New Font:render method

This commit is contained in:
Pierre-Yves Rollo 2018-12-05 15:41:56 +01:00
parent 1d4c45e130
commit 47cb8f2cd3
3 changed files with 132 additions and 126 deletions

44
API.md
View File

@ -37,7 +37,7 @@ minetest.register_node("mymod:test_text_node", {
})
```
At this step, your node already displays text form "display_text" (hardcoded) node meta.
At this step, your node already displays text form "display_text" (by default) node meta. If you want to store your text into another meta data field, add a `meta_text` field to display entity definition.
But it uses defaults (default font, default size, default color). Likely you need something more.
@ -59,6 +59,28 @@ Then specify the char width. Two methods available:
* `halign`: Horizontal alignment: "left", "center" or "right" (default "center").
* `valign`: Vertical alignement: "top", "middle" or "bottom" (default "middle").
### Example
Using blue //botic// font, three lines height, aligned top left. Text stored in "text" node meta.
```
minetest.register_node("mymod:test_text_node", {
...
...
display_entities = {
["mymod:text"] = {
depth = -0.5 - display_api.entity_spacing,
on_display_update = font_api.on_display_update
meta_text = "text",
font_name = "botic",
color = "#0000FF",
maxlines = 3,
aspect_ratio = 0.5,
halign = "left",
valign = "top",
},
}
...
})
```
## Provided methods
### font_api.get_default_font_name()
Returns de default font name.
@ -159,19 +181,13 @@ Returns line(s) height. Takes care of top and bottom margins and line spacing.
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.
### 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.
### font:make_text_texture(text, texturew, textureh, maxlines, halign, valign, color)
### font:renter(text, texturew, textureh, style)
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).
* `textureh`: Height of the texture (extra text will be truncated).
* `style`: A table with style indications:
- `lines` or `maxlines`: Maximum number of lines (default none).
- `halign`: Horizontal text align: "left"/"center"/"right" (default "center")
- `valign`: Vertical text align: "top"/"middle"/"bottom" (default "middle")
- `color`: Color of the text (default black)

142
font.lua
View File

@ -54,20 +54,6 @@ local function char_to_codepoint(str)
end
end
-- Split multiline text into array of lines, with <maxlines> maximum lines.
-- Can not use minetest string.split as it has bug if first line(s) empty
local function split_lines(text, maxlines)
local lines = {}
local pos = 1
repeat
local found = string.find(text, "\n", pos)
found = found or #text + 1
lines[#lines + 1] = string.sub(text, pos, found - 1)
pos = found + 1
until (maxlines and (#lines >= maxlines)) or (pos > (#text + 1))
return lines
end
--------------------------------------------------------------------------------
--- Font class
@ -195,88 +181,86 @@ function Font:get_width(line)
return width
end
--- Builds texture part for a text line
-- @param line Text line to be rendered
-- @param texturew Width of the texture (extra text is not rendered)
-- @param x Starting x position in texture
-- @param y Vertical position of the line in texture
-- @return Texture string
function Font:make_line_texture(line, texturew, x, y)
local codepoint
local texture = ""
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: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:get_char_width(codepoint)
end
return texture
end
--- Builds texture for a multiline colored text
-- @param text Text to be rendered
-- @param texturew Width of the texture (extra text will be truncated)
-- @param textureh Height of the texture
-- @param maxlines Maximum number of lines
-- @param halign Horizontal text align ("left"/"center"/"right") (optional)
-- @param valign Vertical text align ("top"/"center"/"bottom") (optional)
-- @param color Color of the text (optional)
-- @return Texture string
--- Legacy make_text_texture method (replaced by "render" - Dec 2018)
function Font:make_text_texture(text, texturew, textureh, maxlines,
halign, valign, color)
local texture = ""
local lines = {}
local textheight = 0
local y
return self:render(text, texturew, textureh, {
lines = maxlines,
valign = valign,
halign = halign,
color = color
})
end
-- 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) }
--- Render text with the font in a view
-- @param text Text to be rendered
-- @param texturew Width (in pixels) of the texture (extra text will be truncated)
-- @param textureh Height (in pixels) of the texture (extra text will be truncated)
-- @param style Style of the rendering:
-- - lines: maximum number of text lines (if text is limited)
-- - halign: horizontal align ("left"/"center"/"right")
-- - valign: vertical align ("top"/"center"/"bottom")
-- - color: color of the text ("#rrggbb")
-- @return Texture string
function Font:render(text, texturew, textureh, style)
local style = style or {}
-- Split text into lines (and limit to style.lines # of lines)
local lines = {}
local pos = 1
local found, line
repeat
found = string.find(text, "\n", pos) or (#text + 1)
line = string.sub(text, pos, found - 1)
lines[#lines + 1] = { text = line, width = self:get_width(line) }
pos = found + 1
until (style.lines and (#lines >= style.lines)) or (pos > (#text + 1))
if not #lines then
return ""
end
textheight = self:get_height(#lines)
local x, y, codepoint
local texture = ""
local textheight = self:get_height(#lines)
if #lines then
if valign == "top" then
y = 0
elseif valign == "bottom" then
y = textureh - textheight
else
y = (textureh - textheight) / 2
end
if style.valign == "top" then
y = 0
elseif style.valign == "bottom" then
y = textureh - textheight
else
y = (textureh - textheight) / 2
end
y = y + (self.margintop or 0)
for _, line in pairs(lines) do
if halign == "left" then
texture = texture..
self:make_line_texture(line.text, texturew,
0, y)
elseif halign == "right" then
texture = texture..
self:make_line_texture(line.text, texturew,
texturew - line.width, y)
if style.halign == "left" then
x = 0
elseif style.halign == "right" then
x = texturew - line.width
else
texture = texture..
self:make_line_texture(line.text, texturew,
(texturew - line.width) / 2, y)
x = (texturew - line.width) / 2
end
while line.text ~= '' do
codepoint, line.text = self:get_next_char(line.text)
-- Add image only if it is visible (at least partly)
if x + self.widths[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]
end
y = y + self:get_height() + (self.linespacing or 0)
end
texture = string.format("[combine:%dx%d", texturew, textureh)..texture
if color then texture = texture.."^[colorize:"..color end
if style.color then
texture = texture.."^[colorize:"..style.color
end
return texture
end

View File

@ -39,43 +39,49 @@ dofile(font_api.path.."/fontform.lua")
function font_api.on_display_update(pos, objref)
local meta = minetest.get_meta(pos)
local text = meta:get_string("display_text")
local ndef = minetest.registered_nodes[minetest.get_node(pos).name]
local entity = objref:get_luaentity()
if entity and ndef.display_entities[entity.name] then
local def = ndef.display_entities[entity.name]
local font = font_api.get_font(meta:get_string("font") ~= ""
and meta:get_string("font") or def.font_name)
-- 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, texturew, textureh,
def.maxlines, def.halign, def.valign, def.color)},
visual_size = def.size
})
if not entity or not ndef.display_entities[entity.name] then
return
end
local def = ndef.display_entities[entity.name]
local font = font_api.get_font(meta:get_string("font") ~= ""
and meta:get_string("font") or def.font_name)
local text = meta:get_string(def.meta_text or "display_text")
-- 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:render(text, texturew, textureh, {
lines = def.maxlines or def.lines,
halign = def.halign,
valign = def.valign,
color = def.color} ) },
visual_size = def.size,
})
end
-- Compatibility