Add html pretty printing for ArcDiagrams (#169)

.gitignore

@@ -5,6 +5,7 @@ docs/build
 db
 
 # jupyter artifacts
+*.ipynb
 .ipynb_checkpoints
 
 # julia project Manifests

Project.toml

@@ -5,7 +5,9 @@ version = "0.4.0-DEV"
 
 [deps]
 Oscar = "f1435218-dba5-11e9-1e4d-f1a5fab5fc13"
+Preferences = "21216c6a-2e73-6563-6e65-726566657250"
 
 [compat]
 Oscar = "~1.0.3, ~1.1"
+Preferences = "1.4"
 julia = "1.8"

src/ArcDiagram.jl

@@ -40,6 +40,15 @@ function vertex_index(p::ArcDiagramVertex)
     return p[2]
 end
 
+function _vertex_lt(v1::ArcDiagramVertex, v2::ArcDiagramVertex)
+    if is_upper_vertex(v1) && is_lower_vertex(v2)
+        return true
+    elseif is_lower_vertex(v1) && is_upper_vertex(v2)
+        return false
+    else
+        return vertex_index(v1) < vertex_index(v2)
+    end
+end
 
 function is_crossing_free(a::ArcDiagram; part=:everything::Symbol)
     if part == :everything
@@ -182,23 +191,13 @@ function Base.show(io::IO, ::MIME"text/plain", a::ArcDiagramUndirected)
         return
     end
     symb_dict = Dict(v => s for (v, s) in zip(vertices(a), symbols))
-    function first_vertex(v1::ArcDiagramVertex, v2::ArcDiagramVertex)
-        if is_upper_vertex(v1) && is_lower_vertex(v2)
-            return v1
-        elseif is_lower_vertex(v1) && is_upper_vertex(v2)
-            return v2
-        else
-            return vertex_index(v1) <= vertex_index(v2) ? v1 : v2
-
-        end
-    end
-    print(io, join(symb_dict[first_vertex(v, neighbor(a, v))] for v in upper_vertices(a)))
+    print(io, join(symb_dict[_vertex_lt(v, neighbor(a, v)) ? v : neighbor(a, v)] for v in upper_vertices(a)))
     if get(io, :compact, false)
         print(io, ",")
     else
         print(io, "\n")
     end
-    print(io, join(symb_dict[first_vertex(v, neighbor(a, v))] for v in lower_vertices(a)))
+    print(io, join(symb_dict[_vertex_lt(v, neighbor(a, v)) ? v : neighbor(a, v)] for v in lower_vertices(a)))
 end
 
 function n_upper_vertices(a::ArcDiagramUndirected)
@@ -281,21 +280,10 @@ function Base.show(io::IO, ::MIME"text/plain", a::ArcDiagramDirected)
         return
     end
     symb_dict = Dict(v => (lowercase(s), s) for (v, s) in zip(vertices(a), symbols))
-    function first_vertex(v1::ArcDiagramVertex, v2::ArcDiagramVertex)
-        if is_upper_vertex(v1) && is_lower_vertex(v2)
-            return v1
-        elseif is_lower_vertex(v1) && is_upper_vertex(v2)
-            return v2
-        else
-            return vertex_index(v1) <= vertex_index(v2) ? v1 : v2
-
-        end
-    end
-
     print(
         io,
         join(
-            (a.parity_upper_verts[vertex_index(v)] ? first : last)(symb_dict[first_vertex(v, neighbor(a, v))]) for
+            (a.parity_upper_verts[vertex_index(v)] ? first : last)(symb_dict[_vertex_lt(v, neighbor(a, v)) ? v : neighbor(a, v)]) for
             v in upper_vertices(a)
         ),
     )
@@ -307,7 +295,7 @@ function Base.show(io::IO, ::MIME"text/plain", a::ArcDiagramDirected)
     print(
         io,
         join(
-            (!a.parity_lower_verts[vertex_index(v)] ? first : last)(symb_dict[first_vertex(v, neighbor(a, v))]) for
+            (!a.parity_lower_verts[vertex_index(v)] ? first : last)(symb_dict[_vertex_lt(v, neighbor(a, v)) ? v : neighbor(a, v)]) for
             v in lower_vertices(a)
         ),
     )

src/Misc.jl

@@ -10,3 +10,115 @@ function symmetrize(f::FreeAssAlgElem)
     end
     return g
 end
+
+function set_show_colorful_html(value::Bool)
+    old_value = get_show_colorful_html()
+    @set_preferences!("show_colorful_html" => value)
+    return old_value
+end
+
+function get_show_colorful_html()
+    return @load_preference("show_colorful_html", default = false)::Bool
+end
+
+Base.show(io::IO, ::MIME"text/html", A::ArcDiagram) = print(io, svg_string(A; colorful=get_show_colorful_html()))
+
+function svg_string_defs(::ArcDiagram)
+    return ""
+end
+
+function svg_string_defs(::ArcDiagramDirected)
+    # marker to be used as an arrowhead
+    return """
+        <marker id=\"arrow\" refX=\"2\" refY=\"2\" markerWidth=\"3\" markerHeight=\"4\" orient=\"auto\">
+            <path d=\"M 0 0 V 4 L 2 2 Z\" stroke=\"context-stroke\" fill=\"context-stroke\"/>
+        </marker>
+        """
+end
+
+function svg_string_edge_iterator(A::ArcDiagramUndirected)
+    return ((v, neighbor(A, v)) for v in vertices(A) if _vertex_lt(v, neighbor(A, v)))
+end
+
+function svg_string_edge_iterator(A::ArcDiagramDirected)
+    return ((v, outneighbor(A, v)) for v in vertices(A) if !isnothing(outneighbor(A, v)))
+end
+
+function svg_string_path(v::ArcDiagramVertex, nv::ArcDiagramVertex, dims)
+    (;margin, h, w) = dims
+    x_v = (vertex_index(v) - 1) * w + margin
+    x_nv = (vertex_index(nv) - 1) * w + margin
+    y_v = is_upper_vertex(v) ? margin : h + margin
+    y_nv = is_upper_vertex(nv) ? margin : h + margin
+
+    function y_c(x1, x2)
+        return (1-exp(-0.15*(1+abs(x1 - x2))))*0.85
+    end
+
+    if is_upper_vertex(v)
+        if is_upper_vertex(nv)
+            x_c1 = (8*x_v + 2*x_nv) / 10
+            y_c1 = y_c(vertex_index(v), vertex_index(nv)) * h + margin
+            x_c2 = (2*x_v + 8*x_nv) / 10
+            y_c2 = y_c(vertex_index(v), vertex_index(nv)) * h + margin
+            return "M $(x_v) $(y_v) C $(x_c1) $(y_c1), $(x_c2) $(y_c2), $(x_nv) $(y_nv)"
+        else
+            return "M $(x_v) $(y_v) L $(x_nv) $(y_nv)"
+        end
+    else
+        if is_upper_vertex(nv)
+            return "M $(x_v) $(y_v) L $(x_nv) $(y_nv)"
+        else
+            x_c1 = (8*x_v + 2*x_nv) / 10
+            y_c1 = (1 - y_c(vertex_index(v), vertex_index(nv))) * h + margin
+            x_c2 = (2*x_v + 8*x_nv) / 10
+            y_c2 = (1 - y_c(vertex_index(v), vertex_index(nv))) * h + margin
+            return "M $(x_v) $(y_v) C $(x_c1) $(y_c1), $(x_c2) $(y_c2), $(x_nv) $(y_nv)"
+        end
+    end
+end
+
+function svg_string(A::ArcDiagram; colorful=false)
+    color_mono = "#008"
+    size = 40
+    dims = (
+        rad=0.1*size,
+        margin=0.2*size,
+        h=1*size,
+        w=0.5*size,
+        stroke_width=2, #px
+    )
+
+    height = dims.h + 2 * dims.margin
+    width = (max(n_upper_vertices(A), n_lower_vertices(A)) - 1) * dims.w + 2 * dims.margin
+
+    svg = "<svg height=\"$(height)\" width=\"$(width)\" style=\"vertical-align:middle;\">"
+
+    svg *= "<defs>$(svg_string_defs(A))</defs>"
+
+    i = 0
+    for (v, nv) in svg_string_edge_iterator(A)
+        color = colorful ? "hsl($(105*i),100%,45%)" : color_mono
+        svg *= "<path d=\"$(svg_string_path(v, nv, dims))\" fill=\"transparent\" stroke=\"$color\" stroke-width=\"$(dims.stroke_width)px\" $(A isa ArcDiagramDirected ? "marker-end=\"url(#arrow)\"" : "")/>"
+        i += 1
+    end
+
+    svg *= "</svg>"
+    return svg
+end
+
+function Base.show(io::IO, mime::MIME"text/html", x::Tuple{Int,ArcDiagram})
+    print(io, "($(first(x)), ")
+    show(io, mime, x[2])
+    print(io, ")")
+end
+
+function Base.show(io::IO, mime::MIME"text/html", x::Tuple{ArcDiagram,Vararg{ArcDiagram}})
+    print(io, "<div>(")
+    show(io, mime, first(x))
+    for A in Base.tail(x)
+        print(io, ", ")
+        show(io, mime, A)
+    end
+    print(io, ")</div>")
+end

src/PBWDeformations.jl

@@ -1,5 +1,7 @@
 module PBWDeformations
 
+using Preferences: Preferences, @load_preference, @set_preferences!
+
 using Oscar
 
 using Oscar.AbstractAlgebra: ProductIterator
@@ -80,6 +82,7 @@ export edges
 export exterior_power
 export exterior_power_obj
 export general_linear_lie_algebra
+export get_show_colorful_html
 export inneighbor
 export inneighbors
 export is_crossing_free
@@ -101,6 +104,7 @@ export neighbors
 export outneighbor
 export outneighbors
 export pbwdeform_eqs
+export set_show_colorful_html
 export simple_module
 export smash_product
 export special_linear_lie_algebra