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Diffstat (limited to '')
| -rw-r--r-- | .config/mpv/scripts/uosc_shared/lib/text.lua | 421 |
1 files changed, 421 insertions, 0 deletions
diff --git a/.config/mpv/scripts/uosc_shared/lib/text.lua b/.config/mpv/scripts/uosc_shared/lib/text.lua new file mode 100644 index 0000000..7bb456f --- /dev/null +++ b/.config/mpv/scripts/uosc_shared/lib/text.lua @@ -0,0 +1,421 @@ +-- 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 +} + +---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 + +local text_osd = mp.create_osd_overlay("ass-events") +text_osd.compute_bounds, text_osd.hidden = true, true +---@type integer, integer +local osd_width, osd_height = 100, 100 +mp.observe_property('osd-dimensions', 'native', function (_, dim) + if dim then update_osd_resolution(dim.w, dim.h) end +end) + +---@param ass_text string +---@return integer, integer, integer, integer +local function measure_bounds(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 + +---@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 +local function normalized_text_width(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 + +---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 + +local width_length_ratio = 0.5 +---@type {[boolean]: {[string]: {[1]: number, [2]: integer}}} +local char_width_cache = {} + +---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 + +---Get measured width of character +---@param char string +---@param bold boolean +---@return number, integer +local function character_width(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 + +---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 + +---Get scale factor calculated from font size, bold and italic +---@param opts {size: number; bold?: boolean; italic?: boolean} +local function opts_scale_factor(opts) + return (opts.italic and 1.01 or 1) * opts.size +end + +---@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 width_px[1] * opts_scale_factor(opts) end + + local width, px = character_based_width(text, bold) + width_cache[bold][text] = {width, px} + return width * opts_scale_factor(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 + +---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 = opts.bold or false, opts_scale_factor(opts) + local wrap_at_chars = {' ', ' ', '-', '–'} + local remove_when_wrap = {' ', ' '} + local lines = {} + for text_line in text:gmatch("([^\n]*)\n?") do + local line_width = 0 + local line_start = 1 + local before_end = nil + local before_width = 0 + 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 + else + lines[#lines + 1] = text_line:sub(line_start, remove and char_start - 1 or char_end) + line_start = char_end + 1 + line_width = remove and line_width - char_width or line_width + line_width = 0 + end + before_end = line_start + before_width = 0 + 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 |