bugfix: manage screen_top and cursor when resizing

[?]

Jul 1, 2022, 5:30 PM

WOXIYUTL4NU7ACHQYXEXJDSXCRDLQ2X457KO6C7GEXFQZ43F3L7QC

Dependencies

[2] PX7DDEMO autosave slightly less aggressively
[3] DBNRULIJ record one more case I can't automatically detect
[*] BULPIBEG beginnings of a module for the text editor
[*] HOSPP2AN crisp font rendering
[*] OTIBCAUJ love2d scaffold
[*] 2RXZ3PGO beginning of a new approach to scroll+wrap
[*] K464QQR4 more defensive resize handling
[*] Z4XRNDTR find text
[*] OAHNWDYG .
[*] 2ENZW7TV select text using mouse drag
[*] BJ5X5O4A let's prevent the text cursor from ever getting on a drawing

Change contents

edit in text.lua at line 918

[6.3998]

[6.3998]

function Text.tweak_screen_top_and_cursor()
--? print('a', Selection1.line)
if Screen_top1.pos == 1 then return end
Text.populate_screen_line_starting_pos(Screen_top1.line)
local line = Lines[Screen_top1.line]
for i=2,#line.screen_line_starting_pos do
local pos = line.screen_line_starting_pos[i]
if pos == Screen_top1.pos then
break
end
if pos > Screen_top1.pos then
-- make sure screen top is at start of a screen line
local prev = line.screen_line_starting_pos[i-1]
if Screen_top1.pos - prev < pos - Screen_top1.pos then
Screen_top1.pos = prev
else
Screen_top1.pos = pos
end
break
end
end
-- make sure cursor is on screen
if Text.lt1(Cursor1, Screen_top1) then
Cursor1 = {line=Screen_top1.line, pos=Screen_top1.pos}
elseif Cursor1.line >= Screen_bottom1.line then
--? print('too low')
App.draw()
if Text.lt1(Screen_bottom1, Cursor1) then
--? print('tweak')
local line = Lines[Screen_bottom1.line]
Cursor1 = {line=Screen_bottom1.line, pos=Text.to_pos_on_line(line, App.screen.width-5, App.screen.height-5)}
end
end
end
edit in main.lua at line 55

[8.8975]

[8.9024]

--
-- Make sure these coordinates are never aliased, so that changing one causes
-- action at a distance.
edit in main.lua at line 193

[9.217]

[2.154]

Selection1 = {} -- no support for shift drag while we're resizing
Text.tweak_screen_top_and_cursor()
edit in main.lua at line 329

[10.2909]

[11.49]

--? print('press')
edit in main.lua at line 363

[10.2943]

[12.293]

--? print('release')
edit in Manual_tests.md at line 23

[3.301]

* Like any high-level language, it's easy to accidentally alias two non-scalar
variables. I wish there was a way to require copy when assigning.