-- primitives for saving to file and loading from file
function file_exists(filename)
local infile = App.open_for_reading(filename)
if infile then
infile:close()
return true
else
return false
end
end
function load_from_disk(State)
local infile = App.open_for_reading(State.filename)
State.lines = load_from_file(infile)
if infile then infile:close() end
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(State)
local outfile = App.open_for_writing(State.filename)
if outfile == nil then
error('failed to write to "'..State.filename..'"')
end
for _,line in ipairs(State.lines) do
if line.mode == 'drawing' then
store_drawing(outfile, line)
else
outfile:write(line.data)
outfile:write('\n')
end
end
outfile:close()
end
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 == 'freehand' then
-- no changes needed
elseif shape.mode == 'line' or shape.mode == 'manhattan' then
local name = shape.p1.name
shape.p1 = Drawing.find_or_insert_point(drawing.points, shape.p1.x, shape.p1.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.p1].name = name
name = shape.p2.name
shape.p2 = Drawing.find_or_insert_point(drawing.points, shape.p2.x, shape.p2.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.p2].name = name
elseif shape.mode == 'polygon' or shape.mode == 'rectangle' or shape.mode == 'square' then
for i,p in ipairs(shape.vertices) do
local name = p.name
shape.vertices[i] = Drawing.find_or_insert_point(drawing.points, p.x,p.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.vertices[i]].name = name
end
elseif shape.mode == 'circle' or shape.mode == 'arc' then
local name = shape.center.name
shape.center = Drawing.find_or_insert_point(drawing.points, shape.center.x,shape.center.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.center].name = name
elseif shape.mode == 'deleted' then
-- ignore
else
print(shape.mode)
assert(false)
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' or shape.mode == 'rectangle' or shape.mode == 'square' 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')
elseif shape.mode == 'deleted' then
-- ignore
else
print(shape.mode)
assert(false)
end
end
outfile:write('```\n')
end
-- for tests
function load_array(a)
local result = {}
local next_line = ipairs(a)
local i,line,drawing = 0, ''
while true do
i,line = next_line(a, i)
if i == nil then break end
--? print(line)
if line == '```lines' then -- inflexible with whitespace since these files are always autogenerated
--? print('inserting drawing')
i, drawing = load_drawing_from_array(next_line, a, i)
--? print('i now', i)
table.insert(result, drawing)
else
--? print('inserting text')
table.insert(result, {mode='text', data=line})
end
end
if #result == 0 then
table.insert(result, {mode='text', data=''})
end
return result
end
function load_drawing_from_array(iter, a, i)
local drawing = {mode='drawing', h=256/2, points={}, shapes={}, pending={}}
local line
while true do
i, line = iter(a, i)
assert(i)
--? print(i)
if line == '```' then break end
local shape = json.decode(line)
if shape.mode == 'freehand' then
-- no changes needed
elseif shape.mode == 'line' or shape.mode == 'manhattan' then
local name = shape.p1.name
shape.p1 = Drawing.find_or_insert_point(drawing.points, shape.p1.x, shape.p1.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.p1].name = name
name = shape.p2.name
shape.p2 = Drawing.find_or_insert_point(drawing.points, shape.p2.x, shape.p2.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.p2].name = name
elseif shape.mode == 'polygon' or shape.mode == 'rectangle' or shape.mode == 'square' then
for i,p in ipairs(shape.vertices) do
local name = p.name
shape.vertices[i] = Drawing.find_or_insert_point(drawing.points, p.x,p.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.vertices[i]].name = name
end
elseif shape.mode == 'circle' or shape.mode == 'arc' then
local name = shape.center.name
shape.center = Drawing.find_or_insert_point(drawing.points, shape.center.x,shape.center.y, --[[large width to minimize overlap]] 1600)
drawing.points[shape.center].name = name
elseif shape.mode == 'deleted' then
-- ignore
else
print(shape.mode)
assert(false)
end
table.insert(drawing.shapes, shape)
end
return i, drawing
end
function is_absolute_path(path)
local os_path_separator = package.config:sub(1,1)
if os_path_separator == '/' then
-- POSIX systems permit backslashes in filenames
return path:sub(1,1) == '/'
elseif os_path_separator == '\\' then
if path:sub(2,2) == ':' then return true end -- DOS drive letter followed by volume separator
local f = path:sub(1,1)
return f == '/' or f == '\\'
else
error('What OS is this? LÖVE reports that the path separator is "'..os_path_separator..'"')
end
end
function is_relative_path(path)
return not is_absolute_path(path)
end