source_edit.lua

   1 -- some constants people might like to tweak
   2 Text_color = {r=0, g=0, b=0}
   3 Cursor_color = {r=1, g=0, b=0}
   4 Hyperlink_decoration_color = {r=0.4, g=0.4, b=1}
   5 Stroke_color = {r=0, g=0, b=0}
   6 Current_stroke_color = {r=0.7, g=0.7, b=0.7}  -- in process of being drawn
   7 Current_name_background_color = {r=1, g=0, b=0, a=0.1}  -- name currently being edited
   8 Focus_stroke_color = {r=1, g=0, b=0}  -- what mouse is hovering over
   9 Highlight_color = {r=0.7, g=0.7, b=0.9}  -- selected text
  10 Line_number_color = {r=0.6, g=0.6, b=0.6}
  11 Icon_color = {r=0.7, g=0.7, b=0.7}  -- color of current mode icon in drawings
  12 Help_color = {r=0, g=0.5, b=0}
  13 Help_background_color = {r=0, g=0.5, b=0, a=0.1}
  14
  15 Margin_top = 15
  16 Margin_left = 25
  17 Margin_right = 25
  18
  19 Drawing_padding_top = 10
  20 Drawing_padding_bottom = 10
  21 Drawing_padding_height = Drawing_padding_top + Drawing_padding_bottom
  22
  23 Same_point_distance = 4  -- pixel distance at which two points are considered the same
  24
  25 edit = {}
  26
  27 -- run in both tests and a real run
  28 function edit.initialize_state(top, left, right, font_height, line_height)  -- currently always draws to bottom of screen
  29   local result = {
  30     -- a line is either text or a drawing
  31     -- a text is a table with:
  32     --    mode = 'text',
  33     --    string data,
  34     -- a drawing is a table with:
  35     --    mode = 'drawing'
  36     --    a (y) coord in pixels (updated while painting screen),
  37     --    a (h)eight,
  38     --    an array of points, and
  39     --    an array of shapes
  40     -- a shape is a table containing:
  41     --    a mode
  42     --    an array points for mode 'freehand' (raw x,y coords; freehand drawings don't pollute the points array of a drawing)
  43     --    an array vertices for mode 'polygon', 'rectangle', 'square'
  44     --    p1, p2 for mode 'line'
  45     --    center, radius for mode 'circle'
  46     --    center, radius, start_angle, end_angle for mode 'arc'
  47     -- Unless otherwise specified, coord fields are normalized; a drawing is always 256 units wide
  48     -- The field names are carefully chosen so that switching modes in midstream
  49     -- remembers previously entered points where that makes sense.
  50     lines = {{mode='text', data=''}},  -- array of lines
  51
  52     -- Lines can be too long to fit on screen, in which case they _wrap_ into
  53     -- multiple _screen lines_.
  54
  55     -- rendering wrapped text lines needs some additional short-lived data per line:
  56     --   startpos, the index of data the line starts rendering from, can only be >1 for topmost line on screen
  57     --   starty, the y coord in pixels the line starts rendering from
  58     --   fragments: snippets of the line guaranteed to not straddle screen lines
  59     --   screen_line_starting_pos: optional array of grapheme indices if it wraps over more than one screen line
  60     line_cache = {},
  61
  62     -- Given wrapping, any potential location for the text cursor can be described in two ways:
  63     -- * schema 1: As a combination of line index and position within a line (in utf8 codepoint units)
  64     -- * schema 2: As a combination of line index, screen line index within the line, and a position within the screen line.
  65     --
  66     -- Most of the time we'll only persist positions in schema 1, translating to
  67     -- schema 2 when that's convenient.
  68     --
  69     -- Make sure these coordinates are never aliased, so that changing one causes
  70     -- action at a distance.
  71     screen_top1 = {line=1, pos=1},  -- position of start of screen line at top of screen
  72     cursor1 = {line=1, pos=1},  -- position of cursor
  73     screen_bottom1 = {line=1, pos=1},  -- position of start of screen line at bottom of screen
  74
  75     selection1 = {},
  76     -- some extra state to compute selection between mouse press and release
  77     old_cursor1 = nil,
  78     old_selection1 = nil,
  79     mousepress_shift = nil,
  80
  81     -- cursor coordinates in pixels
  82     cursor_x = 0,
  83     cursor_y = 0,
  84
  85     current_drawing_mode = 'line',
  86     previous_drawing_mode = nil,  -- extra state for some ephemeral modes like moving/deleting/naming points
  87
  88     font_height = font_height,
  89     line_height = line_height,
  90
  91     top = top,
  92     left = math.floor(left),  -- left margin for text; line numbers go to the left of this
  93     right = math.floor(right),
  94     width = right-left,
  95
  96     filename = love.filesystem.getSourceBaseDirectory()..'/lines.txt',  -- '/' should work even on Windows
  97     next_save = nil,
  98
  99     -- undo
 100     history = {},
 101     next_history = 1,
 102
 103     -- search
 104     search_term = nil,
 105     search_backup = nil,  -- stuff to restore when cancelling search
 106   }
 107   return result
 108 end  -- App.initialize_state
 109
 110 function edit.check_locs(State)
 111   -- if State is inconsistent (i.e. file changed by some other program),
 112   --   throw away all cursor state entirely
 113   if edit.invalid1(State, State.screen_top1)
 114       or edit.invalid1(State, State.cursor1)
 115       or not edit.cursor_on_text(State)
 116       or not Text.le1(State.screen_top1, State.cursor1) then
 117     State.screen_top1 = {line=1, pos=1}
 118     edit.put_cursor_on_next_text_line(State)
 119   end
 120 end
 121
 122 function edit.invalid1(State, loc1)
 123   if loc1.line > #State.lines then return true end
 124   local l = State.lines[loc1.line]
 125   if l.mode ~= 'text' then return false end  -- pos is irrelevant to validity for a drawing line
 126   return loc1.pos > #State.lines[loc1.line].data
 127 end
 128
 129 function edit.cursor_on_text(State)
 130   return State.cursor1.line <= #State.lines
 131       and State.lines[State.cursor1.line].mode == 'text'
 132 end
 133
 134 function edit.put_cursor_on_next_text_line(State)
 135   while true do
 136   if State.cursor1.line >= #State.lines then
 137     break
 138   end
 139   if State.lines[State.cursor1.line].mode == 'text' then
 140     break
 141   end
 142   State.cursor1.line = State.cursor1.line+1
 143   State.cursor1.pos = 1
 144   end
 145 end
 146
 147 function edit.draw(State, hide_cursor, show_line_numbers)
 148   State.button_handlers = {}
 149   App.color(Text_color)
 150   if #State.lines ~= #State.line_cache then
 151     print(('line_cache is out of date; %d when it should be %d'):format(#State.line_cache, #State.lines))
 152     assert(false)
 153   end
 154   if not Text.le1(State.screen_top1, State.cursor1) then
 155     print(State.screen_top1.line, State.screen_top1.pos, State.cursor1.line, State.cursor1.pos)
 156     assert(false)
 157   end
 158   State.cursor_x = nil
 159   State.cursor_y = nil
 160   local y = State.top
 161   local screen_bottom1 = {line=nil, pos=nil}
 162 --?   print('== draw')
 163   for line_index = State.screen_top1.line,#State.lines do
 164     local line = State.lines[line_index]
 165 --?     print('draw:', y, line_index, line)
 166     if y + State.line_height > App.screen.height then break end
 167     screen_bottom1.line = line_index
 168     if line.mode == 'text' then
 169 --?       print('text.draw', y, line_index)
 170       local startpos = 1
 171       if line_index == State.screen_top1.line then
 172         startpos = State.screen_top1.pos
 173       end
 174       if line.data == '' then
 175         -- button to insert new drawing
 176         local buttonx = State.left-Margin_left+4
 177         if show_line_numbers then
 178           buttonx = 4  -- HACK: position draw buttons at a fixed x on screen
 179         end
 180         button(State, 'draw', {x=buttonx, y=y+4, w=12,h=12, color={1,1,0},
 181           icon = icon.insert_drawing,
 182           onpress1 = function()
 183                        Drawing.before = snapshot(State, line_index-1, line_index)
 184                        table.insert(State.lines, line_index, {mode='drawing', y=y, h=256/2, points={}, shapes={}, pending={}})
 185                        table.insert(State.line_cache, line_index, {})
 186                        if State.cursor1.line >= line_index then
 187                          State.cursor1.line = State.cursor1.line+1
 188                        end
 189                        schedule_save(State)
 190                        record_undo_event(State, {before=Drawing.before, after=snapshot(State, line_index-1, line_index+1)})
 191                      end,
 192         })
 193       end
 194       y, screen_bottom1.pos = Text.draw(State, line_index, y, startpos, hide_cursor, show_line_numbers)
 195 --?       print('=> y', y)
 196     elseif line.mode == 'drawing' then
 197       y = y+Drawing_padding_top
 198       Drawing.draw(State, line_index, y)
 199       y = y + Drawing.pixels(line.h, State.width) + Drawing_padding_bottom
 200     else
 201       print(line.mode)
 202       assert(false)
 203     end
 204   end
 205   State.screen_bottom1 = screen_bottom1
 206   if State.search_term then
 207     Text.draw_search_bar(State)
 208   end
 209 end
 210
 211 function edit.update(State, dt)
 212   Drawing.update(State, dt)
 213   if State.next_save and State.next_save < Current_time then
 214     save_to_disk(State)
 215     State.next_save = nil
 216   end
 217 end
 218
 219 function schedule_save(State)
 220   if State.next_save == nil then
 221     State.next_save = Current_time + 3  -- short enough that you're likely to still remember what you did
 222   end
 223 end
 224
 225 function edit.quit(State)
 226   -- make sure to save before quitting
 227   if State.next_save then
 228     save_to_disk(State)
 229     -- give some time for the OS to flush everything to disk
 230     love.timer.sleep(0.1)
 231   end
 232 end
 233
 234 function edit.mouse_press(State, x,y, mouse_button)
 235   if State.search_term then return end
 236 --?   print_and_log(('edit.mouse_press: cursor at %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 237   if mouse_press_consumed_by_any_button_handler(State, x,y, mouse_button) then
 238     -- press on a button and it returned 'true' to short-circuit
 239     return
 240   end
 241
 242   if y < State.top then
 243     State.old_cursor1 = State.cursor1
 244     State.old_selection1 = State.selection1
 245     State.mousepress_shift = App.shift_down()
 246     State.selection1 = {
 247         line=State.screen_top1.line,
 248         pos=State.screen_top1.pos,
 249     }
 250     return
 251   end
 252
 253   for line_index,line in ipairs(State.lines) do
 254     if line.mode == 'text' then
 255       if Text.in_line(State, line_index, x,y) then
 256         -- delicate dance between cursor, selection and old cursor/selection
 257         -- scenarios:
 258         --  regular press+release: sets cursor, clears selection
 259         --  shift press+release:
 260         --    sets selection to old cursor if not set otherwise leaves it untouched
 261         --    sets cursor
 262         --  press and hold to start a selection: sets selection on press, cursor on release
 263         --  press and hold, then press shift: ignore shift
 264         --    i.e. mouse_release should never look at shift state
 265 --?         print_and_log(('edit.mouse_press: in line %d'):format(line_index))
 266         State.old_cursor1 = State.cursor1
 267         State.old_selection1 = State.selection1
 268         State.mousepress_shift = App.shift_down()
 269         State.selection1 = {
 270             line=line_index,
 271             pos=Text.to_pos_on_line(State, line_index, x, y),
 272         }
 273         return
 274       end
 275     elseif line.mode == 'drawing' then
 276       local line_cache = State.line_cache[line_index]
 277       if Drawing.in_drawing(line, line_cache, x, y, State.left,State.right) then
 278         State.lines.current_drawing_index = line_index
 279         State.lines.current_drawing = line
 280         Drawing.before = snapshot(State, line_index)
 281         Drawing.mouse_press(State, line_index, x,y, mouse_button)
 282         return
 283       end
 284     end
 285   end
 286
 287   -- still here? click is below all screen lines
 288   State.old_cursor1 = State.cursor1
 289   State.old_selection1 = State.selection1
 290   State.mousepress_shift = App.shift_down()
 291   State.selection1 = {
 292       line=State.screen_bottom1.line,
 293       pos=Text.pos_at_end_of_screen_line(State, State.screen_bottom1),
 294   }
 295 end
 296
 297 function edit.mouse_release(State, x,y, mouse_button)
 298   if State.search_term then return end
 299 --?   print_and_log(('edit.mouse_release: cursor at %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 300   if State.lines.current_drawing then
 301     Drawing.mouse_release(State, x,y, mouse_button)
 302     schedule_save(State)
 303     if Drawing.before then
 304       record_undo_event(State, {before=Drawing.before, after=snapshot(State, State.lines.current_drawing_index)})
 305       Drawing.before = nil
 306     end
 307   else
 308 --?     print_and_log('edit.mouse_release: no current drawing')
 309     for line_index,line in ipairs(State.lines) do
 310       if line.mode == 'text' then
 311         if Text.in_line(State, line_index, x,y) then
 312 --?           print_and_log(('edit.mouse_release: in line %d'):format(line_index))
 313           State.cursor1 = {
 314               line=line_index,
 315               pos=Text.to_pos_on_line(State, line_index, x, y),
 316           }
 317 --?           print_and_log(('edit.mouse_release: cursor now %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 318           if State.mousepress_shift then
 319             if State.old_selection1.line == nil then
 320               State.selection1 = State.old_cursor1
 321             else
 322               State.selection1 = State.old_selection1
 323             end
 324           end
 325           State.old_cursor1, State.old_selection1, State.mousepress_shift = nil
 326           if eq(State.cursor1, State.selection1) then
 327             State.selection1 = {}
 328           end
 329           break
 330         end
 331       end
 332     end
 333 --?     print_and_log(('edit.mouse_release: finally selection %s,%s cursor %d,%d'):format(tostring(State.selection1.line), tostring(State.selection1.pos), State.cursor1.line, State.cursor1.pos))
 334   end
 335 end
 336
 337 function edit.mouse_wheel_move(State, dx,dy)
 338   if dy > 0 then
 339     State.cursor1 = {line=State.screen_top1.line, pos=State.screen_top1.pos}
 340     edit.put_cursor_on_next_text_line(State)
 341     for i=1,math.floor(dy) do
 342       Text.up(State)
 343     end
 344   elseif dy < 0 then
 345     State.cursor1 = {line=State.screen_bottom1.line, pos=State.screen_bottom1.pos}
 346     edit.put_cursor_on_next_text_line(State)
 347     for i=1,math.floor(-dy) do
 348       Text.down(State)
 349     end
 350   end
 351 end
 352
 353 function edit.text_input(State, t)
 354 --?   print('text input', t)
 355   if State.search_term then
 356     State.search_term = State.search_term..t
 357     Text.search_next(State)
 358   elseif State.lines.current_drawing and State.current_drawing_mode == 'name' then
 359     local before = snapshot(State, State.lines.current_drawing_index)
 360     local drawing = State.lines.current_drawing
 361     local p = drawing.points[drawing.pending.target_point]
 362     p.name = p.name..t
 363     record_undo_event(State, {before=before, after=snapshot(State, State.lines.current_drawing_index)})
 364   else
 365     local drawing_index, drawing = Drawing.current_drawing(State)
 366     if drawing_index == nil then
 367       for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 368       Text.text_input(State, t)
 369     end
 370   end
 371   schedule_save(State)
 372 end
 373
 374 function edit.keychord_press(State, chord, key)
 375   if State.selection1.line and
 376       not State.lines.current_drawing and
 377       -- printable character created using shift key => delete selection
 378       -- (we're not creating any ctrl-shift- or alt-shift- combinations using regular/printable keys)
 379       (not App.shift_down() or utf8.len(key) == 1) and
 380       chord ~= 'C-a' and chord ~= 'C-c' and chord ~= 'C-x' and chord ~= 'backspace' and chord ~= 'delete' and chord ~= 'C-z' and chord ~= 'C-y' and not App.is_cursor_movement(chord) then
 381     Text.delete_selection(State, State.left, State.right)
 382   end
 383   if State.search_term then
 384     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 385     if chord == 'escape' then
 386       State.search_term = nil
 387       State.cursor1 = State.search_backup.cursor
 388       State.screen_top1 = State.search_backup.screen_top
 389       State.search_backup = nil
 390       Text.redraw_all(State)  -- if we're scrolling, reclaim all fragments to avoid memory leaks
 391     elseif chord == 'return' then
 392       State.search_term = nil
 393       State.search_backup = nil
 394     elseif chord == 'backspace' then
 395       local len = utf8.len(State.search_term)
 396       local byte_offset = Text.offset(State.search_term, len)
 397       State.search_term = string.sub(State.search_term, 1, byte_offset-1)
 398     elseif chord == 'down' then
 399       State.cursor1.pos = State.cursor1.pos+1
 400       Text.search_next(State)
 401     elseif chord == 'up' then
 402       Text.search_previous(State)
 403     end
 404     return
 405   elseif chord == 'C-f' then
 406     State.search_term = ''
 407     State.search_backup = {
 408       cursor={line=State.cursor1.line, pos=State.cursor1.pos},
 409       screen_top={line=State.screen_top1.line, pos=State.screen_top1.pos},
 410     }
 411   -- zoom
 412   elseif chord == 'C-=' then
 413     edit.update_font_settings(State, State.font_height+2)
 414     Text.redraw_all(State)
 415   elseif chord == 'C--' then
 416     if State.font_height > 2 then
 417       edit.update_font_settings(State, State.font_height-2)
 418       Text.redraw_all(State)
 419     end
 420   elseif chord == 'C-0' then
 421     edit.update_font_settings(State, 20)
 422     Text.redraw_all(State)
 423   -- undo
 424   elseif chord == 'C-z' then
 425     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 426     local event = undo_event(State)
 427     if event then
 428       local src = event.before
 429       State.screen_top1 = deepcopy(src.screen_top)
 430       State.cursor1 = deepcopy(src.cursor)
 431       State.selection1 = deepcopy(src.selection)
 432       patch(State.lines, event.after, event.before)
 433       patch_placeholders(State.line_cache, event.after, event.before)
 434       -- invalidate various cached bits of lines
 435       State.lines.current_drawing = nil
 436       -- if we're scrolling, reclaim all fragments to avoid memory leaks
 437       Text.redraw_all(State)
 438       schedule_save(State)
 439     end
 440   elseif chord == 'C-y' then
 441     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 442     local event = redo_event(State)
 443     if event then
 444       local src = event.after
 445       State.screen_top1 = deepcopy(src.screen_top)
 446       State.cursor1 = deepcopy(src.cursor)
 447       State.selection1 = deepcopy(src.selection)
 448       patch(State.lines, event.before, event.after)
 449       -- invalidate various cached bits of lines
 450       State.lines.current_drawing = nil
 451       -- if we're scrolling, reclaim all fragments to avoid memory leaks
 452       Text.redraw_all(State)
 453       schedule_save(State)
 454     end
 455   -- clipboard
 456   elseif chord == 'C-a' then
 457     State.selection1 = {line=1, pos=1}
 458     State.cursor1 = {line=#State.lines, pos=utf8.len(State.lines[#State.lines].data)+1}
 459   elseif chord == 'C-c' then
 460     local s = Text.selection(State)
 461     if s then
 462       App.set_clipboard(s)
 463     end
 464   elseif chord == 'C-x' then
 465     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 466     local s = Text.cut_selection(State, State.left, State.right)
 467     if s then
 468       App.set_clipboard(s)
 469     end
 470     schedule_save(State)
 471   elseif chord == 'C-v' then
 472     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 473     -- We don't have a good sense of when to scroll, so we'll be conservative
 474     -- and sometimes scroll when we didn't quite need to.
 475     local before_line = State.cursor1.line
 476     local before = snapshot(State, before_line)
 477     local clipboard_data = App.get_clipboard()
 478     for _,code in utf8.codes(clipboard_data) do
 479       local c = utf8.char(code)
 480       if c == '\n' then
 481         Text.insert_return(State)
 482       else
 483         Text.insert_at_cursor(State, c)
 484       end
 485     end
 486     if Text.cursor_out_of_screen(State) then
 487       Text.snap_cursor_to_bottom_of_screen(State, State.left, State.right)
 488     end
 489     schedule_save(State)
 490     record_undo_event(State, {before=before, after=snapshot(State, before_line, State.cursor1.line)})
 491   -- dispatch to drawing or text
 492   elseif App.mouse_down(1) or chord:sub(1,2) == 'C-' then
 493     -- DON'T reset line_cache.starty here
 494     local drawing_index, drawing = Drawing.current_drawing(State)
 495     if drawing_index then
 496       local before = snapshot(State, drawing_index)
 497       Drawing.keychord_press(State, chord)
 498       record_undo_event(State, {before=before, after=snapshot(State, drawing_index)})
 499       schedule_save(State)
 500     end
 501   elseif chord == 'escape' and not App.mouse_down(1) then
 502     for _,line in ipairs(State.lines) do
 503       if line.mode == 'drawing' then
 504         line.show_help = false
 505       end
 506     end
 507   elseif State.lines.current_drawing and State.current_drawing_mode == 'name' then
 508     if chord == 'return' then
 509       State.current_drawing_mode = State.previous_drawing_mode
 510       State.previous_drawing_mode = nil
 511     else
 512       local before = snapshot(State, State.lines.current_drawing_index)
 513       local drawing = State.lines.current_drawing
 514       local p = drawing.points[drawing.pending.target_point]
 515       if chord == 'escape' then
 516         p.name = nil
 517         record_undo_event(State, {before=before, after=snapshot(State, State.lines.current_drawing_index)})
 518       elseif chord == 'backspace' then
 519         local len = utf8.len(p.name)
 520         if len > 0 then
 521           local byte_offset = Text.offset(p.name, len-1)
 522           if len == 1 then byte_offset = 0 end
 523           p.name = string.sub(p.name, 1, byte_offset)
 524           record_undo_event(State, {before=before, after=snapshot(State, State.lines.current_drawing_index)})
 525         end
 526       end
 527     end
 528     schedule_save(State)
 529   else
 530     for _,line_cache in ipairs(State.line_cache) do line_cache.starty = nil end  -- just in case we scroll
 531     Text.keychord_press(State, chord)
 532   end
 533 end
 534
 535 function edit.key_release(State, key, scancode)
 536 end
 537
 538 function edit.update_font_settings(State, font_height)
 539   State.font_height = font_height
 540   love.graphics.setFont(love.graphics.newFont(State.font_height))
 541   State.line_height = math.floor(font_height*1.3)
 542 end
 543
 544 --== some methods for tests
 545
 546 -- Insulate tests from some key globals so I don't have to change the vast
 547 -- majority of tests when they're modified for the real app.
 548 Test_margin_left = 25
 549 Test_margin_right = 0
 550
 551 function edit.initialize_test_state()
 552   -- if you change these values, tests will start failing
 553   return edit.initialize_state(
 554       15,  -- top margin
 555       Test_margin_left,
 556       App.screen.width - Test_margin_right,
 557       14,  -- font height assuming default LÖVE font
 558       15)  -- line height
 559 end
 560
 561 -- all text_input events are also keypresses
 562 -- TODO: handle chords of multiple keys
 563 function edit.run_after_text_input(State, t)
 564   edit.keychord_press(State, t)
 565   edit.text_input(State, t)
 566   edit.key_release(State, t)
 567   App.screen.contents = {}
 568   edit.update(State, 0)
 569   edit.draw(State)
 570 end
 571
 572 -- not all keys are text_input
 573 function edit.run_after_keychord(State, chord)
 574   edit.keychord_press(State, chord)
 575   edit.key_release(State, chord)
 576   App.screen.contents = {}
 577   edit.update(State, 0)
 578   edit.draw(State)
 579 end
 580
 581 function edit.run_after_mouse_click(State, x,y, mouse_button)
 582   App.fake_mouse_press(x,y, mouse_button)
 583   edit.mouse_press(State, x,y, mouse_button)
 584   App.fake_mouse_release(x,y, mouse_button)
 585   edit.mouse_release(State, x,y, mouse_button)
 586   App.screen.contents = {}
 587   edit.update(State, 0)
 588   edit.draw(State)
 589 end
 590
 591 function edit.run_after_mouse_press(State, x,y, mouse_button)
 592   App.fake_mouse_press(x,y, mouse_button)
 593   edit.mouse_press(State, x,y, mouse_button)
 594   App.screen.contents = {}
 595   edit.update(State, 0)
 596   edit.draw(State)
 597 end
 598
 599 function edit.run_after_mouse_release(State, x,y, mouse_button)
 600   App.fake_mouse_release(x,y, mouse_button)
 601   edit.mouse_release(State, x,y, mouse_button)
 602   App.screen.contents = {}
 603   edit.update(State, 0)
 604   edit.draw(State)
 605 end