jl supports automatic 3D rendering of mechanisms, we use this feature
 ```@example spring_mass_system
 import WGLMakie
 Multibody.render(model, sol; z = -5, filename = "springmass.gif") # Use "springmass.mp4" for a video file
+nothing # hide
 ```
 
 ![animation](springmass.gif)

docs/src/examples/three_springs.md

@@ -51,6 +51,7 @@ Multibody.jl supports automatic 3D rendering of mechanisms, we use this feature
 ```@example spring_mass_system
 import WGLMakie
 Multibody.render(model, sol; z = -5, filename = "three_springs.gif") # Use "three_springs.mp4" for a video file
+nothing # hide
 ```
 
 ![animation](three_springs.gif)

ext/Render.jl

@@ -64,10 +64,7 @@ function render(model, sol,
  t = 0.0
  t = Observable(timevec[1])
 
- for subsys in model.systems
- system_type = get_systemtype(subsys)
- render!(scene, system_type, subsys, sol, t)
- end
+ recursive_render!(scene, model, sol, t)
 
  record(scene, filename, timevec; framerate) do time
  t[] = time
@@ -95,16 +92,28 @@ function render(model, sol, time::Real;
  ]
  # t = Observable(time)
 
+ recursive_render!(scene, model, sol, t)
+ fig, t
+end
+
+"""
+Internal function: Recursively render all subsystem components of a multibody system. If a particular component returns `true` from its `render!` method, indicating that the component performaed rendering, the recursion stops.
+"""
+function recursive_render!(scene, model, sol, t)
  for subsys in model.systems
  system_type = get_systemtype(subsys)
- render!(scene, system_type, subsys, sol, t)
+ did_render = render!(scene, system_type, subsys, sol, t)
+ if !did_render
+ recursive_render!(scene, subsys, sol, t)
+ end
  end
- fig, t
 end
 
+render!(scene, ::Any, args...) = false # Fallback for systems that have no rendering
+
 
 """
- render!(scene, ::typeof(ComponentConstructor), sys, sol, t)
+ did_render::Bool = render!(scene, ::typeof(ComponentConstructor), sys, sol, t)
 
 Each component that can be rendered must have a `render!` method. This method is called by `render` for each component in the system.
 
@@ -117,6 +126,9 @@ thing = @lift begin
 end
 mesh!(scene, thing; style...)
 ```
+
+# Returns
+A boolean indicating whether or not the component performed any rendering. Typically, all custom methods of this function should return `true`, while the default fallback method is the only one returning false.
 """
 function render!(scene, ::typeof(Body), sys, sol, t)
  thing = @lift begin # Sphere
@@ -150,6 +162,7 @@ function render!(scene, ::typeof(Body), sys, sol, t)
  # Makie.GeometryBasics.Cylinder(origin, extremity, radius)
  # end
  # mesh!(scene, thing, color=:purple)
+ true
 end
 
 function render!(scene, ::typeof(World), sys, sol, t)
@@ -174,6 +187,7 @@ function render!(scene, ::typeof(World), sys, sol, t)
  Makie.GeometryBasics.Cylinder(O, z, radius)
  end
  mesh!(scene, thing, color=:blue)
+ true
 end
 
 function render!(scene, ::typeof(Revolute), sys, sol, t)
@@ -185,6 +199,7 @@ function render!(scene, ::typeof(Revolute), sys, sol, t)
  Sphere(point, 0.1)
  end
  mesh!(scene, thing, color=:red)
+ true
 end
 
 function render!(scene, ::typeof(Spherical), sys, sol, t)
@@ -195,9 +210,10 @@ function render!(scene, ::typeof(Spherical), sys, sol, t)
  Sphere(point, 0.1)
  end
  mesh!(scene, thing, color=:yellow)
+ true
 end
 
-render!(scene, ::typeof(FreeMotion), sys, sol, t) = ()
+render!(scene, ::typeof(FreeMotion), sys, sol, t) = true
 
 
 function render!(scene, ::typeof(FixedTranslation), sys, sol, t)
@@ -210,6 +226,7 @@ function render!(scene, ::typeof(FixedTranslation), sys, sol, t)
  Makie.GeometryBasics.Cylinder(origin, extremity, radius)
  end
  mesh!(scene, thing, color=:purple)
+ true
 end
 
 function render!(scene, ::typeof(BodyShape), sys, sol, t)
@@ -231,6 +248,7 @@ function render!(scene, ::typeof(BodyShape), sys, sol, t)
  # Makie.GeometryBasics.Sphere((r1+r2) ./ 2, 0.1f0)
  # end
  # mesh!(scene, thing, color=:purple)
+ true
 end
 
 
@@ -245,6 +263,7 @@ function render!(scene, ::typeof(Damper), sys, sol, t)
  Makie.GeometryBasics.Cylinder(origin, extremity, radius)
  end
  mesh!(scene, thing, color=:gray)
+ true
 end
 
 
@@ -255,12 +274,10 @@ function render!(scene, ::typeof(Spring), sys, sol, t)
  spring_mesh(r1,r2)
  end
  plot!(scene, thing, color=:blue)
+ true
 end
 
 
-
-render!(scene, ::Any, args...) = () # Fallback for systems that have no rendering
-
 function render!(scene, ::Function, sys, sol, t, args...) # Fallback for systems that have at least two frames
  count(ModelingToolkit.isframe, sys.systems) == 2 || return
  try
@@ -275,6 +292,7 @@ function render!(scene, ::Function, sys, sol, t, args...) # Fallback for systems
  mesh!(scene, thing, color=:green, alpha=0.5)
  catch
  end
+ true
 end
 
 function spring_mesh(p1, p2; n_wind=6, radius=0.1f0, N=200)