From e2f044ee8e09f162ac19158db0843f8be307c8bc Mon Sep 17 00:00:00 2001
From: Twan Koolen <koolen.twan@gmail.com>
Date: Mon, 10 Dec 2018 13:04:10 -0500
Subject: [PATCH] Add Cone primitive.

---
 src/MeshCat.jl     |  1 +
 src/geometry.jl    | 17 ++++++++++++++++-
 src/lowering.jl    | 12 ++++++++++++
 test/visualizer.jl |  7 +++++++
 4 files changed, 36 insertions(+), 1 deletion(-)

diff --git a/src/MeshCat.jl b/src/MeshCat.jl
index 98b4270..03affc6 100644
--- a/src/MeshCat.jl
+++ b/src/MeshCat.jl
@@ -43,6 +43,7 @@ export Object,
        HyperEllipsoid,
        HyperCylinder,
        PointCloud,
+       Cone,
        Triad,
        Mesh,
        Points,
diff --git a/src/geometry.jl b/src/geometry.jl
index e142073..11cf37a 100644
--- a/src/geometry.jl
+++ b/src/geometry.jl
@@ -6,7 +6,6 @@ end
 
 GeometryTypes.origin(geometry::HyperEllipsoid{N, T}) where {N, T} = geometry.center
 radii(geometry::HyperEllipsoid{N, T}) where {N, T} = geometry.radii
-center(geometry::HyperEllipsoid) = origin(geometry)
 
 @deprecate HyperCylinder(length::T, radius) where {T} Cylinder{3, T}(Point(0., 0., 0.), Point(0, 0, length), radius)
 
@@ -26,10 +25,20 @@ struct Triad <: AbstractGeometry{3, Float64}
     Triad(scale=20.0) = new(scale)
 end
 
+struct Cone{N, T} <: AbstractGeometry{N, T}
+    origin::Point{N, T}
+    apex::Point{N, T}
+    r::T
+end
+
+GeometryTypes.origin(geometry::Cone) = geometry.origin
+
+center(geometry::HyperEllipsoid) = origin(geometry)
 center(geometry::HyperRectangle) = minimum(geometry) + 0.5 * widths(geometry)
 center(geometry::HyperCube) = minimum(geometry) + 0.5 * widths(geometry)
 center(geometry::HyperSphere) = origin(geometry)
 center(geometry::Cylinder) = origin(geometry) + geometry.extremity / 2
+center(geometry::Cone) = (origin(geometry) + geometry.apex) / 2
 
 """
 $(SIGNATURES)
@@ -51,3 +60,9 @@ function intrinsic_transform(g::Cylinder{3})
     R = rotation_between(SVector(0, 1, 0), g.extremity)
     Translation(center(g)) ∘ LinearMap(R)
 end
+
+function intrinsic_transform(g::Cone{3})
+    # Three.js wants a cone to lie along the y axis
+    R = rotation_between(SVector(0, 1, 0), g.apex - g.origin)
+    Translation(center(g)) ∘ LinearMap(R)
+end
diff --git a/src/lowering.jl b/src/lowering.jl
index c4cedfc..18dfb50 100644
--- a/src/lowering.jl
+++ b/src/lowering.jl
@@ -96,6 +96,18 @@ function lower(g::HyperEllipsoid{3})
     )
 end
 
+function lower(g::Cone{3})
+    # Radius and height are always 1 because we handle these
+    # in intrinsic_transform
+    Dict{String, Any}(
+        "uuid" => string(uuid1()),
+        "type" => "ConeGeometry",
+        "radius" => g.r,
+        "height" => norm(g.apex - g.origin),
+        "radialSegments" => 100,
+    )
+end
+
 function lower(t::Triad)
     attributes = Dict{String, Any}(
         "position" => lower([Point3f0(0, 0, 0), Point3f0(t.scale, 0, 0),
diff --git a/test/visualizer.jl b/test/visualizer.jl
index 947696f..5a651f7 100644
--- a/test/visualizer.jl
+++ b/test/visualizer.jl
@@ -82,6 +82,13 @@ end
             setobject!(v[:triad], Triad(0.2))
             settransform!(v[:triad], Translation(0, 3, 0.2))
         end
+
+        @testset "cone" begin
+            setobject!(v[:cone],
+                Cone(Point(1., 1., 1.), Point(1., 1., 1.2), 0.1),
+                MeshLambertMaterial(color=colorant"indianred"))
+            settransform!(v[:cone], Translation(-1, 2.5, -1))
+        end
     end
 
     @testset "meshes" begin