mirror of
https://github.com/koreader/koreader
synced 2024-10-31 21:20:20 +00:00
7166efd777
ImageWidget: removed 'autostretch' setting (replaced by scale_factor=0) and renamed 'autoscale' setting to 'scale_for_dpi'.
355 lines
13 KiB
Lua
355 lines
13 KiB
Lua
--[[--
|
|
ImageWidget shows an image from a file or memory
|
|
|
|
Show image from file example:
|
|
|
|
UIManager:show(ImageWidget:new{
|
|
file = "resources/info-i.png",
|
|
-- Make sure alpha is set to true if png has transparent background
|
|
-- alpha = true,
|
|
})
|
|
|
|
|
|
Show image from memory example:
|
|
|
|
UIManager:show(ImageWidget:new{
|
|
-- bitmap_buffer should be a block of memory that holds the raw
|
|
-- uncompressed bitmap.
|
|
image = bitmap_buffer,
|
|
})
|
|
|
|
]]
|
|
|
|
local Widget = require("ui/widget/widget")
|
|
local Screen = require("device").screen
|
|
local UIManager = require("ui/uimanager")
|
|
local CacheItem = require("cacheitem")
|
|
local Mupdf = require("ffi/mupdf")
|
|
local Geom = require("ui/geometry")
|
|
local Cache = require("cache")
|
|
local logger = require("logger")
|
|
|
|
local ImageCache = Cache:new{
|
|
max_memsize = 2*1024*1024, -- 2M of image cache
|
|
current_memsize = 0,
|
|
cache = {},
|
|
-- this will hold the LRU order of the cache
|
|
cache_order = {}
|
|
}
|
|
|
|
local ImageCacheItem = CacheItem:new{}
|
|
|
|
function ImageCacheItem:onFree()
|
|
if self.bb.free then
|
|
logger.dbg("free image blitbuffer", self.bb)
|
|
self.bb:free()
|
|
end
|
|
end
|
|
|
|
local ImageWidget = Widget:new{
|
|
-- Can be provided with a path to a file
|
|
file = nil,
|
|
-- or an already made BlitBuffer (ie: made by Mupdf.renderImage())
|
|
image = nil,
|
|
|
|
-- Whether BlitBuffer rendered from file should be cached
|
|
file_do_cache = true,
|
|
-- Whether provided BlitBuffer can be modified by us and SHOULD be free() by us,
|
|
-- normally true unless our caller wants to reuse it's provided image
|
|
image_disposable = true,
|
|
|
|
-- Width and height of container, to limit rendering to this area
|
|
-- (if provided, and scale_factor is nil, image will be resized to
|
|
-- these width and height without regards to original aspect ratio)
|
|
width = nil,
|
|
height = nil,
|
|
|
|
hide = nil, -- to not be painted
|
|
|
|
-- Settings that apply at paintTo() time
|
|
invert = nil,
|
|
dim = nil,
|
|
alpha = false, -- honors alpha values from the image
|
|
|
|
-- When rotation_angle is not 0, native image is rotated by this angle
|
|
-- before scaling.
|
|
rotation_angle = 0,
|
|
|
|
-- If scale_for_dpi is true image will be rescaled according to screen dpi
|
|
-- (x2 if DPI > 332) - (formerly known as 'autoscale')
|
|
scale_for_dpi = false,
|
|
|
|
-- When scale_factor is not nil, native image is scaled by this factor
|
|
-- (if scale_factor == 1, native image size is kept)
|
|
-- Special case : scale_factor == 0 : image will be scaled to best fit provided
|
|
-- width and height, keeping aspect ratio (scale_factor will be updated
|
|
-- from 0 to the factor used at _render() time)
|
|
-- (former 'autostrech' setting removed, use "scale_factor=0" instead)
|
|
scale_factor = nil,
|
|
|
|
-- For initial positionning, if (possibly scaled) image overflows width/height
|
|
center_x_ratio = 0.5, -- default is centered on image's center
|
|
center_y_ratio = 0.5,
|
|
|
|
-- For pan & zoom management:
|
|
-- offsets to use in blitFrom()
|
|
_offset_x = 0,
|
|
_offset_y = 0,
|
|
-- limits to center_x_ratio variation around 0.5 (0.5 +/- these values)
|
|
-- to keep image centered (0 means center_x_ratio will be forced to 0.5)
|
|
_max_off_center_x_ratio = 0,
|
|
_max_off_center_y_ratio = 0,
|
|
|
|
-- So we can reset self.scale_factor to its initial value in free(), in
|
|
-- case this same object is free'd but re-used and and re-render'ed
|
|
_initial_scale_factor = nil,
|
|
|
|
_bb = nil,
|
|
_bb_disposable = true, -- whether we should free() our _bb
|
|
_bb_w = nil,
|
|
_bb_h = nil,
|
|
}
|
|
|
|
function ImageWidget:_loadimage()
|
|
self._bb = self.image
|
|
-- don't touch or free if caller doesn't want that
|
|
self._bb_disposable = self.image_disposable
|
|
end
|
|
|
|
function ImageWidget:_loadfile()
|
|
local itype = string.lower(string.match(self.file, ".+%.([^.]+)") or "")
|
|
if itype == "png" or itype == "jpg" or itype == "jpeg"
|
|
or itype == "tiff" then
|
|
local hash = "image|"..self.file.."|"..(self.width or "").."|"..(self.height or "")
|
|
local cache = ImageCache:check(hash)
|
|
if cache then
|
|
-- hit cache
|
|
self._bb = cache.bb
|
|
self._bb_disposable = false -- don't touch or free a cached _bb
|
|
else
|
|
if not self.file_do_cache then
|
|
self._bb = Mupdf.renderImageFile(self.file, self.width, self.height)
|
|
self._bb_disposable = true -- we made it, we can modify and free it
|
|
else
|
|
-- cache this image
|
|
logger.dbg("cache", hash)
|
|
cache = ImageCacheItem:new{
|
|
bb = Mupdf.renderImageFile(self.file, self.width, self.height),
|
|
}
|
|
cache.size = cache.bb.pitch * cache.bb.h * cache.bb:getBpp() / 8
|
|
ImageCache:insert(hash, cache)
|
|
self._bb = cache.bb
|
|
self._bb_disposable = false -- don't touch or free a cached _bb
|
|
end
|
|
end
|
|
else
|
|
error("Image file type not supported.")
|
|
end
|
|
end
|
|
|
|
function ImageWidget:_render()
|
|
if self._bb then -- already rendered
|
|
return
|
|
end
|
|
logger.dbg("ImageWidget: _render'ing")
|
|
if self.image then
|
|
self:_loadimage()
|
|
elseif self.file then
|
|
self:_loadfile()
|
|
else
|
|
error("cannot render image")
|
|
end
|
|
|
|
-- Store initial scale factor
|
|
self._initial_scale_factor = self.scale_factor
|
|
|
|
-- First, rotation
|
|
if self.rotation_angle ~= 0 then
|
|
if not self._bb_disposable then
|
|
-- we can't modify _bb, make a copy
|
|
self._bb = self._bb:copy()
|
|
self._bb_disposable = true -- new object will have to be freed
|
|
end
|
|
self._bb:rotate(self.rotation_angle) -- rotate in-place
|
|
end
|
|
|
|
local bb_w, bb_h = self._bb:getWidth(), self._bb:getHeight()
|
|
|
|
-- scale_for_dpi setting: update scale_factor (even if not set) with it
|
|
if self.scale_for_dpi then
|
|
local dpi_scale = Screen:getDPI() / 167
|
|
-- rounding off to power of 2 to avoid alias with pow(2, floor(log(x)/log(2))
|
|
dpi_scale = math.pow(2, math.max(0, math.floor(math.log(dpi_scale)/0.69)))
|
|
if self.scale_factor == nil then
|
|
self.scale_factor = 1
|
|
end
|
|
self.scale_factor = self.scale_factor * dpi_scale
|
|
end
|
|
|
|
-- scale to best fit container : compute scale_factor for that
|
|
if self.scale_factor == 0 then
|
|
if self.width and self.height then
|
|
self.scale_factor = math.min(self.width / bb_w, self.height / bb_h)
|
|
logger.dbg("ImageWidget: scale to fit, setting scale_factor to", self.scale_factor)
|
|
else
|
|
-- no width and height provided (inconsistencies from caller),
|
|
self.scale_factor = 1 -- native image size
|
|
end
|
|
end
|
|
|
|
-- replace blitbuffer with a resizd one if needed
|
|
local new_bb = nil
|
|
if self.scale_factor == nil then
|
|
-- no scaling, but strech to width and height, only if provided
|
|
if self.width and self.height then
|
|
logger.dbg("ImageWidget: stretching")
|
|
new_bb = self._bb:scale(self.width, self.height)
|
|
end
|
|
elseif self.scale_factor ~= 1 then
|
|
-- scale by scale_factor (not needed if scale_factor == 1)
|
|
logger.dbg("ImageWidget: scaling by", self.scale_factor)
|
|
new_bb = self._bb:scale(bb_w * self.scale_factor, bb_h * self.scale_factor)
|
|
end
|
|
if new_bb then
|
|
-- We made a new blitbuffer, we need to explicitely free
|
|
-- the old one to not leak memory
|
|
if self._bb_disposable then
|
|
self._bb:free()
|
|
end
|
|
self._bb = new_bb
|
|
self._bb_disposable = true -- new object will have to be freed
|
|
bb_w, bb_h = self._bb:getWidth(), self._bb:getHeight()
|
|
end
|
|
|
|
-- deal with positionning
|
|
if self.width and self.height then
|
|
-- if image is bigger than paint area, allow center_ratio variation
|
|
-- around 0.5 so we can pan till image border
|
|
if bb_w > self.width then
|
|
self._max_off_center_x_ratio = 0.5 - self.width/2 / bb_w
|
|
end
|
|
if bb_h > self.height then
|
|
self._max_off_center_y_ratio = 0.5 - self.height/2 / bb_h
|
|
end
|
|
-- correct provided center ratio if out limits
|
|
if self.center_x_ratio < 0.5 - self._max_off_center_x_ratio then
|
|
self.center_x_ratio = 0.5 - self._max_off_center_x_ratio
|
|
elseif self.center_x_ratio > 0.5 + self._max_off_center_x_ratio then
|
|
self.center_x_ratio = 0.5 + self._max_off_center_x_ratio
|
|
end
|
|
if self.center_y_ratio < 0.5 - self._max_off_center_y_ratio then
|
|
self.center_y_ratio = 0.5 - self._max_off_center_y_ratio
|
|
elseif self.center_y_ratio > 0.5 + self._max_off_center_y_ratio then
|
|
self.center_y_ratio = 0.5 + self._max_off_center_y_ratio
|
|
end
|
|
-- set offsets to reflect center ratio, whether oversized or not
|
|
self._offset_x = self.center_x_ratio * bb_w - self.width/2
|
|
self._offset_y = self.center_y_ratio * bb_h - self.height/2
|
|
logger.dbg("ImageWidget: initial offsets", self._offset_x, self._offset_y)
|
|
end
|
|
|
|
-- store final bb's width and height
|
|
self._bb_w = bb_w
|
|
self._bb_h = bb_h
|
|
end
|
|
|
|
function ImageWidget:getSize()
|
|
self:_render()
|
|
-- getSize will be used by the widget stack for centering/padding
|
|
if not self.width or not self.height then
|
|
-- no width/height provided, return bb size to let widget stack do the centering
|
|
return Geom:new{ w = self._bb:getWidth(), h = self._bb:getHeight() }
|
|
end
|
|
-- if width or height provided, return them as is, even if image is smaller
|
|
-- and would be centered: we'll do the centering ourselves with offsets
|
|
return Geom:new{ w = self.width, h = self.height }
|
|
end
|
|
|
|
function ImageWidget:getScaleFactor()
|
|
-- return computed scale_factor, useful if 0 (scale to fit) was used
|
|
return self.scale_factor
|
|
end
|
|
|
|
function ImageWidget:getPanByCenterRatio(x, y)
|
|
-- returns center ratio (without limits check) we would get with this panBy
|
|
local center_x_ratio = (x + self._offset_x + self.width/2) / self._bb_w
|
|
local center_y_ratio = (y + self._offset_y + self.height/2) / self._bb_h
|
|
return center_x_ratio, center_y_ratio
|
|
end
|
|
|
|
function ImageWidget:panBy(x, y)
|
|
-- update center ratio from new offset
|
|
self.center_x_ratio = (x + self._offset_x + self.width/2) / self._bb_w
|
|
self.center_y_ratio = (y + self._offset_y + self.height/2) / self._bb_h
|
|
-- correct new center ratio if out limits
|
|
if self.center_x_ratio < 0.5 - self._max_off_center_x_ratio then
|
|
self.center_x_ratio = 0.5 - self._max_off_center_x_ratio
|
|
elseif self.center_x_ratio > 0.5 + self._max_off_center_x_ratio then
|
|
self.center_x_ratio = 0.5 + self._max_off_center_x_ratio
|
|
end
|
|
if self.center_y_ratio < 0.5 - self._max_off_center_y_ratio then
|
|
self.center_y_ratio = 0.5 - self._max_off_center_y_ratio
|
|
elseif self.center_y_ratio > 0.5 + self._max_off_center_y_ratio then
|
|
self.center_y_ratio = 0.5 + self._max_off_center_y_ratio
|
|
end
|
|
-- new offsets that reflect this new center ratio
|
|
local new_offset_x = self.center_x_ratio * self._bb_w - self.width/2
|
|
local new_offset_y = self.center_y_ratio * self._bb_h - self.height/2
|
|
-- only trigger screen refresh it we actually pan
|
|
if new_offset_x ~= self._offset_x or new_offset_y ~= self._offset_y then
|
|
self._offset_x = new_offset_x
|
|
self._offset_y = new_offset_y
|
|
UIManager:setDirty("all", function()
|
|
return "partial", self.dimen
|
|
end)
|
|
end
|
|
-- return new center ratio, so caller can use them later to create a new
|
|
-- ImageWidget with a different scale_factor, while keeping center point
|
|
return self.center_x_ratio, self.center_y_ratio
|
|
end
|
|
|
|
function ImageWidget:paintTo(bb, x, y)
|
|
if self.hide then return end
|
|
-- self:_render is called in getSize method
|
|
local size = self:getSize()
|
|
self.dimen = Geom:new{
|
|
x = x, y = y,
|
|
w = size.w,
|
|
h = size.h
|
|
}
|
|
logger.dbg("blitFrom", x, y, self._offset_x, self._offset_y, size.w, size.h)
|
|
if self.alpha == true then
|
|
bb:alphablitFrom(self._bb, x, y, self._offset_x, self._offset_y, size.w, size.h)
|
|
else
|
|
bb:blitFrom(self._bb, x, y, self._offset_x, self._offset_y, size.w, size.h)
|
|
end
|
|
if self.invert then
|
|
bb:invertRect(x, y, size.w, size.h)
|
|
end
|
|
if self.dim then
|
|
bb:dimRect(x, y, size.w, size.h)
|
|
end
|
|
end
|
|
|
|
-- This will normally be called by our WidgetContainer:free()
|
|
-- But it SHOULD explicitely be called if we are getting replaced
|
|
-- (ie: in some other widget's update()), to not leak memory with
|
|
-- BlitBuffer zombies
|
|
function ImageWidget:free()
|
|
if self._bb and self._bb_disposable and self._bb.free then
|
|
self._bb:free()
|
|
self._bb = nil
|
|
end
|
|
-- reset self.scale_factor to its initial value, in case
|
|
-- self._render() is called again (happens with iconbutton,
|
|
-- avoids x2 x2 x2 if high dpi and icon scaled x8 after 3 calls)
|
|
self.scale_factor = self._initial_scale_factor
|
|
end
|
|
|
|
function ImageWidget:onCloseWidget()
|
|
-- free when UIManager:close() was called
|
|
self:free()
|
|
end
|
|
|
|
return ImageWidget
|