From 1d4c45e1309d12f186a7f657565d6aefe4200a10 Mon Sep 17 00:00:00 2001 From: Pierre-Yves Rollo Date: Wed, 5 Dec 2018 11:42:36 +0100 Subject: [PATCH] Fixed width fonts specific management --- API.md | 130 ++++++++++++++++++++++++++++++++++--------------------- font.lua | 26 +++++++---- init.lua | 27 +++++++++--- 3 files changed, 121 insertions(+), 62 deletions(-) diff --git a/API.md b/API.md index 9900a80..6c14ac4 100644 --- a/API.md +++ b/API.md @@ -7,35 +7,84 @@ Name of the font to be used when no font is given. The font should be registered If no default\_font given or if default\_font given but not registered, the first registered font will be used as default. -## Provided methods +## Use font_api with display_api (to display text on nodes) +### Base setup +Font_api offers a direct integration with display_api to display text on nodes. +First of all, create a display node with an entity. +To do this, refer to API.md in display_api mod, in particular "Howto register a display node". + +The only requirement then is to connect the `on_display_update` callback of the display entity to `font_api.on_display_update`: + +``` +minetest.register_node("mymod:test_text_node", { + ... + paramtype2 = "facedir", + ... + groups = { display_api = 1, ... }, + ... + display_entities = { + ["mymod:text"] = { + depth = -0.5 - display_api.entity_spacing, + on_display_update = font_api.on_display_update }, + } + ... + on_place = display_api.on_place, + on_construct = display_api.on_construct, + on_destruct = display_api.on_destruct, + on_rotate = display_api.on_rotate, + ... +}) +``` + +At this step, your node already displays text form "display_text" (hardcoded) node meta. + +But it uses defaults (default font, default size, default color). Likely you need something more. + +### Style your text +Font style and size can be chosen by adding some more entries to the display_entities definition table. + +#### Font size +Font size can be defined in various ways (maybe more in the future). +Start with a number of lines, and font_api will make it fit to the entity size. + * `maxlines` or `lines`: Number of maximum lines of text to be displayed. The font height will be adjusted accordingly. + +Then specify the char width. Two methods available: + * `aspect_ratio`: Defines the aspect ratio of chars. Works with all fonts. Should not be used if `columns` is specified. + * `columns`: Only if using a fixed width font, specifies the number of columns to display. + +#### Font style + * `font_name`: name of the font to use. Should correspond to a registered font (from a font mod). If not specified or font not found, default font is used. + * `color`: color to be used (default black). + * `halign`: Horizontal alignment: "left", "center" or "right" (default "center"). + * `valign`: Vertical alignement: "top", "middle" or "bottom" (default "middle"). + +## Provided methods ### font_api.get_default_font_name() Returns de default font name. ### font_api.register_font(font_name, font_def) Register a new font. -**font_name**: Name of the font to register. If registering different sizes of the same font, add size in the font name (e.g. times_10, times_12...). -**font_def**: Font definition table (see **Font definition table** below). + * `font_name`: Name of the font to register. If registering different sizes of the same font, add size in the font name (e.g. times_10, times_12...). + * `font_def`: Font definition table (see **Font definition table** below). ### font_api.on_display_update(pos, objref) Standard on_display_update entity callback. - -**pos**: Node position - -**objref**: Object reference of entity + * `pos`: Node position + * `objref`: Object reference of entity Node should have a corresponding display_entity with size, resolution and maxlines fields and optionally halign, valign and color fields. ### Font definition table Font definition table used by **font_api.register_font** and **font\_api.Font:new** may/can contain following elements: -* **height** (required): Font height in pixels (all font textures should have the same height) . -* **widths** (required): Array of character widths in pixels, indexed by UTF codepoints. -* **margintop** (optional): Margin (in texture pixels) added on top of each char texture. -* **marginbottom** (optional): Margin (in texture pixels) added at bottom of each char texture. -* **linespacing** (optional): Spacing (in texture pixels) between each lines. +* `height` (required): Font height in pixels (all font textures should have the same height) . +* `widths` (required): Array of character widths in pixels, indexed by UTF codepoints. +* `margintop` (optional): Margin (in texture pixels) added on top of each char texture. +* `marginbottom` (optional): Margin (in texture pixels) added at bottom of each char texture. +* `linespacing` (optional): Spacing (in texture pixels) between each lines. -**margintop**, **marginbottom** and **linespacing** can be negative numbers (default 0) and are to be used to adjust various font styles to each other. +`margintop`, `marginbottom` and `linespacing` can be negative numbers (default 0) and are to be used to adjust various font styles to each other. Font must have a char 0 which will be used to display any unknown char. @@ -57,7 +106,7 @@ Still in early stage of development, these tools are helpers to create font mods ### make_font_texture.sh -This scripts takes a .ttf file as input and create one .png file per char, that can be used as font texture. Launch it from your future font mod directory. +This scripts takes a .ttf file as input and create one .png file per char, that can be used as font texture. Launch it from your future font mod directory. __Advice__ @@ -95,51 +144,34 @@ __Syntax__ A font usable with font API. This class is supposed to be for internal use but who knows. ### font\_api.Font:new(def) -Create a new font object. +Create a new font object. + * `def` is a table containing font definition. See **Font definition table** above. -**def** is a table containing font definition. See **Font definition table** above. - -### font:get_char_width(char) -Returns the width of char **char** in texture pixels. - -**char**: Unicode codepoint of char. +### font:get_char_width(codepoint) +Returns the width of char `codepoint` in texture pixels. + * `codepoint`: Unicode codepoint of char. ### font:get_height(nb_of_lines) Returns line(s) height. Takes care of top and bottom margins and line spacing. - -**nb_of_lines**: Number of lines in the text. + * `nb_of_lines`: Number of lines in the text. ### font:get_width(line) - Returns the width of a text line. Beware, if line contains any new line char, they are ignored. - -**line**: Line of text which the width will be computed. + * `line`: Line of text which the width will be computed. ### font:make_line_texture(line, texturew, x, y) Create a texture for a text line. - -**line**: Line of text to be rendered in texture. - -**texturew**: Width of the texture (extra text is not rendered). - -**x**: Starting x position in texture. - -**y**: Vertical position of the line in texture. + * `line`: Line of text to be rendered in texture. + * `texturew`: Width of the texture (extra text is not rendered). + * `x`: Starting x position in texture. + * `y`: Vertical position of the line in texture. ### font:make_text_texture(text, texturew, textureh, maxlines, halign, valign, color) Builds texture for a multiline colored text. - -**text**: Text to be rendered. - -**texturew**: Width of the texture (extra text will be truncated). - -**textureh**: Height of the texture. - -**maxlines**: Maximum number of lines. - -**halign**: Horizontal text align ("left"/"center"/"right") (optional). - -**valign**: Vertical text align ("top"/"center"/"bottom") (optional). - -**color**: Color of the text (optional). - + * `text`: Text to be rendered. + * `texturew`: Width of the texture (extra text will be truncated). + * `textureh`: Height of the texture. + * `maxlines`: Maximum number of lines. + * `halign`: Horizontal text align ("left"/"center"/"right") (optional). + * `valign`: Vertical text align ("top"/"center"/"bottom") (optional). + * `color`: Color of the text (optional). diff --git a/font.lua b/font.lua index e12bb4b..a69e049 100644 --- a/font.lua +++ b/font.lua @@ -103,6 +103,16 @@ function Font:new(def) local font = table.copy(def) setmetatable(font, self) self.__index = self + + -- Check if fixedwidth + for codepoint, width in pairs(font.widths) do + font.fixedwidth = font.fixedwidth or width + if width ~= font.fixedwidth then + font.fixedwidth = nil + break + end + end + return font end @@ -138,11 +148,11 @@ end --- Returns the width of a given char -- @param char : codepoint of the char -- @return Char width - -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] +function Font:get_char_width(codepoint) + if self.fixedwidth then + return self.fixedwidth + elseif self.widths[codepoint] then + return self.widths[codepoint] else return self.widths[0] end @@ -201,12 +211,12 @@ function Font:make_line_texture(line, texturew, x, y) codepoint, line = self:get_next_char(line) -- Add image only if it is visible (at least partly) - if x + self.widths[codepoint] >= 0 and x <= texturew then + if x + self:get_char_width(codepoint) >= 0 and x <= texturew then texture = texture.. string.format(":%d,%d=font_%s_%04x.png", x, y, self.name, codepoint) end - x = x + self.widths[codepoint] + x = x + self:get_char_width(codepoint) end return texture @@ -223,7 +233,7 @@ end -- @return Texture string function Font:make_text_texture(text, texturew, textureh, maxlines, - halign, valign, color) + halign, valign, color) local texture = "" local lines = {} local textheight = 0 diff --git a/init.lua b/init.lua index 27cba99..57a3f44 100644 --- a/init.lua +++ b/init.lua @@ -48,13 +48,30 @@ function font_api.on_display_update(pos, objref) local font = font_api.get_font(meta:get_string("font") ~= "" and meta:get_string("font") or def.font_name) - local maxlines = def.maxlines or 1 -- TODO:How to do w/o maxlines ? + -- Compute entity resolution accroding to given attributes + local texturew, textureh + textureh = font:get_height(def.lines or def.maxlines or 1) + + if def.columns then + if font.fixedwidth then + texturew = def.columns * font.fixedwidth + if def.aspect_ratio then + minetest.log('warning', "[font_api] 'aspect_ratio' ignored because 'columns' is specified") + end + else + minetest.log('warning', "[font_api] 'columns' ignored because '"..font.name.."' is not a fixed width font.") + end + end + + if not texturew then + if not def.aspect_ratio then + minetest.log('warning', "[font_api] No 'aspect_ratio' specified, using default 1.") + end + texturew = textureh * def.size.x / def.size.y / (def.aspect_ratio or 1) + end objref:set_properties({ - textures={font:make_text_texture(text, - font:get_height(maxlines) * def.size.x / def.size.y - / (def.aspect_ratio or 1), - font:get_height(maxlines), + textures={font:make_text_texture(text, texturew, textureh, def.maxlines, def.halign, def.valign, def.color)}, visual_size = def.size })