From c501c4e6a419c2b0020101ccc9d8a449390ea671 Mon Sep 17 00:00:00 2001
From: Chidambaram Nachiappan
 <60850111+thechidambaram@users.noreply.github.com>
Date: Wed, 23 Feb 2022 21:42:19 +0000
Subject: Generate svg preview instead of png

---
 make_preview_image.lua | 32 +++++++++++---------------------
 1 file changed, 11 insertions(+), 21 deletions(-)

diff --git a/make_preview_image.lua b/make_preview_image.lua
index 31f088d..bf0d4ee 100755
--- a/make_preview_image.lua
+++ b/make_preview_image.lua
@@ -32,30 +32,20 @@ for i = #colors, 1, -1 do
 end
 
 
--- generate ppm file
+--generate svg file
 local w = 200
 local h = 16
-local fp = io.open(name .. ".ppm", "wb")
-fp:write("P3\n")
-fp:write(w, " ", h, "\n")
-fp:write("255\n")
-
-local row = {}
-for i = 0, w - 1 do
-  local idx = math.floor((#colors / w) * i) + 1
-  local r, g, b = table.unpack(colors[idx])
-  table.insert(row, r)
-  table.insert(row, g)
-  table.insert(row, b)
-end
-row = table.concat(row, " ") .. "\n"
+local fp = io.open(name .. ".svg", "wb")
+
+fp:write('<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="'..w..'" height="'..h..'"> \n')
 
-for i = 1, h do
-  fp:write(row)
+for i = 1, #colors do
+  local width = w/#colors
+  local r, g, b = table.unpack(colors[i])
+  local rect = '<rect x="'..(i-1)*width..'" width="'..width..'" height="'..h..'" fill="rgb('..r..', '..g..', '..b..')"></rect> \n'
+  fp:write(rect)
 end
-fp:close()
 
+fp:write('</svg>')
+fp:close()
 
--- convert ppm file to png
-os.execute(string.format("convert %s.ppm %s.png", name, name))
-os.execute(string.format("rm %s.ppm", name))
-- 
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