mirror of
https://github.com/koreader/koreader
synced 2024-10-31 21:20:20 +00:00
277 lines
8.2 KiB
Lua
277 lines
8.2 KiB
Lua
local Blitbuffer = require("ffi/blitbuffer")
|
|
local Widget = require("ui/widget/widget")
|
|
local RenderText = require("ui/rendertext")
|
|
local Screen = require("ui/screen")
|
|
local Geom = require("ui/geometry")
|
|
|
|
-- TODO: rename string:gsplit definition
|
|
|
|
--[[
|
|
A TextWidget that handles long text wrapping
|
|
--]]
|
|
local TextBoxWidget = Widget:new{
|
|
text = nil,
|
|
face = nil,
|
|
bold = nil,
|
|
fgcolor = Blitbuffer.COLOR_BLACK,
|
|
width = 400, -- in pixels
|
|
height = nil,
|
|
first_line = 1,
|
|
virtual_line = 1, -- used by scroll bar
|
|
line_height = 0.3, -- in em
|
|
v_list = nil,
|
|
_bb = nil,
|
|
_length = 0,
|
|
}
|
|
|
|
function TextBoxWidget:init()
|
|
local v_list = nil
|
|
if self.height then
|
|
v_list = self:_getCurrentVerticalList()
|
|
else
|
|
v_list = self:_getVerticalList()
|
|
end
|
|
self:_render(v_list)
|
|
end
|
|
|
|
function TextBoxWidget:_wrapGreedyAlg(h_list)
|
|
local cur_line_width = 0
|
|
local cur_line = {}
|
|
local v_list = {}
|
|
|
|
for k,w in ipairs(h_list) do
|
|
cur_line_width = cur_line_width + w.width
|
|
if w.word == "\n" then
|
|
if cur_line_width > 0 then
|
|
-- hard line break
|
|
table.insert(v_list, cur_line)
|
|
cur_line = {}
|
|
cur_line_width = 0
|
|
end
|
|
elseif cur_line_width > self.width then
|
|
-- wrap to next line
|
|
table.insert(v_list, cur_line)
|
|
cur_line = {}
|
|
cur_line_width = w.width
|
|
table.insert(cur_line, w)
|
|
else
|
|
table.insert(cur_line, w)
|
|
end
|
|
end
|
|
-- handle last line
|
|
table.insert(v_list, cur_line)
|
|
|
|
return v_list
|
|
end
|
|
|
|
--[[
|
|
Lua doesn't have a string.split() function and most of the time
|
|
you don't really need it because string.gmatch() is enough.
|
|
However string.gmatch() has one significant disadvantage for me:
|
|
You can't split a string while matching both the delimited
|
|
strings and the delimiters themselves without tracking positions
|
|
and substrings. The string.gsplit() function below takes care of
|
|
this problem.
|
|
Author: Peter Odding
|
|
License: MIT/X11
|
|
Source: http://snippets.luacode.org/snippets/String_splitting_130
|
|
--]]
|
|
function string:gsplit(pattern, capture)
|
|
pattern = pattern and tostring(pattern) or '%s+'
|
|
if (''):find(pattern) then
|
|
error('pattern matches empty string!', 2)
|
|
end
|
|
return coroutine.wrap(function()
|
|
local index = 1
|
|
repeat
|
|
local first, last = self:find(pattern, index)
|
|
if first and last then
|
|
if index < first then
|
|
coroutine.yield(self:sub(index, first - 1))
|
|
end
|
|
if capture then
|
|
coroutine.yield(self:sub(first, last))
|
|
end
|
|
index = last + 1
|
|
else
|
|
if index <= #self then
|
|
coroutine.yield(self:sub(index))
|
|
end
|
|
break
|
|
end
|
|
until index > #self
|
|
end)
|
|
end
|
|
|
|
function TextBoxWidget:_getVerticalList(alg)
|
|
if self.vertical_list then
|
|
return self.vertical_list
|
|
end
|
|
-- build horizontal list
|
|
local h_list = {}
|
|
local line_count = 0
|
|
for line in self.text:gsplit("\n", true) do
|
|
for words in line:gmatch("[\32-\127\192-\255]+[\128-\191]*") do
|
|
for word in words:gsplit("%s+", true) do
|
|
for w in word:gsplit("%p+", true) do
|
|
local word_box = {}
|
|
word_box.word = w
|
|
word_box.width = RenderText:sizeUtf8Text(0, Screen:getWidth(), self.face, w, true, self.bold).x
|
|
table.insert(h_list, word_box)
|
|
end
|
|
end
|
|
end
|
|
if line:sub(-1) == "\n" then table.insert(h_list, {word = '\n', width = 0}) end
|
|
end
|
|
|
|
-- @TODO check alg here 25.04 2012 (houqp)
|
|
-- @TODO replace greedy algorithm with K&P algorithm 25.04 2012 (houqp)
|
|
self.vertical_list = self:_wrapGreedyAlg(h_list)
|
|
return self.vertical_list
|
|
end
|
|
|
|
function TextBoxWidget:_getCurrentVerticalList()
|
|
local line_height = (1 + self.line_height) * self.face.size
|
|
local v_list = self:_getVerticalList()
|
|
local current_v_list = {}
|
|
local height = 0
|
|
for i = self.first_line, #v_list do
|
|
if height < self.height - line_height then
|
|
table.insert(current_v_list, v_list[i])
|
|
height = height + line_height
|
|
else
|
|
break
|
|
end
|
|
end
|
|
return current_v_list
|
|
end
|
|
|
|
function TextBoxWidget:_getPreviousVerticalList()
|
|
local line_height = (1 + self.line_height) * self.face.size
|
|
local v_list = self:_getVerticalList()
|
|
local previous_v_list = {}
|
|
local height = 0
|
|
if self.first_line == 1 then
|
|
return self:_getCurrentVerticalList()
|
|
end
|
|
self.virtual_line = self.first_line
|
|
for i = self.first_line - 1, 1, -1 do
|
|
if height < self.height - line_height then
|
|
table.insert(previous_v_list, 1, v_list[i])
|
|
height = height + line_height
|
|
self.virtual_line = self.virtual_line - 1
|
|
else
|
|
break
|
|
end
|
|
end
|
|
for i = self.first_line, #v_list do
|
|
if height < self.height - line_height then
|
|
table.insert(previous_v_list, v_list[i])
|
|
height = height + line_height
|
|
else
|
|
break
|
|
end
|
|
end
|
|
if self.first_line > #previous_v_list then
|
|
self.first_line = self.first_line - #previous_v_list
|
|
else
|
|
self.first_line = 1
|
|
end
|
|
return previous_v_list
|
|
end
|
|
|
|
function TextBoxWidget:_getNextVerticalList()
|
|
local line_height = (1 + self.line_height) * self.face.size
|
|
local v_list = self:_getVerticalList()
|
|
local current_v_list = self:_getCurrentVerticalList()
|
|
local next_v_list = {}
|
|
local height = 0
|
|
if self.first_line + #current_v_list > #v_list then
|
|
return current_v_list
|
|
end
|
|
self.virtual_line = self.first_line
|
|
for i = self.first_line + #current_v_list, #v_list do
|
|
if height < self.height - line_height then
|
|
table.insert(next_v_list, v_list[i])
|
|
height = height + line_height
|
|
self.virtual_line = self.virtual_line + 1
|
|
else
|
|
break
|
|
end
|
|
end
|
|
self.first_line = self.first_line + #current_v_list
|
|
return next_v_list
|
|
end
|
|
|
|
function TextBoxWidget:_render(v_list)
|
|
local font_height = self.face.size
|
|
local line_height_px = self.line_height * font_height
|
|
local space_w = RenderText:sizeUtf8Text(0, Screen:getWidth(), self.face, " ", true).x
|
|
local h = (font_height + line_height_px) * #v_list
|
|
self._bb = Blitbuffer.new(self.width, h)
|
|
self._bb:fill(Blitbuffer.COLOR_WHITE)
|
|
local y = font_height
|
|
local pen_x = 0
|
|
for _,l in ipairs(v_list) do
|
|
pen_x = 0
|
|
for _,w in ipairs(l) do
|
|
--@TODO Don't use kerning for monospaced fonts. (houqp)
|
|
-- refert to cb25029dddc42693cc7aaefbe47e9bd3b7e1a750 in master tree
|
|
RenderText:renderUtf8Text(self._bb, pen_x, y, self.face, w.word, true, self.bold, self.fgcolor)
|
|
pen_x = pen_x + w.width
|
|
end
|
|
y = y + line_height_px + font_height
|
|
end
|
|
-- -- if text is shorter than one line, shrink to text's width
|
|
-- if #v_list == 1 then
|
|
-- self.width = pen_x
|
|
-- end
|
|
end
|
|
|
|
function TextBoxWidget:getVirtualLineNum()
|
|
return self.virtual_line
|
|
end
|
|
|
|
function TextBoxWidget:getAllLineCount()
|
|
local v_list = self:_getVerticalList()
|
|
return #v_list
|
|
end
|
|
|
|
function TextBoxWidget:getVisLineCount()
|
|
local line_height = (1 + self.line_height) * self.face.size
|
|
return math.floor(self.height / line_height)
|
|
end
|
|
|
|
function TextBoxWidget:scrollDown()
|
|
local next_v_list = self:_getNextVerticalList()
|
|
self:free()
|
|
self:_render(next_v_list)
|
|
end
|
|
|
|
function TextBoxWidget:scrollUp()
|
|
local previous_v_list = self:_getPreviousVerticalList()
|
|
self:free()
|
|
self:_render(previous_v_list)
|
|
end
|
|
|
|
function TextBoxWidget:getSize()
|
|
if self.width and self.height then
|
|
return Geom:new{ w = self.width, h = self.height}
|
|
else
|
|
return Geom:new{ w = self.width, h = self._bb:getHeight()}
|
|
end
|
|
end
|
|
|
|
function TextBoxWidget:paintTo(bb, x, y)
|
|
bb:blitFrom(self._bb, x, y, 0, 0, self.width, self._bb:getHeight())
|
|
end
|
|
|
|
function TextBoxWidget:free()
|
|
if self._bb then
|
|
self._bb:free()
|
|
self._bb = nil
|
|
end
|
|
end
|
|
|
|
return TextBoxWidget
|