-- text editor, particularly text drawing, horizontal wrap, vertical scrolling
Text = {}
local utf8 = require 'utf8'
require 'search'
require 'select'
require 'undo'
require 'text_tests'
-- return values:
-- y coordinate drawn until in px
-- position of start of final screen line drawn
function Text.draw(line, line_width, line_index)
--? print('text.draw')
love.graphics.setColor(0,0,0)
-- wrap long lines
local x = 25
local y = line.y
local pos = 1
local screen_line_starting_pos = 1
if line.fragments == nil then
Text.compute_fragments(line, line_width)
end
if line.screen_line_starting_pos == nil then
Text.populate_screen_line_starting_pos(line_index)
end
--? print('--')
for _, f in ipairs(line.fragments) do
local frag, frag_text = f.data, f.text
-- render fragment
local frag_width = App.width(frag_text)
local frag_len = utf8.len(frag)
--? local s=tostring
--? print('('..s(x)..','..s(y)..') '..frag..'('..s(frag_width)..' vs '..s(line_width)..') '..s(line_index)..' vs '..s(Screen_top1.line)..'; '..s(pos)..' vs '..s(Screen_top1.pos)..'; bottom: '..s(Screen_bottom1.line)..'/'..s(Screen_bottom1.pos))
if x + frag_width > line_width then
assert(x > 25) -- no overfull lines
-- update y only after drawing the first screen line of screen top
if Text.lt1(Screen_top1, {line=line_index, pos=pos}) then
y = y + Line_height
if y + Line_height > App.screen.height then
--? print('b', y, App.screen.height, '=>', screen_line_starting_pos)
return y, screen_line_starting_pos
end
screen_line_starting_pos = pos
--? print('text: new screen line', y, App.screen.height, screen_line_starting_pos)
end
x = 25
end
--? print('checking to draw', pos, Screen_top1.pos)
-- don't draw text above screen top
if Text.le1(Screen_top1, {line=line_index, pos=pos}) then
if Selection1.line then
local lo, hi = Text.clip_selection(line_index, pos, pos+frag_len)
Text.draw_highlight(line, x,y, pos, lo,hi)
end
--? print('drawing '..frag)
App.screen.draw(frag_text, x,y)
end
-- render cursor if necessary
if line_index == Cursor1.line then
if pos <= Cursor1.pos and pos + frag_len > Cursor1.pos then
if Search_term then
if Lines[Cursor1.line].data:sub(Cursor1.pos, Cursor1.pos+utf8.len(Search_term)-1) == Search_term then
local lo_px = Text.draw_highlight(line, x,y, pos, Cursor1.pos, Cursor1.pos+utf8.len(Search_term))
love.graphics.setColor(0,0,0)
love.graphics.print(Search_term, x+lo_px,y)
end
else
Text.draw_cursor(x+Text.x(frag, Cursor1.pos-pos+1), y)
end
end
end
x = x + frag_width
pos = pos + frag_len
end
if Search_term == nil then
if line_index == Cursor1.line and Cursor1.pos == pos then
Text.draw_cursor(x, y)
end
end
return y, screen_line_starting_pos
end
-- manual tests:
-- draw with small line_width of 100
function Text.draw_cursor(x, y)
-- blink every 0.5s
if math.floor(Cursor_time*2)%2 == 0 then
love.graphics.setColor(1,0,0)
love.graphics.rectangle('fill', x,y, 3,Line_height)
love.graphics.setColor(0,0,0)
end
Cursor_x = x
Cursor_y = y+Line_height
end
function Text.compute_fragments(line, line_width)
--? print('compute_fragments', line_width)
line.fragments = {}
local x = 25
-- try to wrap at word boundaries
for frag in line.data:gmatch('%S*%s*') do
local frag_text = App.newText(love.graphics.getFont(), frag)
local frag_width = App.width(frag_text)
--? print('x: '..tostring(x)..'; '..tostring(line_width-x)..'px to go')
--? print('frag: ^'..frag..'$ is '..tostring(frag_width)..'px wide')
if x + frag_width > line_width then
while x + frag_width > line_width do
--? print(x, frag, frag_width, line_width)
if x < 0.8*line_width then
--? print(frag, x, frag_width, line_width)
-- long word; chop it at some letter
-- We're not going to reimplement TeX here.
local b = Text.nearest_pos_less_than(frag, line_width - x)
assert(b > 0) -- avoid infinite loop when window is too narrow
--? print('space for '..tostring(b)..' graphemes')
local frag1 = string.sub(frag, 1, b)
local frag1_text = App.newText(love.graphics.getFont(), frag1)
local frag1_width = App.width(frag1_text)
--? print(frag, x, frag1_width, line_width)
assert(x + frag1_width <= line_width)
--? print('inserting '..frag1..' of width '..tostring(frag1_width)..'px')
table.insert(line.fragments, {data=frag1, text=frag1_text})
frag = string.sub(frag, b+1)
frag_text = App.newText(love.graphics.getFont(), frag)
frag_width = App.width(frag_text)
end
x = 25 -- new line
end
end
if #frag > 0 then
--? print('inserting '..frag..' of width '..tostring(frag_width)..'px')
table.insert(line.fragments, {data=frag, text=frag_text})
end
x = x + frag_width
end
end
function Text.textinput(t)
if love.mouse.isDown('1') then return end
if App.ctrl_down() or App.alt_down() or App.cmd_down() then return end
if Selection1.line then
Text.delete_selection()
end
local before = snapshot(Cursor1.line)
--? print(Screen_top1.line, Screen_top1.pos, Cursor1.line, Cursor1.pos, Screen_bottom1.line, Screen_bottom1.pos)
Text.insert_at_cursor(t)
if Cursor_y >= App.screen.height - Line_height then
Text.populate_screen_line_starting_pos(Cursor1.line)
Text.snap_cursor_to_bottom_of_screen()
--? print('=>', Screen_top1.line, Screen_top1.pos, Cursor1.line, Cursor1.pos, Screen_bottom1.line, Screen_bottom1.pos)
end
record_undo_event({before=before, after=snapshot(Cursor1.line)})
end
function Text.insert_at_cursor(t)
local byte_offset
if Cursor1.pos > 1 then
byte_offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
else
byte_offset = 1
end
if byte_offset == nil then
print(Cursor1.line, Cursor1.pos, byte_offset, Lines[Cursor1.line].data)
assert(false)
end
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_offset-1)..t..string.sub(Lines[Cursor1.line].data, byte_offset)
Lines[Cursor1.line].fragments = nil
Lines[Cursor1.line].screen_line_starting_pos = nil
Cursor1.pos = Cursor1.pos+1
end
-- Don't handle any keys here that would trigger love.textinput above.
function Text.keychord_pressed(chord)
--? print(chord)
--== shortcuts that mutate text
if chord == 'return' then
local before_line = Cursor1.line
local before = snapshot(before_line)
Text.insert_return()
if (Cursor_y + Line_height) > App.screen.height then
Text.snap_cursor_to_bottom_of_screen()
end
save_to_disk(Lines, Filename)
record_undo_event({before=before, after=snapshot(before_line, Cursor1.line)})
elseif chord == 'tab' then
local before = snapshot(Cursor1.line)
--? print(Screen_top1.line, Screen_top1.pos, Cursor1.line, Cursor1.pos, Screen_bottom1.line, Screen_bottom1.pos)
Text.insert_at_cursor('\t')
if Cursor_y >= App.screen.height - Line_height then
Text.populate_screen_line_starting_pos(Cursor1.line)
Text.snap_cursor_to_bottom_of_screen()
--? print('=>', Screen_top1.line, Screen_top1.pos, Cursor1.line, Cursor1.pos, Screen_bottom1.line, Screen_bottom1.pos)
end
save_to_disk(Lines, Filename)
record_undo_event({before=before, after=snapshot(Cursor1.line)})
elseif chord == 'backspace' then
if Selection1.line then
Text.delete_selection()
save_to_disk(Lines, Filename)
return
end
local before
if Cursor1.pos > 1 then
before = snapshot(Cursor1.line)
local byte_start = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos-1)
local byte_end = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
if byte_start then
if byte_end then
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_start-1)..string.sub(Lines[Cursor1.line].data, byte_end)
else
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_start-1)
end
Lines[Cursor1.line].fragments = nil
Cursor1.pos = Cursor1.pos-1
end
elseif Cursor1.line > 1 then
before = snapshot(Cursor1.line-1, Cursor1.line)
if Lines[Cursor1.line-1].mode == 'drawing' then
table.remove(Lines, Cursor1.line-1)
else
-- join lines
Cursor1.pos = utf8.len(Lines[Cursor1.line-1].data)+1
Lines[Cursor1.line-1].data = Lines[Cursor1.line-1].data..Lines[Cursor1.line].data
Lines[Cursor1.line-1].fragments = nil
table.remove(Lines, Cursor1.line)
end
Cursor1.line = Cursor1.line-1
end
if Text.lt1(Cursor1, Screen_top1) then
local top2 = Text.to2(Screen_top1)
top2 = Text.previous_screen_line(top2)
Screen_top1 = Text.to1(top2)
Text.redraw_all() -- if we're scrolling, reclaim all fragments to avoid memory leaks
end
assert(Text.le1(Screen_top1, Cursor1))
save_to_disk(Lines, Filename)
record_undo_event({before=before, after=snapshot(Cursor1.line)})
elseif chord == 'delete' then
if Selection1.line then
Text.delete_selection()
save_to_disk(Lines, Filename)
return
end
local before
if Cursor1.pos <= utf8.len(Lines[Cursor1.line].data) then
before = snapshot(Cursor1.line)
else
before = snapshot(Cursor1.line, Cursor1.line+1)
end
if Cursor1.pos <= utf8.len(Lines[Cursor1.line].data) then
local byte_start = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
local byte_end = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos+1)
if byte_start then
if byte_end then
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_start-1)..string.sub(Lines[Cursor1.line].data, byte_end)
else
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_start-1)
end
Lines[Cursor1.line].fragments = nil
-- no change to Cursor1.pos
end
elseif Cursor1.line < #Lines then
if Lines[Cursor1.line+1].mode == 'drawing' then
table.remove(Lines, Cursor1.line+1)
else
-- join lines
Lines[Cursor1.line].data = Lines[Cursor1.line].data..Lines[Cursor1.line+1].data
Lines[Cursor1.line].fragments = nil
table.remove(Lines, Cursor1.line+1)
end
end
save_to_disk(Lines, Filename)
record_undo_event({before=before, after=snapshot(Cursor1.line)})
--== shortcuts that move the cursor
elseif chord == 'left' then
if Selection1.line then
Selection1 = {}
end
Text.left()
elseif chord == 'right' then
if Selection1.line then
Selection1 = {}
end
Text.right()
elseif chord == 'S-left' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.left()
elseif chord == 'S-right' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.right()
-- C- hotkeys reserved for drawings, so we'll use M-
elseif chord == 'M-left' then
if Selection1.line then
Selection1 = {}
end
Text.word_left()
elseif chord == 'M-right' then
if Selection1.line then
Selection1 = {}
end
Text.word_right()
elseif chord == 'M-S-left' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.word_left()
elseif chord == 'M-S-right' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.word_right()
elseif chord == 'home' then
if Selection1.line then
Selection1 = {}
end
Cursor1.pos = 1
elseif chord == 'end' then
if Selection1.line then
Selection1 = {}
end
Cursor1.pos = utf8.len(Lines[Cursor1.line].data) + 1
elseif chord == 'S-home' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Cursor1.pos = 1
elseif chord == 'S-end' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Cursor1.pos = utf8.len(Lines[Cursor1.line].data) + 1
elseif chord == 'up' then
if Selection1.line then
Selection1 = {}
end
Text.up()
elseif chord == 'down' then
if Selection1.line then
Selection1 = {}
end
Text.down()
elseif chord == 'S-up' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.up()
elseif chord == 'S-down' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.down()
elseif chord == 'pageup' then
if Selection1.line then
Selection1 = {}
end
Text.pageup()
elseif chord == 'pagedown' then
if Selection1.line then
Selection1 = {}
end
Text.pagedown()
elseif chord == 'S-pageup' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.pageup()
elseif chord == 'S-pagedown' then
if Selection1.line == nil then
Selection1 = {line=Cursor1.line, pos=Cursor1.pos}
end
Text.pagedown()
end
end
function Text.insert_return()
local byte_offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
table.insert(Lines, Cursor1.line+1, {mode='text', data=string.sub(Lines[Cursor1.line].data, byte_offset)})
Lines[Cursor1.line].data = string.sub(Lines[Cursor1.line].data, 1, byte_offset-1)
Lines[Cursor1.line].fragments = nil
Cursor1.line = Cursor1.line+1
Cursor1.pos = 1
end
function Text.pageup()
-- duplicate some logic from love.draw
local top2 = Text.to2(Screen_top1)
--? print(App.screen.height)
local y = App.screen.height - Line_height
while y >= Margin_top do
--? print(y, top2.line)
if Screen_top1.line == 1 and Screen_top1.pos == 1 then break end
if Lines[Screen_top1.line].mode == 'text' then
y = y - Line_height
elseif Lines[Screen_top1.line].mode == 'drawing' then
y = y - 20 - Drawing.pixels(Lines[Screen_top1.line].h)
end
top2 = Text.previous_screen_line(top2)
end
Screen_top1 = Text.to1(top2)
Cursor1.line = Screen_top1.line
Cursor1.pos = Screen_top1.pos
Text.move_cursor_down_to_next_text_line_while_scrolling_again_if_necessary()
--? print(Cursor1.line, Cursor1.pos, Screen_top1.line, Screen_top1.pos)
end
function Text.pagedown()
-- If a line/paragraph gets to a page boundary, I often want to scroll
-- before I get to the bottom.
-- However, only do this if it makes forward progress.
local top2 = Text.to2(Screen_bottom1)
if top2.screen_line > 1 then
top2.screen_line = math.max(top2.screen_line-10, 1)
end
local new_top1 = Text.to1(top2)
if Text.lt1(Screen_top1, new_top1) then
Screen_top1 = new_top1
else
Screen_top1.line = Screen_bottom1.line
Screen_top1.pos = Screen_bottom1.pos
end
--? print('setting top to', Screen_top1.line, Screen_top1.pos)
Cursor1.line = Screen_top1.line
Cursor1.pos = Screen_top1.pos
Text.move_cursor_down_to_next_text_line_while_scrolling_again_if_necessary()
--? print('top now', Screen_top1.line)
Text.redraw_all() -- if we're scrolling, reclaim all fragments to avoid memory leaks
end
function Text.up()
assert(Lines[Cursor1.line].mode == 'text')
--? print('up', Cursor1.pos, Screen_top1.pos)
local screen_line_index,screen_line_starting_pos = Text.pos_at_start_of_cursor_screen_line()
if screen_line_starting_pos == 1 then
--? print('cursor is at first screen line of its line')
-- line is done; skip to previous text line
local new_cursor_line = Cursor1.line
while new_cursor_line > 1 do
new_cursor_line = new_cursor_line-1
if Lines[new_cursor_line].mode == 'text' then
--? print('found previous text line')
Cursor1.line = new_cursor_line
Text.populate_screen_line_starting_pos(Cursor1.line)
if Lines[Cursor1.line].screen_line_starting_pos == nil then
Cursor1.pos = Text.nearest_cursor_pos(Lines[Cursor1.line].data, Cursor_x)
break
end
-- previous text line found, pick its final screen line
--? print('has multiple screen lines')
local screen_line_starting_pos = Lines[Cursor1.line].screen_line_starting_pos
--? print(#screen_line_starting_pos)
screen_line_starting_pos = screen_line_starting_pos[#screen_line_starting_pos]
--? print('previous screen line starts at pos '..tostring(screen_line_starting_pos)..' of its line')
if Screen_top1.line > Cursor1.line then
Screen_top1.line = Cursor1.line
Screen_top1.pos = screen_line_starting_pos
--? print('pos of top of screen is also '..tostring(Screen_top1.pos)..' of the same line')
end
local s = string.sub(Lines[Cursor1.line].data, screen_line_starting_pos)
Cursor1.pos = screen_line_starting_pos + Text.nearest_cursor_pos(s, Cursor_x) - 1
break
end
end
if Cursor1.line < Screen_top1.line then
Screen_top1.line = Cursor1.line
end
else
-- move up one screen line in current line
--? print('cursor is NOT at first screen line of its line')
assert(screen_line_index > 1)
new_screen_line_starting_pos = Lines[Cursor1.line].screen_line_starting_pos[screen_line_index-1]
--? print('switching pos of screen line at cursor from '..tostring(screen_line_starting_pos)..' to '..tostring(new_screen_line_starting_pos))
if Screen_top1.line == Cursor1.line and Screen_top1.pos == screen_line_starting_pos then
Screen_top1.pos = new_screen_line_starting_pos
--? print('also setting pos of top of screen to '..tostring(Screen_top1.pos))
end
local s = string.sub(Lines[Cursor1.line].data, new_screen_line_starting_pos)
Cursor1.pos = new_screen_line_starting_pos + Text.nearest_cursor_pos(s, Cursor_x) - 1
--? print('cursor pos is now '..tostring(Cursor1.pos))
end
end
function Text.down()
assert(Lines[Cursor1.line].mode == 'text')
--? print('down', Cursor1.line, Cursor1.pos, Screen_top1.line, Screen_top1.pos, Screen_bottom1.line, Screen_bottom1.pos)
if Text.cursor_at_final_screen_line() then
-- line is done, skip to next text line
--? print('cursor at final screen line of its line')
local new_cursor_line = Cursor1.line
while new_cursor_line < #Lines do
new_cursor_line = new_cursor_line+1
if Lines[new_cursor_line].mode == 'text' then
Cursor1.line = new_cursor_line
Cursor1.pos = Text.nearest_cursor_pos(Lines[Cursor1.line].data, Cursor_x)
--? print(Cursor1.pos)
break
end
end
if Cursor1.line > Screen_bottom1.line then
--? print('screen top before:', Screen_top1.line, Screen_top1.pos)
--? print('scroll up preserving cursor')
Text.snap_cursor_to_bottom_of_screen()
--? print('screen top after:', Screen_top1.line, Screen_top1.pos)
end
else
-- move down one screen line in current line
local scroll_down = false
if Text.le1(Screen_bottom1, Cursor1) then
scroll_down = true
end
--? print('cursor is NOT at final screen line of its line')
local screen_line_index, screen_line_starting_pos = Text.pos_at_start_of_cursor_screen_line()
new_screen_line_starting_pos = Lines[Cursor1.line].screen_line_starting_pos[screen_line_index+1]
--? print('switching pos of screen line at cursor from '..tostring(screen_line_starting_pos)..' to '..tostring(new_screen_line_starting_pos))
local s = string.sub(Lines[Cursor1.line].data, new_screen_line_starting_pos)
Cursor1.pos = new_screen_line_starting_pos + Text.nearest_cursor_pos(s, Cursor_x) - 1
--? print('cursor pos is now', Cursor1.line, Cursor1.pos)
if scroll_down then
--? print('scroll up preserving cursor')
Text.snap_cursor_to_bottom_of_screen()
--? print('screen top after:', Screen_top1.line, Screen_top1.pos)
end
end
--? print('=>', Cursor1.line, Cursor1.pos, Screen_top1.line, Screen_top1.pos, Screen_bottom1.line, Screen_bottom1.pos)
end
function Text.word_left()
while true do
Text.left()
if Cursor1.pos == 1 then break end
assert(Cursor1.pos > 1)
local offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
assert(offset > 1)
if Lines[Cursor1.line].data:sub(offset-1,offset-1) == ' ' then
break
end
end
end
function Text.word_right()
while true do
Text.right()
if Cursor1.pos > utf8.len(Lines[Cursor1.line].data) then break end
local offset = utf8.offset(Lines[Cursor1.line].data, Cursor1.pos)
if Lines[Cursor1.line].data:sub(offset,offset) == ' ' then -- TODO: other space characters
break
end
end
end
function Text.left()
assert(Lines[Cursor1.line].mode == 'text')
if Cursor1.pos > 1 then
Cursor1.pos = Cursor1.pos-1
else
local new_cursor_line = Cursor1.line
while new_cursor_line > 1 do
new_cursor_line = new_cursor_line-1
if Lines[new_cursor_line].mode == 'text' then
Cursor1.line = new_cursor_line
Cursor1.pos = utf8.len(Lines[Cursor1.line].data) + 1
break
end
end
if Cursor1.line < Screen_top1.line then
Screen_top1.line = Cursor1.line
end
end
end
function Text.right()
assert(Lines[Cursor1.line].mode == 'text')
if Cursor1.pos <= utf8.len(Lines[Cursor1.line].data) then
Cursor1.pos = Cursor1.pos+1
else
local new_cursor_line = Cursor1.line
while new_cursor_line <= #Lines-1 do
new_cursor_line = new_cursor_line+1
if Lines[new_cursor_line].mode == 'text' then
Cursor1.line = new_cursor_line
Cursor1.pos = 1
break
end
end
if Cursor1.line > Screen_bottom1.line then
Screen_top1.line = Cursor1.line
end
end
end
function Text.pos_at_start_of_cursor_screen_line()
if Lines[Cursor1.line].screen_line_starting_pos == nil then
return 1,1
end
for i=#Lines[Cursor1.line].screen_line_starting_pos,1,-1 do
local spos = Lines[Cursor1.line].screen_line_starting_pos[i]
if spos <= Cursor1.pos then
return i,spos
end
end
assert(false)
end
function Text.cursor_at_final_screen_line()
if Lines[Cursor1.line].screen_line_starting_pos == nil then
return true
end
local screen_lines = Lines[Cursor1.line].screen_line_starting_pos
--? print(screen_lines[#screen_lines], Cursor1.pos)
return screen_lines[#screen_lines] <= Cursor1.pos
end
function Text.move_cursor_down_to_next_text_line_while_scrolling_again_if_necessary()
local y = Margin_top
while Cursor1.line <= #Lines do
if Lines[Cursor1.line].mode == 'text' then
break
end
--? print('cursor skips', Cursor1.line)
y = y + 20 + Drawing.pixels(Lines[Cursor1.line].h)
Cursor1.line = Cursor1.line + 1
end
-- hack: insert a text line at bottom of file if necessary
if Cursor1.line > #Lines then
assert(Cursor1.line == #Lines+1)
table.insert(Lines, {mode='text', data=''})
end
--? print(y, App.screen.height, App.screen.height-Line_height)
if y > App.screen.height - Line_height then
--? print('scroll up')
Text.snap_cursor_to_bottom_of_screen()
end
end
function Text.snap_cursor_to_bottom_of_screen()
local top2 = Text.to2(Cursor1)
top2.screen_pos = 1 -- start of screen line
--? print('cursor pos '..tostring(Cursor1.pos)..' is on the #'..tostring(top2.screen_line)..' screen line down')
local y = App.screen.height - Line_height
-- duplicate some logic from love.draw
while true do
--? print(y, 'top2:', top2.line, top2.screen_line, top2.screen_pos)
if top2.line == 1 and top2.screen_line == 1 then break end
if top2.screen_line > 1 or Lines[top2.line-1].mode == 'text' then
local h = Line_height
if y - h < Margin_top then
break
end
y = y - h
else
assert(top2.line > 1)
assert(Lines[top2.line-1].mode == 'drawing')
-- We currently can't draw partial drawings, so either skip it entirely
-- or not at all.
local h = 20 + Drawing.pixels(Lines[top2.line-1].h)
if y - h < Margin_top then
break
end
--? print('skipping drawing of height', h)
y = y - h
end
top2 = Text.previous_screen_line(top2)
end
--? print('top2 finally:', top2.line, top2.screen_line, top2.screen_pos)
Screen_top1 = Text.to1(top2)
--? print('top1 finally:', Screen_top1.line, Screen_top1.pos)
Text.redraw_all() -- if we're scrolling, reclaim all fragments to avoid memory leaks
end
function Text.in_line(line, x,y)
if line.y == nil then return false end -- outside current page
if x < 25 then return false end
if y < line.y then return false end
if line.screen_line_starting_pos == nil then return y < line.y + Line_height end
return y < line.y + #line.screen_line_starting_pos * Line_height
end
-- convert mx,my in pixels to schema-1 coordinates
function Text.to_pos_on_line(line, mx, my)
if line.screen_line_starting_pos == nil then
return Text.nearest_cursor_pos(line.data, mx)
end
if line.fragments == nil then
Text.compute_fragments(line, Line_width)
end
assert(my >= line.y)
-- duplicate some logic from Text.draw
local y = line.y
for screen_line_index,screen_line_starting_pos in ipairs(line.screen_line_starting_pos) do
local nexty = y + Line_height
if my < nexty then
-- On all wrapped screen lines but the final one, clicks past end of
-- line position cursor on final character of screen line.
-- (The final screen line positions past end of screen line as always.)
if mx > Line_width and screen_line_index < #line.screen_line_starting_pos then
return line.screen_line_starting_pos[screen_line_index+1]
end
local s = string.sub(line.data, screen_line_starting_pos)
return screen_line_starting_pos + Text.nearest_cursor_pos(s, mx) - 1
end
y = nexty
end
assert(false)
end
-- manual test:
-- line: abc
-- def
-- gh
-- fragments: abc, def, gh
-- click inside e
-- line_starting_pos = 1 + 3 = 4
-- nearest_cursor_pos('defgh', mx) = 2
-- Cursor1.pos = 4 + 2 - 1 = 5
-- manual test:
-- click inside h
-- line_starting_pos = 1 + 3 + 3 = 7
-- nearest_cursor_pos('gh', mx) = 2
-- Cursor1.pos = 7 + 2 - 1 = 8
function Text.nearest_cursor_pos(line, x) -- x includes left margin
if x == 0 then
return 1
end
local len = utf8.len(line)
local max_x = 25+Text.x(line, len+1)
if x > max_x then
return len+1
end
local left, right = 1, len+1
--? print('-- nearest', x)
while true do
--? print('nearest', x, '^'..line..'$', left, right)
if left == right then
return left
end
local curr = math.floor((left+right)/2)
local currxmin = 25+Text.x(line, curr)
local currxmax = 25+Text.x(line, curr+1)
--? print('nearest', x, left, right, curr, currxmin, currxmax)
if currxmin <= x and x < currxmax then
if x-currxmin < currxmax-x then
return curr
else
return curr+1
end
end
if left >= right-1 then
return right
end
if currxmin > x then
right = curr
else
left = curr
end
end
assert(false)
end
function Text.nearest_pos_less_than(line, x) -- x DOES NOT include left margin
if x == 0 then
return 1
end
local len = utf8.len(line)
local max_x = Text.x(line, len+1)
if x > max_x then
return len+1
end
local left, right = 1, len+1
--? print('--')
while true do
local curr = math.floor((left+right)/2)
local currxmin = Text.x(line, curr+1)
local currxmax = Text.x(line, curr+2)
--? print(x, left, right, curr, currxmin, currxmax)
if currxmin <= x and x < currxmax then
return curr
end
if left >= right-1 then
return left
end
if currxmin > x then
right = curr
else
left = curr
end
end
assert(false)
end
function Text.x(s, pos)
local offset = utf8.offset(s, pos)
assert(offset)
local s_before = s:sub(1, offset-1)
local text_before = App.newText(love.graphics.getFont(), s_before)
return App.width(text_before)
end
function Text.to2(pos1)
if Lines[pos1.line].mode == 'drawing' then
return {line=pos1.line, screen_line=1, screen_pos=1}
end
local result = {line=pos1.line, screen_line=1}
if Lines[pos1.line].screen_line_starting_pos == nil then
result.screen_pos = pos1.pos
else
for i=#Lines[pos1.line].screen_line_starting_pos,1,-1 do
local spos = Lines[pos1.line].screen_line_starting_pos[i]
if spos <= pos1.pos then
result.screen_line = i
result.screen_pos = pos1.pos - spos + 1
break
end
end
end
assert(result.screen_pos)
return result
end
function Text.to1(pos2)
local result = {line=pos2.line, pos=pos2.screen_pos}
if pos2.screen_line > 1 then
result.pos = Lines[pos2.line].screen_line_starting_pos[pos2.screen_line] + pos2.screen_pos - 1
end
return result
end
function Text.eq1(a, b)
return a.line == b.line and a.pos == b.pos
end
function Text.lt1(a, b)
if a.line < b.line then
return true
end
if a.line > b.line then
return false
end
return a.pos < b.pos
end
function Text.le1(a, b)
if a.line < b.line then
return true
end
if a.line > b.line then
return false
end
return a.pos <= b.pos
end
function Text.previous_screen_line(pos2)
if pos2.screen_line > 1 then
return {line=pos2.line, screen_line=pos2.screen_line-1, screen_pos=1}
elseif pos2.line == 1 then
return pos2
elseif Lines[pos2.line-1].mode == 'drawing' then
return {line=pos2.line-1, screen_line=1, screen_pos=1}
else
local l = Lines[pos2.line-1]
if l.screen_line_starting_pos == nil then
return {line=pos2.line-1, screen_line=1, screen_pos=1}
else
return {line=pos2.line-1, screen_line=#Lines[pos2.line-1].screen_line_starting_pos, screen_pos=1}
end
end
end
function Text.populate_screen_line_starting_pos(line_index)
--? print('Text.populate_screen_line_starting_pos')
local line = Lines[line_index]
if line.screen_line_starting_pos then
return
end
-- duplicate some logic from Text.draw
if line.fragments == nil then
Text.compute_fragments(line, Line_width)
end
local x = 25
local pos = 1
for _, f in ipairs(line.fragments) do
local frag, frag_text = f.data, f.text
--? print(x, frag)
-- render fragment
local frag_width = App.width(frag_text)
if x + frag_width > Line_width then
x = 25
if line.screen_line_starting_pos == nil then
line.screen_line_starting_pos = {1, pos}
else
--? print(' ', #line.screen_line_starting_pos, line.data)
table.insert(line.screen_line_starting_pos, pos)
end
end
x = x + frag_width
local frag_len = utf8.len(frag)
pos = pos + frag_len
end
end
function Text.redraw_all()
print('clearing fragments')
for _,line in ipairs(Lines) do
line.y = nil
line.fragments = nil
line.screen_line_starting_pos = nil
end
end
return Text