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require 'keychord'
require 'button'
require 'repl'
local utf8 = require 'utf8'
lines = {}
width, height, flags = 0, 0, nil
exec_payload = nil
function love.load()
table.insert(lines, '')
love.window.setMode(0, 0) -- maximize
width, height, flags = love.window.getMode()
love.keyboard.setTextInput(true) -- bring up keyboard on touch screen
end
function love.draw()
button_handlers = {}
love.graphics.setColor(1, 1, 1)
love.graphics.rectangle('fill', 1, 1, width-1, height-1)
love.graphics.setColor(0, 0, 0)
local text
local y = 0
for i, line in ipairs(lines) do
y = y+25
text = love.graphics.newText(love.graphics.getFont(), line)
if line == '' then
button('draw', {x=4,y=y+4, w=12,h=12, color={1,1,0},
icon = function(x,y)
love.graphics.setColor(0.7,0.7,0.7)
love.graphics.rectangle('line', x,y, 12,12)
love.graphics.line(4,y+6, 16,y+6)
love.graphics.line(10,y, 10,y+12)
love.graphics.setColor(0, 0, 0)
end,
onpress1 = function()
table.insert(lines, i, {y=y, w=400, h=200, pending={}, shapes={}})
end})
elseif type(line) == 'table' then
-- line drawing
love.graphics.setColor(0.75,0.75,0.75)
line.y = y
love.graphics.rectangle('line', 12,y, line.w,line.h)
y = y+line.h
for _,shape in ipairs(line.shapes) do
if on_freehand(love.mouse.getX(),love.mouse.getY(), shape) then
love.graphics.setColor(1,0,0)
else
love.graphics.setColor(0,0,0)
end
prev = nil
for _,point in ipairs(shape) do
if prev then
love.graphics.line(prev.x,prev.y, point.x,point.y)
end
prev = point
end
end
prev = nil
for _,point in ipairs(line.pending) do
if prev then
love.graphics.line(prev.x,prev.y, point.x,point.y)
end
prev = point
end
else
love.graphics.draw(text, 25,y, 0, 1.5)
end
end
-- cursor
love.graphics.print('_', 25+text:getWidth()*1.5, y)
-- display side effect
if exec_payload then
run(exec_payload)
end
end
function love.update(dt)
if love.mouse.isDown('1') then
if lines.current then
local drawing = lines.current
if type(drawing) == 'table' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + drawing.h and x >= 12 and x < 12+drawing.w then
table.insert(drawing.pending, {x=love.mouse.getX(), y=love.mouse.getY()})
end
end
end
end
end
function love.mousepressed(x,y, button)
propagate_to_button_handers(x,y, button)
propagate_to_drawings(x,y, button)
end
function propagate_to_drawings(x,y, button)
for i,drawing in ipairs(lines) do
if type(drawing) == 'table' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + drawing.h and x >= 12 and x < 12+drawing.w then
lines.current = drawing
end
end
end
end
function on_freehand(x,y, shape)
local prev
for _,p in ipairs(shape) do
if prev then
if on_line(x,y, {x1=prev.x,y1=prev.y, x2=p.x,y2=p.y}) then
return true
end
end
prev = p
end
return false
end
function on_line(x,y, shape)
if shape.x1 == shape.x2 then
local y1,y2 = shape.y1,shape.y2
if y1 > y2 then
y1,y2 = y2,y2
end
return y >= y1 and y <= y2
end
-- has the right slope and intercept
local m = (shape.y2 - shape.y1) / (shape.x2 - shape.x1)
local yp = shape.y1 + m*(x-shape.x1)
if yp < 0.95*y or yp > 1.05*y then
return false
end
-- between endpoints
local k = (x-shape.x1) / (shape.x2-shape.x1)
return k > -0.05 and k < 1.05
end
function love.mousereleased(x,y, button)
if lines.current then
if lines.current.pending then
table.insert(lines.current.shapes, lines.current.pending)
lines.current.pending = {}
lines.current = nil
end
end
end
function love.textinput(t)
lines[#lines] = lines[#lines]..t
end
function keychord_pressed(chord)
-- Don't handle any keys here that would trigger love.textinput above.
if chord == 'return' then
table.insert(lines, '')
elseif chord == 'backspace' then
if #lines > 1 and lines[#lines] == '' then
table.remove(lines)
else
local byteoffset = utf8.offset(lines[#lines], -1)
if byteoffset then
lines[#lines] = string.sub(lines[#lines], 1, byteoffset-1)
end
end
elseif chord == 'C-r' then
lines[#lines+1] = eval(lines[#lines])[1]
lines[#lines+1] = ''
elseif chord == 'C-d' then
parse_into_exec_payload(lines[#lines])
elseif chord == 'C-l' then
local drawing,i,shape = select_shape_at_mouse()
if drawing then
convert_line(drawing,i,shape)
end
elseif chord == 'C-m' then
local drawing,i,shape = select_shape_at_mouse()
if drawing then
convert_horvert(drawing,i,shape)
end
end
end
function select_shape_at_mouse()
for _,drawing in ipairs(lines) do
if type(drawing) == 'table' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + drawing.h and x >= 12 and x < 12+drawing.w then
for i,shape in ipairs(drawing.shapes) do
if on_freehand(love.mouse.getX(),love.mouse.getY(), shape) then
return drawing,i,shape
end
end
end
end
end
end
function convert_line(drawing, i, shape)
-- Perhaps we should do a more sophisticated "simple linear regression"
-- here:
-- https://en.wikipedia.org/wiki/Linear_regression#Simple_and_multiple_linear_regression
-- But this works well enough for close-to-linear strokes.
drawing.shapes[i] = {shape[1], shape[#shape]}
end
-- turn a stroke into either a horizontal or vertical line
function convert_horvert(drawing, i, shape)
local x1,y1 = shape[1].x, shape[1].y
local x2,y2 = shape[#shape].x, shape[#shape].y
if math.abs(x1-x2) > math.abs(y1-y2) then
drawing.shapes[i] = {{x=x1, y=y1}, {x=x2, y=y1}}
else
drawing.shapes[i] = {{x=x1, y=y1}, {x=x1, y=y2}}
end
end
function love.keyreleased(key, scancode)
end
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