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|
local utf8 = require 'utf8'
require 'keychord'
require 'button'
local Drawing = require 'drawing'
-- a line is either text or a drawing
-- a text is a table with:
-- mode = 'text'
-- string data
-- a drawing is a table with:
-- mode = 'drawing'
-- a (y) coord in pixels (updated while painting screen),
-- a (h)eight,
-- an array of points, and
-- an array of shapes
-- a shape is a table containing:
-- a mode
-- an array points for mode 'freehand' (raw x,y coords; freehand drawings don't pollute the points array of a drawing)
-- an array vertices for mode 'polygon', 'rectangle', 'square'
-- p1, p2 for mode 'line'
-- p1, p2, arrow-mode for mode 'arrow-line'
-- center, radius for mode 'circle'
-- center, radius, start_angle, end_angle for mode 'arc'
-- Unless otherwise specified, coord fields are normalized; a drawing is always 256 units wide
-- The field names are carefully chosen so that switching modes in midstream
-- remembers previously entered points where that makes sense.
--
-- Open question: how to maintain Sketchpad-style constraints? Answer for now:
-- we don't. Constraints operate only for the duration of a drawing operation.
-- We'll continue to persist them just to keep the option open to continue
-- solving for them. But for now, this is a program to create static drawings
-- once, and read them passively thereafter.
Lines = {{mode='text', data=''}}
Cursor_line = 1
-- this is a line
-- ^cursor_pos = 1
-- ^cursor_pos = 2
-- ...
-- ^cursor_pos past end of line is 15
Cursor_pos = #Lines[Cursor_line].data+1
Screen_width, Screen_height, Screen_flags = 0, 0, nil
Current_mode = 'line'
Previous_mode = nil
-- All drawings span 100% of some conceptual 'page width' and divide it up
-- into 256 parts. `Drawing_width` describes their width in pixels.
Drawing_width = nil -- pixels
function pixels(n) -- parts to pixels
return n*Drawing_width/256
end
function coord(n) -- pixels to parts
return math.floor(n*256/Drawing_width)
end
Zoom = 1.5
Filename = 'lines.txt'
function love.load(arg)
-- maximize window
love.window.setMode(0, 0) -- maximize
Screen_width, Screen_height, Screen_flags = love.window.getMode()
-- shrink slightly to account for window decoration
Screen_width = Screen_width-100
Screen_height = Screen_height-100
love.window.setMode(Screen_width, Screen_height)
love.window.setTitle('Text with Lines')
Drawing_width = math.floor(Screen_width/2/40)*40
love.keyboard.setTextInput(true) -- bring up keyboard on touch screen
if #arg > 0 then
Filename = arg[1]
end
Lines = load_from_disk(Filename)
for i,line in ipairs(Lines) do
if line.mode == 'text' then
Cursor_line = i
end
end
love.window.setTitle('Text with Lines - '..Filename)
end
function love.filedropped(file)
Filename = file:getFilename()
file:open('r')
Lines = load_from_file(file)
file:close()
for i,line in ipairs(Lines) do
if line.mode == 'text' then
Cursor_line = i
end
end
love.window.setTitle('Text with Lines - '..Filename)
end
function love.draw()
button_handlers = {}
love.graphics.setColor(1, 1, 1)
love.graphics.rectangle('fill', 0, 0, Screen_width-1, Screen_height-1)
love.graphics.setColor(0, 0, 0)
local y = 0
for line_index,line in ipairs(Lines) do
y = y+15*Zoom
line.y = y
if line.mode == 'text' and line.data == '' then
button('draw', {x=4,y=y+4, w=12,h=12, color={1,1,0},
icon = icon.insert_drawing,
onpress1 = function()
table.insert(Lines, line_index, {mode='drawing', y=y, h=256/2, points={}, shapes={}, pending={}})
if Cursor_line >= line_index then
Cursor_line = Cursor_line+1
end
end})
if line_index == Cursor_line then
love.graphics.setColor(0,0,0)
love.graphics.print('_', 25, y+6) -- drop the cursor down a bit to account for the increased font size
end
elseif line.mode == 'drawing' then
y = y+pixels(line.h)
Drawing.draw(line, y)
else
love.graphics.setColor(0,0,0)
local text = love.graphics.newText(love.graphics.getFont(), line.data)
love.graphics.draw(text, 25,y, 0, Zoom)
if line_index == Cursor_line then
-- cursor
love.graphics.print('_', cursor_x(line.data, Cursor_pos), y+6) -- drop the cursor down a bit to account for the increased font size
end
end
end
end
function love.update(dt)
if love.mouse.isDown('1') then
if Lines.current then
if Lines.current.mode == 'drawing' then
local drawing = Lines.current
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
if drawing.pending.mode == 'freehand' then
table.insert(drawing.pending.points, {x=coord(love.mouse.getX()-16), y=coord(love.mouse.getY()-drawing.y)})
elseif drawing.pending.mode == 'move' then
local mx,my = coord(x-16), coord(y-drawing.y)
drawing.pending.target_point.x = mx
drawing.pending.target_point.y = my
end
end
end
end
elseif Current_mode == 'move' then
local drawing = Lines.current
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
local mx,my = coord(x-16), coord(y-drawing.y)
drawing.pending.target_point.x = mx
drawing.pending.target_point.y = my
end
end
end
function love.mousepressed(x,y, button)
propagate_to_button_handlers(x,y, button)
for line_index,line in ipairs(Lines) do
if line.mode == 'text' then
-- move cursor
if x >= 16 and y >= line.y and y < y+15*Zoom then
Cursor_line = line_index
Cursor_pos = nearest_cursor_pos(line.data, x, 1)
end
elseif line.mode == 'drawing' then
local drawing = line
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
if Current_mode == 'freehand' then
drawing.pending = {mode=Current_mode, points={{x=coord(x-16), y=coord(y-drawing.y)}}}
elseif Current_mode == 'line' or Current_mode == 'manhattan' then
local j = insert_point(drawing.points, coord(x-16), coord(y-drawing.y))
drawing.pending = {mode=Current_mode, p1=j}
elseif Current_mode == 'polygon' then
local j = insert_point(drawing.points, coord(x-16), coord(y-drawing.y))
drawing.pending = {mode=Current_mode, vertices={j}}
elseif Current_mode == 'circle' then
local j = insert_point(drawing.points, coord(x-16), coord(y-drawing.y))
drawing.pending = {mode=Current_mode, center=j}
end
Lines.current = drawing
end
end
end
end
function love.mousereleased(x,y, button)
if Current_mode == 'move' then
Current_mode = Previous_mode
Previous_mode = nil
elseif Lines.current then
if Lines.current.pending then
if Lines.current.pending.mode == 'freehand' then
-- the last point added during update is good enough
table.insert(Lines.current.shapes, Lines.current.pending)
elseif Lines.current.pending.mode == 'line' then
local mx,my = coord(x-16), coord(y-Lines.current.y)
if mx >= 0 and mx < 256 and my >= 0 and my < Lines.current.h then
local j = insert_point(Lines.current.points, mx,my)
Lines.current.pending.p2 = j
table.insert(Lines.current.shapes, Lines.current.pending)
end
elseif Lines.current.pending.mode == 'manhattan' then
local p1 = Lines.current.points[Lines.current.pending.p1]
local mx,my = coord(x-16), coord(y-Lines.current.y)
if mx >= 0 and mx < 256 and my >= 0 and my < Lines.current.h then
if math.abs(mx-p1.x) > math.abs(my-p1.y) then
local j = insert_point(Lines.current.points, mx, p1.y)
Lines.current.pending.p2 = j
else
local j = insert_point(Lines.current.points, p1.x, my)
Lines.current.pending.p2 = j
end
local p2 = Lines.current.points[Lines.current.pending.p2]
love.mouse.setPosition(16+pixels(p2.x), Lines.current.y+pixels(p2.y))
table.insert(Lines.current.shapes, Lines.current.pending)
end
elseif Lines.current.pending.mode == 'polygon' then
local mx,my = coord(x-16), coord(y-Lines.current.y)
if mx >= 0 and mx < 256 and my >= 0 and my < Lines.current.h then
local j = insert_point(Lines.current.points, mx,my)
table.insert(Lines.current.shapes, Lines.current.pending)
end
table.insert(Lines.current.shapes, Lines.current.pending)
elseif Lines.current.pending.mode == 'circle' then
local mx,my = coord(x-16), coord(y-Lines.current.y)
if mx >= 0 and mx < 256 and my >= 0 and my < Lines.current.h then
local center = Lines.current.points[Lines.current.pending.center]
Lines.current.pending.radius = math.dist(center.x,center.y, mx,my)
table.insert(Lines.current.shapes, Lines.current.pending)
end
elseif Lines.current.pending.mode == 'arc' then
local mx,my = coord(x-16), coord(y-Lines.current.y)
if mx >= 0 and mx < 256 and my >= 0 and my < Lines.current.h then
local center = Lines.current.points[Lines.current.pending.center]
Lines.current.pending.end_angle = angle_with_hint(center.x,center.y, mx,my, Lines.current.pending.end_angle)
table.insert(Lines.current.shapes, Lines.current.pending)
end
end
Lines.current.pending = {}
Lines.current = nil
end
end
if Filename then
save_to_disk(Lines, Filename)
end
end
function insert_point(points, x,y)
for i,point in ipairs(points) do
if near(point, x,y) then
return i
end
end
table.insert(points, {x=x, y=y})
return #points
end
function near(point, x,y)
local px,py = pixels(x),pixels(y)
local cx,cy = pixels(point.x), pixels(point.y)
return (cx-px)*(cx-px) + (cy-py)*(cy-py) < 16
end
function draw_shape(left,top, drawing, shape)
if shape.mode == 'freehand' then
local prev = nil
for _,point in ipairs(shape.points) do
if prev then
love.graphics.line(pixels(prev.x)+left,pixels(prev.y)+top, pixels(point.x)+left,pixels(point.y)+top)
end
prev = point
end
elseif shape.mode == 'line' or shape.mode == 'manhattan' then
local p1 = drawing.points[shape.p1]
local p2 = drawing.points[shape.p2]
love.graphics.line(pixels(p1.x)+left,pixels(p1.y)+top, pixels(p2.x)+left,pixels(p2.y)+top)
elseif shape.mode == 'polygon' then
local prev = nil
for _,point in ipairs(shape.vertices) do
local curr = drawing.points[point]
if prev then
love.graphics.line(pixels(prev.x)+left,pixels(prev.y)+top, pixels(curr.x)+left,pixels(curr.y)+top)
end
prev = curr
end
-- close the loop
local curr = drawing.points[shape.vertices[1]]
love.graphics.line(pixels(prev.x)+left,pixels(prev.y)+top, pixels(curr.x)+left,pixels(curr.y)+top)
elseif shape.mode == 'circle' then
local center = drawing.points[shape.center]
love.graphics.circle('line', pixels(center.x)+left,pixels(center.y)+top, pixels(shape.radius))
elseif shape.mode == 'arc' then
local center = drawing.points[shape.center]
love.graphics.arc('line', 'open', pixels(center.x)+left,pixels(center.y)+top, pixels(shape.radius), shape.start_angle, shape.end_angle, 360)
elseif shape.mode == 'deleted' then
else
print(shape.mode)
assert(false)
end
end
function draw_pending_shape(left,top, drawing)
local shape = drawing.pending
if shape.mode == 'freehand' then
draw_shape(left,top, drawing, shape)
elseif shape.mode == 'line' then
local p1 = drawing.points[shape.p1]
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then
return
end
love.graphics.line(pixels(p1.x)+left,pixels(p1.y)+top, pixels(mx)+left,pixels(my)+top)
elseif shape.mode == 'manhattan' then
local p1 = drawing.points[shape.p1]
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then
return
end
if math.abs(mx-p1.x) > math.abs(my-p1.y) then
love.graphics.line(pixels(p1.x)+left,pixels(p1.y)+top, pixels(mx)+left,pixels(p1.y)+top)
else
love.graphics.line(pixels(p1.x)+left,pixels(p1.y)+top, pixels(p1.x)+left,pixels(my)+top)
end
elseif shape.mode == 'polygon' then
-- don't close the loop on a pending polygon
local prev = nil
for _,point in ipairs(shape.vertices) do
local curr = drawing.points[point]
if prev then
love.graphics.line(pixels(prev.x)+left,pixels(prev.y)+top, pixels(curr.x)+left,pixels(curr.y)+top)
end
prev = curr
end
love.graphics.line(pixels(prev.x)+left,pixels(prev.y)+top, love.mouse.getX(),love.mouse.getY())
elseif shape.mode == 'circle' then
local center = drawing.points[shape.center]
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then
return
end
local cx,cy = pixels(center.x)+left, pixels(center.y)+top
love.graphics.circle('line', cx,cy, math.dist(cx,cy, love.mouse.getX(),love.mouse.getY()))
elseif shape.mode == 'arc' then
local center = drawing.points[shape.center]
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then
return
end
shape.end_angle = angle_with_hint(center.x,center.y, mx,my, shape.end_angle)
local cx,cy = pixels(center.x)+left, pixels(center.y)+top
love.graphics.arc('line', 'open', cx,cy, pixels(shape.radius), shape.start_angle, shape.end_angle, 360)
end
end
function on_shape(x,y, drawing, shape)
if shape.mode == 'freehand' then
return on_freehand(x,y, drawing, shape)
elseif shape.mode == 'line' then
return on_line(x,y, drawing, shape)
elseif shape.mode == 'manhattan' then
return x == drawing.points[shape.p1].x or y == drawing.points[shape.p1].y
elseif shape.mode == 'polygon' then
return on_polygon(x,y, drawing, shape)
elseif shape.mode == 'circle' then
local center = drawing.points[shape.center]
return math.dist(center.x,center.y, x,y) == shape.radius
elseif shape.mode == 'arc' then
local center = drawing.points[shape.center]
local dist = math.dist(center.x,center.y, x,y)
if dist < shape.radius*0.95 or dist > shape.radius*1.05 then
return false
end
return angle_between(center.x,center.y, x,y, shape.start_angle,shape.end_angle)
elseif shape.mode == 'deleted' then
else
print(shape.mode)
assert(false)
end
end
function on_freehand(x,y, drawing, shape)
local prev
for _,p in ipairs(shape.points) do
if prev then
if on_line(x,y, drawing, {p1=prev, p2=p}) then
return true
end
end
prev = p
end
return false
end
function on_line(x,y, drawing, shape)
local p1,p2
if type(shape.p1) == 'number' then
p1 = drawing.points[shape.p1]
p2 = drawing.points[shape.p2]
else
p1 = shape.p1
p2 = shape.p2
end
if p1.x == p2.x then
if math.abs(p1.x-x) > 5 then
return false
end
local y1,y2 = p1.y,p2.y
if y1 > y2 then
y1,y2 = y2,y1
end
return y >= y1 and y <= y2
end
-- has the right slope and intercept
local m = (p2.y - p1.y) / (p2.x - p1.x)
local yp = p1.y + m*(x-p1.x)
if yp < 0.95*y or yp > 1.05*y then
return false
end
-- between endpoints
local k = (x-p1.x) / (p2.x-p1.x)
return k > -0.05 and k < 1.05
end
function on_polygon(x,y, drawing, shape)
local prev
for _,p in ipairs(shape.vertices) do
if prev then
if on_line(x,y, drawing, {p1=prev, p2=p}) then
return true
end
end
prev = p
end
return on_line(x,y, drawing, {p1=shape.vertices[1], p2=shape.vertices[#shape.vertices]})
end
function angle_between(x1,y1, x2,y2, s,e)
local angle = math.angle(x1,y1, x2,y2)
if s > e then
s,e = e,s
end
-- I'm not sure this is right or ideal..
angle = angle-math.pi*2
if s <= angle and angle <= e then
return true
end
angle = angle+math.pi*2
if s <= angle and angle <= e then
return true
end
angle = angle+math.pi*2
return s <= angle and angle <= e
end
function love.textinput(t)
if love.mouse.isDown('1') then return end
if Lines[Cursor_line].mode == 'drawing' then return end
local byteoffset
if Cursor_pos > 1 then
byteoffset = utf8.offset(Lines[Cursor_line].data, Cursor_pos-1)
else
byteoffset = 0
end
Lines[Cursor_line].data = string.sub(Lines[Cursor_line].data, 1, byteoffset)..t..string.sub(Lines[Cursor_line].data, byteoffset+1)
Cursor_pos = Cursor_pos+1
if Filename then
save_to_disk(Lines, Filename)
end
end
function keychord_pressed(chord)
-- Don't handle any keys here that would trigger love.textinput above.
-- shortcuts for text
if chord == 'return' then
table.insert(Lines, Cursor_line+1, {mode='text', data=''})
Cursor_line = Cursor_line+1
Cursor_pos = 1
elseif chord == 'backspace' then
if Cursor_pos > 1 then
local byte_start = utf8.offset(Lines[Cursor_line].data, Cursor_pos-1)
local byte_end = utf8.offset(Lines[Cursor_line].data, Cursor_pos)
if byte_start then
if byte_end then
Lines[Cursor_line].data = string.sub(Lines[Cursor_line].data, 1, byte_start-1)..string.sub(Lines[Cursor_line].data, byte_end)
else
Lines[Cursor_line].data = string.sub(Lines[Cursor_line].data, 1, byte_start-1)
end
Cursor_pos = Cursor_pos-1
end
elseif Cursor_line > 1 then
if Lines[Cursor_line-1].mode == 'drawing' then
table.remove(Lines, Cursor_line-1)
else
-- join Lines
Cursor_pos = utf8.len(Lines[Cursor_line-1].data)+1
Lines[Cursor_line-1].data = Lines[Cursor_line-1].data..Lines[Cursor_line].data
table.remove(Lines, Cursor_line)
end
Cursor_line = Cursor_line-1
end
elseif chord == 'left' then
if Cursor_pos > 1 then
Cursor_pos = Cursor_pos-1
end
elseif chord == 'right' then
if Cursor_pos <= #Lines[Cursor_line].data then
Cursor_pos = Cursor_pos+1
end
elseif chord == 'home' then
Cursor_pos = 1
elseif chord == 'end' then
Cursor_pos = #Lines[Cursor_line].data+1
elseif chord == 'delete' then
if Cursor_pos <= #Lines[Cursor_line].data then
local byte_start = utf8.offset(Lines[Cursor_line].data, Cursor_pos)
local byte_end = utf8.offset(Lines[Cursor_line].data, Cursor_pos+1)
if byte_start then
if byte_end then
Lines[Cursor_line].data = string.sub(Lines[Cursor_line].data, 1, byte_start-1)..string.sub(Lines[Cursor_line].data, byte_end)
else
Lines[Cursor_line].data = string.sub(Lines[Cursor_line].data, 1, byte_start-1)
end
-- no change to Cursor_pos
end
end
-- transitioning between drawings and text
elseif chord == 'up' then
assert(Lines[Cursor_line].mode == 'text')
local new_cursor_line = Cursor_line
while new_cursor_line > 1 do
new_cursor_line = new_cursor_line-1
if Lines[new_cursor_line].mode == 'text' then
local old_x = cursor_x(Lines[new_cursor_line].data, Cursor_pos)
Cursor_line = new_cursor_line
Cursor_pos = nearest_cursor_pos(Lines[Cursor_line].data, old_x, Cursor_pos)
break
end
end
elseif chord == 'down' then
assert(Lines[Cursor_line].mode == 'text')
local new_cursor_line = Cursor_line
while new_cursor_line < #Lines do
new_cursor_line = new_cursor_line+1
if Lines[new_cursor_line].mode == 'text' then
local old_x = cursor_x(Lines[new_cursor_line].data, Cursor_pos)
Cursor_line = new_cursor_line
Cursor_pos = nearest_cursor_pos(Lines[Cursor_line].data, old_x, Cursor_pos)
break
end
end
elseif chord == 'C-=' then
Drawing_width = Drawing_width/Zoom
Zoom = Zoom+0.5
Drawing_width = Drawing_width*Zoom
elseif chord == 'C--' then
Drawing_width = Drawing_width/Zoom
Zoom = Zoom-0.5
Drawing_width = Drawing_width*Zoom
elseif chord == 'C-0' then
Drawing_width = Drawing_width/Zoom
Zoom = 1.5
Drawing_width = Drawing_width*Zoom
-- shortcuts for drawings
elseif chord == 'escape' and love.mouse.isDown('1') then
local drawing = current_drawing()
drawing.pending = {}
elseif chord == 'C-f' and not love.mouse.isDown('1') then
Current_mode = 'freehand'
elseif chord == 'C-g' and not love.mouse.isDown('1') then
Current_mode = 'polygon'
elseif love.mouse.isDown('1') and chord == 'g' then
Current_mode = 'polygon'
local drawing = current_drawing()
if drawing.pending.mode == 'freehand' then
drawing.pending.vertices = {insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)}
elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then
if drawing.pending.vertices == nil then
drawing.pending.vertices = {drawing.pending.p1}
end
elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then
drawing.pending.vertices = {drawing.pending.center}
end
drawing.pending.mode = 'polygon'
elseif love.mouse.isDown('1') and chord == 'p' and Current_mode == 'polygon' then
local drawing = current_drawing()
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
local j = insert_point(drawing.points, mx,my)
table.insert(drawing.pending.vertices, j)
elseif chord == 'C-c' and not love.mouse.isDown('1') then
Current_mode = 'circle'
elseif love.mouse.isDown('1') and chord == 'a' and Current_mode == 'circle' then
local drawing = current_drawing()
drawing.pending.mode = 'arc'
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
local j = insert_point(drawing.points, mx,my)
local center = drawing.points[drawing.pending.center]
drawing.pending.radius = math.dist(center.x,center.y, mx,my)
drawing.pending.start_angle = math.angle(center.x,center.y, mx,my)
elseif love.mouse.isDown('1') and chord == 'c' then
Current_mode = 'circle'
local drawing = current_drawing()
if drawing.pending.mode == 'freehand' then
drawing.pending.center = insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)
elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then
drawing.pending.center = drawing.pending.p1
elseif drawing.pending.mode == 'polygon' then
drawing.pending.center = drawing.pending.vertices[1]
end
drawing.pending.mode = 'circle'
elseif love.mouse.isDown('1') and chord == 'l' then
Current_mode = 'line'
local drawing = current_drawing()
if drawing.pending.mode == 'freehand' then
drawing.pending.p1 = insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)
elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then
drawing.pending.p1 = drawing.pending.center
elseif drawing.pending.mode == 'polygon' then
drawing.pending.p1 = drawing.pending.vertices[1]
end
drawing.pending.mode = 'line'
elseif chord == 'C-l' then
Current_mode = 'line'
local drawing,_,shape = select_shape_at_mouse()
if drawing then
convert_line(drawing, shape)
end
elseif love.mouse.isDown('1') and chord == 'm' then
Current_mode = 'manhattan'
local drawing = select_drawing_at_mouse()
if drawing.pending.mode == 'freehand' then
drawing.pending.p1 = insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)
elseif drawing.pending.mode == 'line' then
-- do nothing
elseif drawing.pending.mode == 'polygon' then
drawing.pending.p1 = drawing.pending.vertices[1]
elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then
drawing.pending.p1 = drawing.pending.center
end
drawing.pending.mode = 'manhattan'
elseif chord == 'C-m' and not love.mouse.isDown('1') then
Current_mode = 'manhattan'
local drawing,_,shape = select_shape_at_mouse()
if drawing then
convert_horvert(drawing, shape)
end
elseif chord == 'C-s' and not love.mouse.isDown('1') then
local drawing,_,shape = select_shape_at_mouse()
if drawing then
smoothen(shape)
end
elseif chord == 'C-v' and not love.mouse.isDown('1') then
local drawing,_,p = select_point_at_mouse()
if drawing then
Previous_mode = Current_mode
Current_mode = 'move'
drawing.pending = {mode=Current_mode, target_point=p}
Lines.current = drawing
end
elseif love.mouse.isDown('1') and chord == 'v' then
local drawing,_,p = select_point_at_mouse()
if drawing then
Previous_mode = Current_mode
Current_mode = 'move'
drawing.pending = {mode=Current_mode, target_point=p}
Lines.current = drawing
end
elseif chord == 'C-d' and not love.mouse.isDown('1') then
local drawing,i,p = select_point_at_mouse()
if drawing then
for _,shape in ipairs(drawing.shapes) do
if contains_point(shape, i) then
if shape.mode == 'polygon' then
local idx = table.find(shape.vertices, i)
assert(idx)
table.remove(shape.vertices, idx)
if #shape.vertices < 3 then
shape.mode = 'deleted'
end
else
shape.mode = 'deleted'
end
end
end
drawing.points[i].deleted = true
end
local drawing,_,shape = select_shape_at_mouse()
if drawing then
shape.mode = 'deleted'
end
elseif chord == 'C-h' and not love.mouse.isDown('1') then
local drawing = select_drawing_at_mouse()
if drawing then
drawing.show_help = true
end
elseif chord == 'escape' and not love.mouse.isDown('1') then
for _,line in ipairs(Lines) do
if line.mode == 'drawing' then
line.show_help = false
end
end
end
end
function cursor_x(line, cursor_pos)
local line_before_cursor = line:sub(1, cursor_pos-1)
local text_before_cursor = love.graphics.newText(love.graphics.getFont(), line_before_cursor)
return 25+text_before_cursor:getWidth()*Zoom
end
function nearest_cursor_pos(line, x, hint)
if x == 0 then
return 1
end
local max_x = cursor_x(line, #line+1)
if x > max_x then
return #line+1
end
local currx = cursor_x(line, hint)
if currx > x-2 and currx < x+2 then
return hint
end
local left, right = 1, #line+1
if currx > x then
right = hint
else
left = hint
end
while left < right-1 do
local curr = math.floor((left+right)/2)
local currxmin = cursor_x(line, curr)
local currxmax = cursor_x(line, curr+1)
if currxmin <= x and x < currxmax then
return curr
end
if currxmin > x then
right = curr
else
left = curr
end
end
return right
end
function current_drawing()
local x, y = love.mouse.getX(), love.mouse.getY()
for _,drawing in ipairs(Lines) do
if drawing.mode == 'drawing' then
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
return drawing
end
end
end
return nil
end
function select_shape_at_mouse()
for _,drawing in ipairs(Lines) do
if drawing.mode == 'drawing' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
for i,shape in ipairs(drawing.shapes) do
assert(shape)
if on_shape(mx,my, drawing, shape) then
return drawing,i,shape
end
end
end
end
end
end
function select_point_at_mouse()
for _,drawing in ipairs(Lines) do
if drawing.mode == 'drawing' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
local mx,my = coord(love.mouse.getX()-16), coord(love.mouse.getY()-drawing.y)
for i,point in ipairs(drawing.points) do
assert(point)
if near(point, mx,my) then
return drawing,i,point
end
end
end
end
end
end
function select_drawing_at_mouse()
for _,drawing in ipairs(Lines) do
if drawing.mode == 'drawing' then
local x, y = love.mouse.getX(), love.mouse.getY()
if y >= drawing.y and y < drawing.y + pixels(drawing.h) and x >= 16 and x < 16+Drawing_width then
return drawing
end
end
end
end
function contains_point(shape, p)
if shape.mode == 'freehand' then
-- not supported
elseif shape.mode == 'line' or shape.mode == 'manhattan' then
return shape.p1 == p or shape.p2 == p
elseif shape.mode == 'polygon' then
return table.find(shape.vertices, p)
elseif shape.mode == 'circle' then
return shape.center == p
elseif shape.mode == 'arc' then
return shape.center == p
-- ugh, how to support angles
elseif shape.mode == 'deleted' then
-- already done
else
print(shape.mode)
assert(false)
end
end
function convert_line(drawing, 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.
assert(shape.mode == 'freehand')
shape.mode = 'line'
shape.p1 = insert_point(drawing.points, shape.points[1].x, shape.points[1].y)
local n = #shape.points
shape.p2 = insert_point(drawing.points, shape.points[n].x, shape.points[n].y)
end
-- turn a line either horizontal or vertical
function convert_horvert(drawing, shape)
if shape.mode == 'freehand' then
convert_line(shape)
end
assert(shape.mode == 'line')
local p1 = drawing.points[shape.p1]
local p2 = drawing.points[shape.p2]
if math.abs(p1.x-p2.x) > math.abs(p1.y-p2.y) then
p2.y = p1.y
else
p2.x = p1.x
end
end
function smoothen(shape)
assert(shape.mode == 'freehand')
for _=1,7 do
for i=2,#shape.points-1 do
local a = shape.points[i-1]
local b = shape.points[i]
local c = shape.points[i+1]
b.x = (a.x + b.x + c.x)/3
b.y = (a.y + b.y + c.y)/3
end
end
end
function love.keyreleased(key, scancode)
end
function table.find(h, x)
for k,v in pairs(h) do
if v == x then
return k
end
end
end
function angle_with_hint(x1, y1, x2, y2, hint)
local result = math.angle(x1,y1, x2,y2)
if hint then
-- Smooth the discontinuity where angle goes from positive to negative.
-- The hint is a memory of which way we drew it last time.
while result > hint+math.pi/10 do
result = result-math.pi*2
end
while result < hint-math.pi/10 do
result = result+math.pi*2
end
end
return result
end
-- result is from -π/2 to 3π/2, approximately adding math.atan2 from Lua 5.3
-- (LÖVE is Lua 5.1)
function math.angle(x1,y1, x2,y2)
local result = math.atan((y2-y1)/(x2-x1))
if x2 < x1 then
result = result+math.pi
end
return result
end
function math.dist(x1,y1, x2,y2) return ((x2-x1)^2+(y2-y1)^2)^0.5 end
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 = insert_point(drawing.points, shape.p1.x, shape.p1.y)
shape.p2 = 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] = insert_point(drawing.points, p.x,p.y)
end
elseif shape.mode == 'circle' or shape.mode == 'arc' then
shape.center = 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
icon = {}
function icon.insert_drawing(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
function icon.freehand(x, y)
love.graphics.line(x+4,y+7,x+5,y+5)
love.graphics.line(x+5,y+5,x+7,y+4)
love.graphics.line(x+7,y+4,x+9,y+3)
love.graphics.line(x+9,y+3,x+10,y+5)
love.graphics.line(x+10,y+5,x+12,y+6)
love.graphics.line(x+12,y+6,x+13,y+8)
love.graphics.line(x+13,y+8,x+13,y+10)
love.graphics.line(x+13,y+10,x+14,y+12)
love.graphics.line(x+14,y+12,x+15,y+14)
love.graphics.line(x+15,y+14,x+15,y+16)
end
function icon.line(x, y)
love.graphics.line(x+4,y+2, x+16,y+18)
end
function icon.manhattan(x, y)
love.graphics.line(x+4,y+20, x+4,y+2)
love.graphics.line(x+4,y+2, x+10,y+2)
love.graphics.line(x+10,y+2, x+10,y+10)
love.graphics.line(x+10,y+10, x+18,y+10)
end
function icon.polygon(x, y)
love.graphics.line(x+8,y+2, x+14,y+2)
love.graphics.line(x+14,y+2, x+18,y+10)
love.graphics.line(x+18,y+10, x+10,y+18)
love.graphics.line(x+10,y+18, x+4,y+12)
love.graphics.line(x+4,y+12, x+8,y+2)
end
function icon.circle(x, y)
love.graphics.circle('line', x+10,y+10, 8)
end
function draw_help_without_mouse_pressed(drawing)
love.graphics.setColor(0,0.5,0)
local y = drawing.y+10
love.graphics.print("Things you can do:", 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Press the mouse button to start drawing a "..current_shape(), 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Hover on a point and press 'ctrl+v' to start moving it,", 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("then press the mouse button to finish", 16+30+bullet_indent(),y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Hover on a point or shape and press 'ctrl+d' to delete it", 16+30,y, 0, Zoom)
y = y+15*Zoom
y = y+15*Zoom
if Current_mode ~= 'freehand' then
love.graphics.print("* Press 'ctrl+f' to switch to drawing freehand strokes", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'line' then
love.graphics.print("* Press 'ctrl+l' to switch to drawing lines", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'manhattan' then
love.graphics.print("* Press 'ctrl+m' to switch to drawing horizontal/vertical lines", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'circle' then
love.graphics.print("* Press 'ctrl+c' to switch to drawing circles/arcs", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'polygon' then
love.graphics.print("* Press 'ctrl+g' to switch to drawing polygons", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
love.graphics.print("* Press 'ctrl+=' or 'ctrl+-' to Zoom in or out", 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Press 'ctrl+0' to reset Zoom", 16+30,y, 0, Zoom)
y = y+15*Zoom
y = y+15*Zoom
love.graphics.print("Hit 'esc' now to hide this message", 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.setColor(0,0.5,0, 0.1)
love.graphics.rectangle('fill', 16,drawing.y, Drawing_width, math.max(pixels(drawing.h),y-drawing.y))
end
function draw_help_with_mouse_pressed(drawing)
love.graphics.setColor(0,0.5,0)
local y = drawing.y+10
love.graphics.print("You're currently drawing a "..current_shape(drawing.pending), 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print('Things you can do now:', 16+30,y, 0, Zoom)
y = y+15*Zoom
if Current_mode == 'freehand' then
love.graphics.print('* Release the mouse button to finish drawing the stroke', 16+30,y, 0, Zoom)
y = y+15*Zoom
elseif Current_mode == 'line' or Current_mode == 'manhattan' then
love.graphics.print('* Release the mouse button to finish drawing the line', 16+30,y, 0, Zoom)
y = y+15*Zoom
elseif Current_mode == 'circle' then
if drawing.pending.mode == 'circle' then
love.graphics.print('* Release the mouse button to finish drawing the circle', 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Press 'a' to draw just an arc of a circle", 16+30,y, 0, Zoom)
else
love.graphics.print('* Release the mouse button to finish drawing the arc', 16+30,y, 0, Zoom)
end
y = y+15*Zoom
elseif Current_mode == 'polygon' then
love.graphics.print('* Release the mouse button to finish drawing the polygon', 16+30,y, 0, Zoom)
y = y+15*Zoom
love.graphics.print("* Press 'p' to add a vertex to the polygon", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
love.graphics.print("* Press 'esc' then release the mouse button to cancel the current shape", 16+30,y, 0, Zoom)
y = y+15*Zoom
y = y+15*Zoom
if Current_mode ~= 'line' then
love.graphics.print("* Press 'l' to switch to drawing lines", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'manhattan' then
love.graphics.print("* Press 'm' to switch to drawing horizontal/vertical lines", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'circle' then
love.graphics.print("* Press 'c' to switch to drawing circles/arcs", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
if Current_mode ~= 'polygon' then
love.graphics.print("* Press 'g' to switch to drawing polygons", 16+30,y, 0, Zoom)
y = y+15*Zoom
end
love.graphics.setColor(0,0.5,0, 0.1)
love.graphics.rectangle('fill', 16,drawing.y, Drawing_width, math.max(pixels(drawing.h),y-drawing.y))
end
function current_shape(shape)
if Current_mode == 'freehand' then
return 'freehand stroke'
elseif Current_mode == 'line' then
return 'straight line'
elseif Current_mode == 'manhattan' then
return 'horizontal/vertical line'
elseif Current_mode == 'circle' and shape and shape.start_angle then
return 'arc'
else
return Current_mode
end
end
_bullet_indent = nil
function bullet_indent()
if _bullet_indent == nil then
local text = love.graphics.newText(love.graphics.getFont(), '* ')
_bullet_indent = text:getWidth()
end
return _bullet_indent
end
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