diff options
Diffstat (limited to 'font_api/font.lua')
| -rw-r--r-- | font_api/font.lua | 180 |
1 files changed, 93 insertions, 87 deletions
diff --git a/font_api/font.lua b/font_api/font.lua index 580744d..db12dba 100644 --- a/font_api/font.lua +++ b/font_api/font.lua @@ -17,59 +17,44 @@ along with this program. If not, see <http://www.gnu.org/licenses/>. --]] +-- Fallback table +local fallbacks = dofile(font_api.path.."/fallbacks.lua") + -- Local functions ------------------ --- Table deep copy - -local function deep_copy(input) - local output = {} - local key, value - for key, value in pairs(input) do - if type(value) == 'table' then - output[key] = deep_copy(value) - else - output[key] = value - end +-- Returns number of UTF8 bytes of the first char of the string +local function get_char_bytes(str) + local msb = str:byte(1) + if msb ~= nil then + if msb < 0x80 then return 1 end + if msb >= 0xF0 then return 4 end + if msb >= 0xE0 then return 3 end + if msb >= 0xC2 then return 2 end end - return output end --- Returns next char, managing ascii and unicode plane 0 (0000-FFFF). - -local function get_next_char(text, pos) - - local msb = text:byte(pos) - -- 1 byte char, ascii equivalent codepoints - if msb < 0x80 then - return msb, pos + 1 - end - - -- 4 bytes char not managed (Only 16 bits codepoints are managed) - if msb >= 0xF0 then - return 0, pos + 4 +-- Returns the unicode codepoint of the first char of the string +local function char_to_codepoint(str) + local bytes = get_char_bytes(str) + if bytes == 1 then + return str:byte(1) + elseif bytes == 2 then + return (str:byte(1) - 0xC2) * 0x40 + + str:byte(2) + elseif bytes == 3 then + return (str:byte(1) - 0xE0) * 0x1000 + + str:byte(2) % 0x40 * 0x40 + + str:byte(3) % 0x40 + elseif bytes == 4 then -- Not tested + return (str:byte(1) - 0xF0) * 0x40000 + + str:byte(2) % 0x40 * 0x1000 + + str:byte(3) % 0x40 * 0x40 + + str:byte(4) % 0x40 end - - -- 3 bytes char - if msb >= 0xE0 then - return (msb - 0xE0) * 0x1000 - + text:byte(pos + 1) % 0x40 * 0x40 - + text:byte(pos + 2) % 0x40, - pos + 3 - end - - -- 2 bytes char (little endian) - if msb >= 0xC2 then - return (msb - 0xC2) * 0x40 + text:byte(pos + 1), - pos + 2 - end - - -- Not an UTF char - return 0, pos + 1 end -- Split multiline text into array of lines, with <maxlines> maximum lines. - local function split_lines(text, maxlines) local splits = text:split("\n") if maxlines then @@ -86,42 +71,75 @@ end -------------------------------------------------------------------------------- --- Font class -font_api.Font = {} +local Font = {} +font_api.Font = Font -function font_api.Font:new(def) +function Font:new(def) if type(def) ~= "table" then - minetest.log("error", "Font definition must be a table.") + minetest.log("error", + "[font_api] Font definition must be a table.") return nil end - + if def.height == nil or def.height <= 0 then - minetest.log("error", "Font definition must have a positive height.") + minetest.log("error", + "[font_api] Font definition must have a positive height.") return nil end if type(def.widths) ~= "table" then - minetest.log("error", "Font definition must have a widths array.") + minetest.log("error", + "[font_api] Font definition must have a widths array.") return nil end if def.widths[0] == nil then - minetest.log("error", - "Font must have a char with codepoint 0 (=unknown char).") + minetest.log("error", + "[font_api] Font must have a char with codepoint 0 (=unknown char).") return nil end - local font = deep_copy(def) + local font = table.copy(def) setmetatable(font, self) self.__index = self return font end +--- Gets the next char of a text +-- @return Codepoint of first char, +-- @return Remaining string without this first char + +function Font:get_next_char(text) + local bytes = get_char_bytes(text) + + if bytes == nil then + minetest.log("warning", + "[font_api] Encountered a non UTF char, not displaying text.") + return nil, '' + end + + local codepoint = char_to_codepoint(text) + + -- Fallback mechanism + if self.widths[codepoint] == nil then + local char = text:sub(1, bytes) + + if fallbacks[char] then + return self:get_next_char(fallbacks[char]..text:sub(bytes+1)) + else + return 0, text:sub(bytes+1) -- Ultimate fallback + end + else + return codepoint, text:sub(bytes+1) + end +end + --- Returns the width of a given char -- @param char : codepoint of the char -- @return Char width -function font_api.Font:get_char_width(char) +function Font:get_char_width(char) -- Replace chars with no texture by the NULL(0) char if self.widths[char] ~= nil then return self.widths[char] @@ -134,13 +152,13 @@ end -- @param nb_of_lines : number of text lines (default 1) -- @return Text height -function font_api.Font:get_height(nb_of_lines) +function Font:get_height(nb_of_lines) if nb_of_lines == nil then nb_of_lines = 1 end - + if nb_of_lines > 0 then - return + return ( - (self.height or 0) + + (self.height or 0) + (self.margintop or 0) + (self.marginbottom or 0) ) * nb_of_lines + @@ -154,16 +172,14 @@ end -- @param line Line of text which the width will be computed. -- @return Text width -function font_api.Font:get_width(line) - - local char +function Font:get_width(line) + local codepoint local width = 0 - local pos = 1 + line = line or '' - -- TODO: Use iterator - while pos <= #line do - char, pos = get_next_char(line, pos) - width = width + self:get_char_width(char) + while line ~= "" do + codepoint, line = self:get_next_char(line) + width = width + self:get_char_width(codepoint) end return width @@ -176,30 +192,21 @@ end -- @param y Vertical position of the line in texture -- @return Texture string -function font_api.Font:make_line_texture(line, texturew, x, y) +function Font:make_line_texture(line, texturew, x, y) + local codepoint local texture = "" - local char - local pos = 1 - - -- TODO: Use iterator - while pos <= #line do - char, pos = get_next_char(line, pos) - - -- Replace chars with no texture by the NULL(0) char - if self.widths[char] == nil - then - print(string.format("["..font_api.name - .."] Missing char %d (%04x)",char,char)) - char = 0 - end + line = line or '' + + while line ~= '' do + codepoint, line = self:get_next_char(line) -- Add image only if it is visible (at least partly) - if x + self.widths[char] >= 0 and x <= texturew then + if x + self.widths[codepoint] >= 0 and x <= texturew then texture = texture.. string.format(":%d,%d=font_%s_%04x.png", - x, y, self.name, char) + x, y, self.name, codepoint) end - x = x + self.widths[char] + x = x + self.widths[codepoint] end return texture @@ -215,13 +222,13 @@ end -- @param color Color of the text (optional) -- @return Texture string -function font_api.Font:make_text_texture(text, texturew, textureh, maxlines, +function Font:make_text_texture(text, texturew, textureh, maxlines, halign, valign, color) local texture = "" local lines = {} local textheight = 0 local y - + -- Split text into lines (limited to maxlines fist lines) for num, line in pairs(split_lines(text, maxlines)) do lines[num] = { text = line, width = self:get_width(line) } @@ -238,7 +245,7 @@ function font_api.Font:make_text_texture(text, texturew, textureh, maxlines, y = (textureh - textheight) / 2 end end - + y = y + (self.margintop or 0) for _, line in pairs(lines) do @@ -263,4 +270,3 @@ function font_api.Font:make_text_texture(text, texturew, textureh, maxlines, if color then texture = texture.."^[colorize:"..color end return texture end - |