dotfiles/multimedia/.config/mpv/scripts/uosc_shared/lib/text.lua

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This file contains invisible Unicode characters

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-- https://en.wikipedia.org/wiki/Unicode_block
---@alias CodePointRange {[1]: integer; [2]: integer}
---@type CodePointRange[]
local zero_width_blocks = {
{0x0000, 0x001F}, -- C0
{0x007F, 0x009F}, -- Delete + C1
{0x034F, 0x034F}, -- combining grapheme joiner
{0x061C, 0x061C}, -- Arabic Letter Strong
{0x200B, 0x200F}, -- {zero-width space, zero-width non-joiner, zero-width joiner, left-to-right mark, right-to-left mark}
{0x2028, 0x202E}, -- {line separator, paragraph separator, Left-to-Right Embedding, Right-to-Left Embedding, Pop Directional Format, Left-to-Right Override, Right-to-Left Override}
{0x2060, 0x2060}, -- word joiner
{0x2066, 0x2069}, -- {Left-to-Right Isolate, Right-to-Left Isolate, First Strong Isolate, Pop Directional Isolate}
{0xFEFF, 0xFEFF}, -- zero-width non-breaking space
-- Some other characters can also be combined https://en.wikipedia.org/wiki/Combining_character
{0x0300, 0x036F}, -- Combining Diacritical Marks 0 BMP Inherited
{0x1AB0, 0x1AFF}, -- Combining Diacritical Marks Extended 0 BMP Inherited
{0x1DC0, 0x1DFF}, -- Combining Diacritical Marks Supplement 0 BMP Inherited
{0x20D0, 0x20FF}, -- Combining Diacritical Marks for Symbols 0 BMP Inherited
{0xFE20, 0xFE2F}, -- Combining Half Marks 0 BMP Cyrillic (2 characters), Inherited (14 characters)
-- Egyptian Hieroglyph Format Controls and Shorthand format Controls
{0x13430, 0x1345F}, -- Egyptian Hieroglyph Format Controls 1 SMP Egyptian Hieroglyphs
{0x1BCA0, 0x1BCAF}, -- Shorthand Format Controls 1 SMP Common
-- not sure how to deal with those https://en.wikipedia.org/wiki/Spacing_Modifier_Letters
{0x02B0, 0x02FF}, -- Spacing Modifier Letters 0 BMP Bopomofo (2 characters), Latin (14 characters), Common (64 characters)
}
-- All characters have the same width as the first one
---@type CodePointRange[]
local same_width_blocks = {
{0x3400, 0x4DBF}, -- CJK Unified Ideographs Extension A 0 BMP Han
{0x4E00, 0x9FFF}, -- CJK Unified Ideographs 0 BMP Han
{0x20000, 0x2A6DF}, -- CJK Unified Ideographs Extension B 2 SIP Han
{0x2A700, 0x2B73F}, -- CJK Unified Ideographs Extension C 2 SIP Han
{0x2B740, 0x2B81F}, -- CJK Unified Ideographs Extension D 2 SIP Han
{0x2B820, 0x2CEAF}, -- CJK Unified Ideographs Extension E 2 SIP Han
{0x2CEB0, 0x2EBEF}, -- CJK Unified Ideographs Extension F 2 SIP Han
{0x2F800, 0x2FA1F}, -- CJK Compatibility Ideographs Supplement 2 SIP Han
{0x30000, 0x3134F}, -- CJK Unified Ideographs Extension G 3 TIP Han
{0x31350, 0x323AF}, -- CJK Unified Ideographs Extension H 3 TIP Han
}
local width_length_ratio = 0.5
---@type integer, integer
local osd_width, osd_height = 100, 100
---Get byte count of utf-8 character at index i in str
---@param str string
---@param i integer?
---@return integer
local function utf8_char_bytes(str, i)
local char_byte = str:byte(i)
if char_byte < 0xC0 then return 1
elseif char_byte < 0xE0 then return 2
elseif char_byte < 0xF0 then return 3
elseif char_byte < 0xF8 then return 4
else return 1 end
end
---Creates an iterator for an utf-8 encoded string
---Iterates over utf-8 characters instead of bytes
---@param str string
---@return fun(): integer?, string?
local function utf8_iter(str)
local byte_start = 1
return function()
local start = byte_start
if #str < start then return nil end
local byte_count = utf8_char_bytes(str, start)
byte_start = start + byte_count
return start, str:sub(start, start + byte_count - 1)
end
end
---Extract Unicode code point from utf-8 character at index i in str
---@param str string
---@param i integer
---@return integer
local function utf8_to_unicode(str, i)
local byte_count = utf8_char_bytes(str, i)
local char_byte = str:byte(i)
local unicode = char_byte
if byte_count ~= 1 then
local shift = 2 ^ (8 - byte_count)
char_byte = char_byte - math.floor(0xFF / shift) * shift
unicode = char_byte * (2 ^ 6) ^ (byte_count - 1)
end
for j = 2, byte_count do
char_byte = str:byte(i + j - 1) - 0x80
unicode = unicode + char_byte * (2 ^ 6) ^ (byte_count - j)
end
return round(unicode)
end
---Convert Unicode code point to utf-8 string
---@param unicode integer
---@return string?
local function unicode_to_utf8(unicode)
if unicode < 0x80 then return string.char(unicode)
else
local byte_count
if unicode < 0x800 then byte_count = 2
elseif unicode < 0x10000 then byte_count = 3
elseif unicode < 0x110000 then byte_count = 4
else return end -- too big
local res = {}
local shift = 2 ^ 6
local after_shift = unicode
for _ = byte_count, 2, -1 do
local before_shift = after_shift
after_shift = math.floor(before_shift / shift)
table.insert(res, 1, before_shift - after_shift * shift + 0x80)
end
shift = 2 ^ (8 - byte_count)
table.insert(res, 1, after_shift + math.floor(0xFF / shift) * shift)
---@diagnostic disable-next-line: deprecated
return string.char(unpack(res))
end
end
---Update osd resolution if valid
---@param width integer
---@param height integer
local function update_osd_resolution(width, height)
if width > 0 and height > 0 then osd_width, osd_height = width, height end
end
mp.observe_property('osd-dimensions', 'native', function (_, dim)
if dim then update_osd_resolution(dim.w, dim.h) end
end)
local measure_bounds
do
local text_osd = mp.create_osd_overlay("ass-events")
text_osd.compute_bounds, text_osd.hidden = true, true
---@param ass_text string
---@return integer, integer, integer, integer
measure_bounds = function(ass_text)
update_osd_resolution(mp.get_osd_size())
text_osd.res_x, text_osd.res_y = osd_width, osd_height
text_osd.data = ass_text
local res = text_osd:update()
return res.x0, res.y0, res.x1, res.y1
end
end
local normalized_text_width
do
---@type {wrap: integer; bold: boolean; italic: boolean, rotate: number; size: number}
local bounds_opts = {wrap = 2, bold = false, italic = false, rotate = 0, size = 0}
---Measure text width and normalize to a font size of 1
---text has to be ass safe
---@param text string
---@param size number
---@param bold boolean
---@param italic boolean
---@param horizontal boolean
---@return number, integer
normalized_text_width = function(text, size, bold, italic, horizontal)
bounds_opts.bold, bounds_opts.italic, bounds_opts.rotate = bold, italic, horizontal and 0 or -90
local x1, y1 = nil, nil
size = size / 0.8
-- prevent endless loop
local repetitions_left = 5
repeat
size = size * 0.8
bounds_opts.size = size
local ass = assdraw.ass_new()
ass:txt(0, 0, horizontal and 7 or 1, text, bounds_opts)
_, _, x1, y1 = measure_bounds(ass.text)
repetitions_left = repetitions_left - 1
-- make sure nothing got clipped
until (x1 and x1 < osd_width and y1 < osd_height) or repetitions_left == 0
local width = (repetitions_left == 0 and not x1) and 0 or (horizontal and x1 or y1)
return width / size, horizontal and osd_width or osd_height
end
end
---Estimates character length based on utf8 byte count
---1 character length is roughly the size of a latin character
---@param char string
---@return number
local function char_length(char)
return #char > 2 and 2 or 1
end
---Estimates string length based on utf8 byte count
---Note: Making a string in the iterator with the character is a waste here,
---but as this function is only used when measuring whole string widths it's fine
---@param text string
---@return number
local function text_length(text)
if not text or text == '' then return 0 end
local text_length = 0
for _, char in utf8_iter(tostring(text)) do text_length = text_length + char_length(char) end
return text_length
end
---Finds the best orientation of text on screen and returns the estimated max size
---and if the text should be drawn horizontally
---@param text string
---@return number, boolean
local function fit_on_screen(text)
local estimated_width = text_length(text) * width_length_ratio
if osd_width >= osd_height then
-- Fill the screen as much as we can, bigger is more accurate.
return math.min(osd_width / estimated_width, osd_height), true
else
return math.min(osd_height / estimated_width, osd_width), false
end
end
---Gets next stage from cache
---@param cache {[any]: table}
---@param value any
local function get_cache_stage(cache, value)
local stage = cache[value]
if not stage then
stage = {}
cache[value] = stage
end
return stage
end
---Is measured resolution sufficient
---@param px integer
---@return boolean
local function no_remeasure_required(px)
return px >= 800 or (px * 1.1 >= osd_width and px * 1.1 >= osd_height)
end
local character_width
do
---@type {[boolean]: {[string]: {[1]: number, [2]: integer}}}
local char_width_cache = {}
---Get measured width of character
---@param char string
---@param bold boolean
---@return number, integer
character_width = function(char, bold)
---@type {[string]: {[1]: number, [2]: integer}}
local char_widths = get_cache_stage(char_width_cache, bold)
local width_px = char_widths[char]
if width_px and no_remeasure_required(width_px[2]) then return width_px[1], width_px[2] end
local unicode = utf8_to_unicode(char, 1)
for _, block in ipairs(zero_width_blocks) do
if unicode >= block[1] and unicode <= block[2] then
char_widths[char] = {0, INFINITY}
return 0, INFINITY
end
end
local measured_char = nil
for _, block in ipairs(same_width_blocks) do
if unicode >= block[1] and unicode <= block[2] then
measured_char = unicode_to_utf8(block[1])
width_px = char_widths[measured_char]
if width_px and no_remeasure_required(width_px[2]) then
char_widths[char] = width_px
return width_px[1], width_px[2]
end
break
end
end
if not measured_char then measured_char = char end
-- half as many repetitions for wide characters
local char_count = 10 / char_length(char)
local max_size, horizontal = fit_on_screen(measured_char:rep(char_count))
local size = math.min(max_size * 0.9, 50)
char_count = math.min(math.floor(char_count * max_size / size * 0.8), 100)
local enclosing_char, enclosing_width, next_char_count = '|', 0, char_count
if measured_char == enclosing_char then enclosing_char = ''
else enclosing_width = 2 * character_width(enclosing_char, bold) end
local width_ratio, width, px = nil, nil, nil
repeat
char_count = next_char_count
local str = enclosing_char .. measured_char:rep(char_count) .. enclosing_char
width, px = normalized_text_width(str, size, bold, false, horizontal)
width = width - enclosing_width
width_ratio = width * size / (horizontal and osd_width or osd_height)
next_char_count = math.min(math.floor(char_count / width_ratio * 0.9), 100)
until width_ratio < 0.05 or width_ratio > 0.5 or char_count == next_char_count
width = width / char_count
width_px = {width, px}
if char ~= measured_char then char_widths[measured_char] = width_px end
char_widths[char] = width_px
return width, px
end
end
---Calculate text width from individual measured characters
---@param text string|number
---@param bold boolean
---@return number, integer
local function character_based_width(text, bold)
local max_width = 0
local min_px = INFINITY
for line in tostring(text):gmatch("([^\n]*)\n?") do
local total_width = 0
for _, char in utf8_iter(line) do
local width, px = character_width(char, bold)
total_width = total_width + width
if px < min_px then min_px = px end
end
if total_width > max_width then max_width = total_width end
end
return max_width, min_px
end
---Measure width of whole text
---@param text string|number
---@param bold boolean
---@param italic boolean
---@return number, integer
local function whole_text_width(text, bold, italic)
text = tostring(text)
local size, horizontal = fit_on_screen(text)
return normalized_text_width(ass_escape(text), size * 0.9, bold, italic, horizontal)
end
---Scale normalized width to real width based on font size and italic
---@param opts {size: number; italic?: boolean}
---@return number, number
local function opts_factor_offset(opts)
return opts.size, opts.italic and opts.size * 0.2 or 0
end
---Scale normalized width to real width based on font size and italic
---@param opts {size: number; italic?: boolean}
---@return number
local function normalized_to_real(width, opts)
local factor, offset = opts_factor_offset(opts)
return factor * width + offset
end
do
---@type {[boolean]: {[boolean]: {[string|number]: {[1]: number, [2]: integer}}}} | {[boolean]: {[string|number]: {[1]: number, [2]: integer}}}
local width_cache = {}
---Calculate width of text with the given opts
---@param text string|number
---@return number
---@param opts {size: number; bold?: boolean; italic?: boolean}
function text_width(text, opts)
if not text or text == '' then return 0 end
---@type boolean, boolean
local bold, italic = opts.bold or options.font_bold, opts.italic or false
if options.text_width_estimation then
---@type {[string|number]: {[1]: number, [2]: integer}}
local text_width = get_cache_stage(width_cache, bold)
local width_px = text_width[text]
if width_px and no_remeasure_required(width_px[2]) then return normalized_to_real(width_px[1], opts) end
local width, px = character_based_width(text, bold)
width_cache[bold][text] = {width, px}
return normalized_to_real(width, opts)
else
---@type {[string|number]: {[1]: number, [2]: integer}}
local text_width = get_cache_stage(get_cache_stage(width_cache, bold), italic)
local width_px = text_width[text]
if width_px and no_remeasure_required(width_px[2]) then return width_px[1] * opts.size end
local width, px = whole_text_width(text, bold, italic)
width_cache[bold][italic][text] = {width, px}
return width * opts.size
end
end
end
do
---@type {[string]: string}
local cache = {}
---Get width of formatted timestamp as if all the digits were replaced with 0
---@param timestamp string
---@param opts {size: number; bold?: boolean; italic?: boolean}
---@return number
function timestamp_width(timestamp, opts)
local substitute = cache[#timestamp]
if not substitute then
substitute = timestamp:gsub('%d', '0')
cache[#timestamp] = substitute
end
return text_width(substitute, opts)
end
end
---Wrap the text at the closest opportunity to target_line_length
---@param text string
---@param opts {size: number; bold?: boolean; italic?: boolean}
---@param target_line_length number
---@return string
function wrap_text(text, opts, target_line_length)
local target_line_width = target_line_length * width_length_ratio * opts.size
local bold, scale_factor, scale_offset = opts.bold or false, opts_factor_offset(opts)
local wrap_at_chars = {' ', ' ', '-', ''}
local remove_when_wrap = {' ', ' '}
local lines = {}
for text_line in text:gmatch("([^\n]*)\n?") do
local line_width = scale_offset
local line_start = 1
local before_end = nil
local before_width = scale_offset
local before_line_start = 0
local before_removed_width = 0
for char_start, char in utf8_iter(text_line) do
local char_end = char_start + #char - 1
local can_wrap = false
for _, c in ipairs(wrap_at_chars) do
if char == c then
can_wrap = true
break
end
end
local char_width = character_width(char, bold) * scale_factor
line_width = line_width + char_width
if can_wrap or (char_end == #text_line) then
local remove = false
for _, c in ipairs(remove_when_wrap) do
if char == c then
remove = true
break
end
end
local line_width_after_remove = line_width - (remove and char_width or 0)
if line_width_after_remove < target_line_width then
before_end = remove and char_start - 1 or char_end
before_width = line_width_after_remove
before_line_start = char_end + 1
before_removed_width = remove and char_width or 0
else
if (target_line_width - before_width) <
(line_width_after_remove - target_line_width) then
lines[#lines + 1] = text_line:sub(line_start, before_end)
line_start = before_line_start
line_width = line_width - before_width - before_removed_width + scale_offset
else
lines[#lines + 1] = text_line:sub(line_start, remove and char_start - 1 or char_end)
line_start = char_end + 1
line_width = scale_offset
end
before_end = line_start
before_width = scale_offset
end
end
end
if #text_line >= line_start then lines[#lines + 1] = text_line:sub(line_start)
elseif text_line == '' then lines[#lines + 1] = '' end
end
return table.concat(lines, '\n')
end