-- primitives for saving to file and loading from file
Drawing = require 'drawing'
function load_from_disk(filename)
local infile = io.open(filename)
local result = load_from_file(infile)
if infile then infile:close() end
return result
end
function load_from_file(infile)
local result = {}
if infile then
local infile_next_line = infile:lines() -- works with both Lua files and LÖVE Files (https://www.love2d.org/wiki/File)
while true do
local line = infile_next_line()
if line == nil then break end
if line == '```lines' then -- inflexible with whitespace since these files are always autogenerated
table.insert(result, load_drawing(infile_next_line))
else
table.insert(result, {mode='text', data=line})
end
end
end
if #result == 0 then
table.insert(result, {mode='text', data=''})
end
return result
end
function save_to_disk(lines, filename)
local outfile = io.open(filename, 'w')
for _,line in ipairs(lines) do
if line.mode == 'drawing' then
store_drawing(outfile, line)
else
outfile:write(line.data..'\n')
end
end
outfile:close()
end
json = require 'json'
function load_drawing(infile_next_line)
local drawing = {mode='drawing', h=256/2, points={}, shapes={}, pending={}}
while true do
local line = infile_next_line()
assert(line)
if line == '```' then break end
local shape = json.decode(line)
if shape.mode == 'line' or shape.mode == 'manhattan' then
shape.p1 = Drawing.insert_point(drawing.points, shape.p1.x, shape.p1.y)
shape.p2 = Drawing.insert_point(drawing.points, shape.p2.x, shape.p2.y)
elseif shape.mode == 'polygon' then
for i,p in ipairs(shape.vertices) do
shape.vertices[i] = Drawing.insert_point(drawing.points, p.x,p.y)
end
elseif shape.mode == 'circle' or shape.mode == 'arc' then
shape.center = Drawing.insert_point(drawing.points, shape.center.x,shape.center.y)
end
table.insert(drawing.shapes, shape)
end
return drawing
end
function store_drawing(outfile, drawing)
outfile:write('```lines\n')
for _,shape in ipairs(drawing.shapes) do
if shape.mode == 'freehand' then
outfile:write(json.encode(shape)..'\n')
elseif shape.mode == 'line' or shape.mode == 'manhattan' then
local line = json.encode({mode=shape.mode, p1=drawing.points[shape.p1], p2=drawing.points[shape.p2]})
outfile:write(line..'\n')
elseif shape.mode == 'polygon' then
local obj = {mode=shape.mode, vertices={}}
for _,p in ipairs(shape.vertices) do
table.insert(obj.vertices, drawing.points[p])
end
local line = json.encode(obj)
outfile:write(line..'\n')
elseif shape.mode == 'circle' then
outfile:write(json.encode({mode=shape.mode, center=drawing.points[shape.center], radius=shape.radius})..'\n')
elseif shape.mode == 'arc' then
outfile:write(json.encode({mode=shape.mode, center=drawing.points[shape.center], radius=shape.radius, start_angle=shape.start_angle, end_angle=shape.end_angle})..'\n')
end
end
outfile:write('```\n')
end