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 Stroke_color = {r=0, g=0, b=0}
   5 Current_stroke_color = {r=0.7, g=0.7, b=0.7}  -- in process of being drawn
   6 Current_name_background_color = {r=1, g=0, b=0, a=0.1}  -- name currently being edited
   7 Focus_stroke_color = {r=1, g=0, b=0}  -- what mouse is hovering over
   8 Highlight_color = {r=0.7, g=0.7, b=0.9}  -- selected text
   9 Icon_color = {r=0.7, g=0.7, b=0.7}  -- color of current mode icon in drawings
  10 Help_color = {r=0, g=0.5, b=0}
  11 Help_background_color = {r=0, g=0.5, b=0, a=0.1}
  12
  13 Margin_top = 15
  14 Margin_left = 25
  15 Margin_right = 25
  16
  17 Drawing_padding_top = 10
  18 Drawing_padding_bottom = 10
  19 Drawing_padding_height = Drawing_padding_top + Drawing_padding_bottom
  20
  21 Same_point_distance = 4  -- pixel distance at which two points are considered the same
  22
  23 edit = {}
  24
  25 -- run in both tests and a real run
  26 function edit.initialize_state(top, left, right, font_height, line_height)  -- currently always draws to bottom of screen
  27   local result = {
  28     -- a line is either text or a drawing
  29     -- a text is a table with:
  30     --    mode = 'text',
  31     --    string data,
  32     -- a drawing is a table with:
  33     --    mode = 'drawing'
  34     --    a (y) coord in pixels (updated while painting screen),
  35     --    a (h)eight,
  36     --    an array of points, and
  37     --    an array of shapes
  38     -- a shape is a table containing:
  39     --    a mode
  40     --    an array points for mode 'freehand' (raw x,y coords; freehand drawings don't pollute the points array of a drawing)
  41     --    an array vertices for mode 'polygon', 'rectangle', 'square'
  42     --    p1, p2 for mode 'line'
  43     --    center, radius for mode 'circle'
  44     --    center, radius, start_angle, end_angle for mode 'arc'
  45     -- Unless otherwise specified, coord fields are normalized; a drawing is always 256 units wide
  46     -- The field names are carefully chosen so that switching modes in midstream
  47     -- remembers previously entered points where that makes sense.
  48     lines = {{mode='text', data=''}},  -- array of lines
  49
  50     -- Lines can be too long to fit on screen, in which case they _wrap_ into
  51     -- multiple _screen lines_.
  52
  53     -- rendering wrapped text lines needs some additional short-lived data per line:
  54     --   startpos, the index of data the line starts rendering from, can only be >1 for topmost line on screen
  55     --   starty, the y coord in pixels the line starts rendering from
  56     --   fragments: snippets of the line guaranteed to not straddle screen lines
  57     --   screen_line_starting_pos: optional array of grapheme indices if it wraps over more than one screen line
  58     line_cache = {},
  59
  60     -- Given wrapping, any potential location for the text cursor can be described in two ways:
  61     -- * schema 1: As a combination of line index and position within a line (in utf8 codepoint units)
  62     -- * schema 2: As a combination of line index, screen line index within the line, and a position within the screen line.
  63     --
  64     -- Most of the time we'll only persist positions in schema 1, translating to
  65     -- schema 2 when that's convenient.
  66     --
  67     -- Make sure these coordinates are never aliased, so that changing one causes
  68     -- action at a distance.
  69     screen_top1 = {line=1, pos=1},  -- position of start of screen line at top of screen
  70     cursor1 = {line=1, pos=1},  -- position of cursor
  71     screen_bottom1 = {line=1, pos=1},  -- position of start of screen line at bottom of screen
  72
  73     selection1 = {},
  74     -- some extra state to compute selection between mouse press and release
  75     old_cursor1 = nil,
  76     old_selection1 = nil,
  77     mousepress_shift = nil,
  78
  79     -- cursor coordinates in pixels
  80     cursor_x = 0,
  81     cursor_y = 0,
  82
  83     current_drawing_mode = 'line',
  84     previous_drawing_mode = nil,  -- extra state for some ephemeral modes like moving/deleting/naming points
  85
  86     font_height = font_height,
  87     line_height = line_height,
  88
  89     top = top,
  90     left = math.floor(left),
  91     right = math.floor(right),
  92     width = right-left,
  93
  94     filename = love.filesystem.getSourceBaseDirectory()..'/lines.txt',  -- '/' should work even on Windows
  95     next_save = nil,
  96
  97     -- undo
  98     history = {},
  99     next_history = 1,
 100
 101     -- search
 102     search_term = nil,
 103     search_backup = nil,  -- stuff to restore when cancelling search
 104   }
 105   return result
 106 end  -- App.initialize_state
 107
 108 function edit.check_locs(State)
 109   -- if State is inconsistent (i.e. file changed by some other program),
 110   --   throw away all cursor state entirely
 111   if edit.invalid1(State, State.screen_top1)
 112       or edit.invalid_cursor1(State)
 113       or not edit.cursor_on_text(State)
 114       or not Text.le1(State.screen_top1, State.cursor1) then
 115     State.screen_top1 = {line=1, pos=1}
 116     edit.put_cursor_on_first_text_line(State)
 117   end
 118 end
 119
 120 function edit.invalid1(State, loc1)
 121   if loc1.line > #State.lines then return true end
 122   local l = State.lines[loc1.line]
 123   if l.mode ~= 'text' then return false end  -- pos is irrelevant to validity for a drawing line
 124   return loc1.pos > #State.lines[loc1.line].data
 125 end
 126
 127 -- cursor loc in particular differs from other locs in one way:
 128 -- pos might occur just after end of line
 129 function edit.invalid_cursor1(State)
 130   local cursor1 = State.cursor1
 131   if cursor1.line > #State.lines then return true end
 132   local l = State.lines[cursor1.line]
 133   if l.mode ~= 'text' then return false end  -- pos is irrelevant to validity for a drawing line
 134   return cursor1.pos > #State.lines[cursor1.line].data + 1
 135 end
 136
 137 function edit.cursor_on_text(State)
 138   return State.cursor1.line <= #State.lines
 139       and State.lines[State.cursor1.line].mode == 'text'
 140 end
 141
 142 function edit.put_cursor_on_first_text_line(State)
 143   for i,line in ipairs(State.lines) do
 144     if line.mode == 'text' then
 145       State.cursor1 = {line=i, pos=1}
 146       break
 147     end
 148   end
 149 end
 150
 151 -- return y drawn until
 152 function edit.draw(State)
 153   State.button_handlers = {}
 154   App.color(Text_color)
 155   if #State.lines ~= #State.line_cache then
 156     print(('line_cache is out of date; %d when it should be %d'):format(#State.line_cache, #State.lines))
 157     assert(false)
 158   end
 159   if not Text.le1(State.screen_top1, State.cursor1) then
 160     print(State.screen_top1.line, State.screen_top1.pos, State.cursor1.line, State.cursor1.pos)
 161     assert(false)
 162   end
 163   State.cursor_x = nil
 164   State.cursor_y = nil
 165   local y = State.top
 166   local screen_bottom1 = {line=nil, pos=nil}
 167 --?   print('== draw')
 168   for line_index = State.screen_top1.line,#State.lines do
 169     local line = State.lines[line_index]
 170 --?     print('draw:', y, line_index, line)
 171     if y + State.line_height > App.screen.height then break end
 172     screen_bottom1.line = line_index
 173     if line.mode == 'text' then
 174 --?       print('text.draw', y, line_index)
 175       local startpos = 1
 176       if line_index == State.screen_top1.line then
 177         startpos = State.screen_top1.pos
 178       end
 179       if line.data == '' then
 180         -- button to insert new drawing
 181         button(State, 'draw', {x=State.left-Margin_left+4, y=y+4, w=12,h=12, color={1,1,0},
 182           icon = icon.insert_drawing,
 183           onpress1 = function()
 184                        Drawing.before = snapshot(State, line_index-1, line_index)
 185                        table.insert(State.lines, line_index, {mode='drawing', y=y, h=256/2, points={}, shapes={}, pending={}})
 186                        table.insert(State.line_cache, line_index, {})
 187                        if State.cursor1.line >= line_index then
 188                          State.cursor1.line = State.cursor1.line+1
 189                        end
 190                        schedule_save(State)
 191                        record_undo_event(State, {before=Drawing.before, after=snapshot(State, line_index-1, line_index+1)})
 192                      end,
 193         })
 194       end
 195       y, screen_bottom1.pos = Text.draw(State, line_index, y, startpos)
 196 --?       print('=> y', y)
 197     elseif line.mode == 'drawing' then
 198       y = y+Drawing_padding_top
 199       Drawing.draw(State, line_index, y)
 200       y = y + Drawing.pixels(line.h, State.width) + Drawing_padding_bottom
 201     else
 202       print(line.mode)
 203       assert(false)
 204     end
 205   end
 206   State.screen_bottom1 = screen_bottom1
 207   if State.search_term then
 208     Text.draw_search_bar(State)
 209   end
 210   return y
 211 end
 212
 213 function edit.update(State, dt)
 214   Drawing.update(State, dt)
 215   if State.next_save and State.next_save < Current_time then
 216     save_to_disk(State)
 217     State.next_save = nil
 218   end
 219 end
 220
 221 function schedule_save(State)
 222   if State.next_save == nil then
 223     State.next_save = Current_time + 3  -- short enough that you're likely to still remember what you did
 224   end
 225 end
 226
 227 function edit.quit(State)
 228   -- make sure to save before quitting
 229   if State.next_save then
 230     save_to_disk(State)
 231     -- give some time for the OS to flush everything to disk
 232     love.timer.sleep(0.1)
 233   end
 234 end
 235
 236 function edit.mouse_press(State, x,y, mouse_button)
 237   if State.search_term then return end
 238 --?   print_and_log(('edit.mouse_press: cursor at %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 239   if mouse_press_consumed_by_any_button_handler(State, x,y, mouse_button) then
 240     -- press on a button and it returned 'true' to short-circuit
 241     return
 242   end
 243
 244   if y < State.top then
 245     State.old_cursor1 = State.cursor1
 246     State.old_selection1 = State.selection1
 247     State.mousepress_shift = App.shift_down()
 248     State.selection1 = {
 249         line=State.screen_top1.line,
 250         pos=State.screen_top1.pos,
 251     }
 252     return
 253   end
 254
 255   for line_index,line in ipairs(State.lines) do
 256     if line.mode == 'text' then
 257       if Text.in_line(State, line_index, x,y) then
 258         -- delicate dance between cursor, selection and old cursor/selection
 259         -- scenarios:
 260         --  regular press+release: sets cursor, clears selection
 261         --  shift press+release:
 262         --    sets selection to old cursor if not set otherwise leaves it untouched
 263         --    sets cursor
 264         --  press and hold to start a selection: sets selection on press, cursor on release
 265         --  press and hold, then press shift: ignore shift
 266         --    i.e. mouse_release should never look at shift state
 267 --?         print_and_log(('edit.mouse_press: in line %d'):format(line_index))
 268         State.old_cursor1 = State.cursor1
 269         State.old_selection1 = State.selection1
 270         State.mousepress_shift = App.shift_down()
 271         State.selection1 = {
 272             line=line_index,
 273             pos=Text.to_pos_on_line(State, line_index, x, y),
 274         }
 275         return
 276       end
 277     elseif line.mode == 'drawing' then
 278       local line_cache = State.line_cache[line_index]
 279       if Drawing.in_drawing(line, line_cache, x, y, State.left,State.right) then
 280         State.lines.current_drawing_index = line_index
 281         State.lines.current_drawing = line
 282         Drawing.before = snapshot(State, line_index)
 283         Drawing.mouse_press(State, line_index, x,y, mouse_button)
 284         return
 285       end
 286     end
 287   end
 288
 289   -- still here? click is below all screen lines
 290   State.old_cursor1 = State.cursor1
 291   State.old_selection1 = State.selection1
 292   State.mousepress_shift = App.shift_down()
 293   State.selection1 = {
 294       line=State.screen_bottom1.line,
 295       pos=Text.pos_at_end_of_screen_line(State, State.screen_bottom1),
 296   }
 297 end
 298
 299 function edit.mouse_release(State, x,y, mouse_button)
 300   if State.search_term then return end
 301 --?   print_and_log(('edit.mouse_release: cursor at %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 302   if State.lines.current_drawing then
 303     Drawing.mouse_release(State, x,y, mouse_button)
 304     schedule_save(State)
 305     if Drawing.before then
 306       record_undo_event(State, {before=Drawing.before, after=snapshot(State, State.lines.current_drawing_index)})
 307       Drawing.before = nil
 308     end
 309   else
 310 --?     print_and_log('edit.mouse_release: no current drawing')
 311     for line_index,line in ipairs(State.lines) do
 312       if line.mode == 'text' then
 313         if Text.in_line(State, line_index, x,y) then
 314 --?           print_and_log(('edit.mouse_release: in line %d'):format(line_index))
 315           State.cursor1 = {
 316               line=line_index,
 317               pos=Text.to_pos_on_line(State, line_index, x, y),
 318           }
 319 --?           print_and_log(('edit.mouse_release: cursor now %d,%d'):format(State.cursor1.line, State.cursor1.pos))
 320           if State.mousepress_shift then
 321             if State.old_selection1.line == nil then
 322               State.selection1 = State.old_cursor1
 323             else
 324               State.selection1 = State.old_selection1
 325             end
 326           end
 327           State.old_cursor1, State.old_selection1, State.mousepress_shift = nil
 328           if eq(State.cursor1, State.selection1) then
 329             State.selection1 = {}
 330           end
 331           break
 332         end
 333       end
 334     end
 335 --?     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))
 336   end
 337 end
 338
 339 function edit.mouse_wheel_move(State, dx,dy)
 340   if dy > 0 then
 341     State.cursor1 = {line=State.screen_top1.line, pos=State.screen_top1.pos}
 342     for i=1,math.floor(dy) do
 343       Text.up(State)
 344     end
 345   elseif dy < 0 then
 346     State.cursor1 = {line=State.screen_bottom1.line, pos=State.screen_bottom1.pos}
 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.setClipboardText(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.setClipboardText(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.getClipboardText()
 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