Drop seed label on gamut plot and add white-point legend entry

Author: kipcole9

lib/color/gamut/svg.ex

@@ -321,9 +321,7 @@ defmodule Color.Gamut.SVG do
 
     [
       "<circle cx=\"#{fmt(px)}\" cy=\"#{fmt(py)}\" r=\"7\" fill=\"#{hex}\" ",
-      "stroke=\"#fff\" stroke-width=\"2\" />",
-      "<text x=\"#{fmt(px + 10)}\" y=\"#{fmt(py + 4)}\" fill=\"#fff\" font-size=\"11\" ",
-      "font-family=\"ui-monospace,monospace\">seed</text>"
+      "stroke=\"#fff\" stroke-width=\"2\" />"
     ]
   end
 

lib/color/palette/visualizer.ex

@@ -196,11 +196,23 @@ defmodule Color.Palette.Visualizer do
         projection: atom_default(Map.get(params, "projection"), [:xy, :uv], :uv),
         gamuts: gamuts,
         planckian: truthy?(Map.get(params, "planckian")),
-        overlay_seed: truthy?(Map.get(params, "overlay_seed")),
-        overlay_palette: truthy?(Map.get(params, "overlay_palette"))
+        overlay_seed: checkbox_default(params, "overlay_seed", true),
+        overlay_palette: checkbox_default(params, "overlay_palette", true)
       }
     end
 
+    # A checkbox that defaults to `default_on` on fresh page loads
+    # but respects an explicit unchecked state after a form
+    # submission. We rely on the form's hidden `submitted` field
+    # to distinguish "never submitted" (fall back to default) from
+    # "submitted without this checkbox" (user unchecked it).
+    defp checkbox_default(params, key, default_on) do
+      case Map.get(params, key) do
+        nil -> not Map.has_key?(params, "submitted") and default_on
+        value -> truthy?(value)
+      end
+    end
+
     @gamut_atoms %{
       "SRGB" => :SRGB,
       "P3_D65" => :P3_D65,

lib/color/palette/visualizer/gamut_view.ex

@@ -168,6 +168,9 @@ defmodule Color.Palette.Visualizer.GamutView do
           ")</span></li>"
         ]
       end),
+      "<li><span class=\"vz-legend-swatch\" ",
+      "style=\"background:#60a5fa;border-radius:50%;border:1px solid rgba(255,255,255,0.4)\"></span>",
+      "White point of each gamut (dot inside its triangle)</li>",
       if show_planck do
         [
           "<li><span class=\"vz-legend-swatch\" style=\"background:#fbbf2433;border:1px dashed #fbbf24\"></span>Planckian locus (1500 – 20 000 K)</li>"

test/gamut_svg_test.exs

@@ -55,10 +55,9 @@ defmodule Color.Gamut.SVGTest do
       refute svg =~ "stroke-dasharray=\"3,3\""
     end
 
-    test "seed overlay plots a labelled dot" do
+    test "seed overlay plots a dot filled with the seed colour" do
       svg = SVG.render(seed: "#ff0000")
-      assert svg =~ ~s(>seed</text>)
-      assert svg =~ "#ff0000"
+      assert svg =~ ~s(fill="#ff0000")
     end
 
     test "palette overlay adds a circle per stop with <title>" do

test/palette_visualizer_test.exs

@@ -239,12 +239,12 @@ defmodule Color.Palette.VisualizerTest do
       assert on.resp_body =~ "stroke-dasharray=\"3,3\""
     end
 
-    test "overlay_seed plots a seed dot with label" do
+    test "overlay_seed plots a seed dot and adds a legend entry" do
       conn =
         conn(:get, "/gamut?overlay_seed=1&seed=%23ff0000&submitted=1")
         |> Color.Palette.Visualizer.call(@opts)
 
-      assert conn.resp_body =~ ~s(>seed</text>)
+      assert conn.resp_body =~ ~s(fill="#ff0000")
       assert conn.resp_body =~ "Seed:"
     end