implement full pageturn by viewport for all modes

* add notIntersectWith method for Geom
* add math.roundAwayFromZero in geometry.lua
* Readerview:recalculate now signals ViewRecalculate event.
  For now, this event is only usefull for ReaderPaging

frontend/ui/geometry.lua

@@ -137,6 +137,19 @@ function Geom:intersect(rect_b)
 	return intersected
 end
 
+--[[
+return true if self does not share any area with rect_b
+]]--
+function Geom:notIntersectWith(rect_b)
+	if (self.x >= (rect_b.x + rect_b.w)) 
+	or (self.y >= (rect_b.y + rect_b.h)) 
+	or (rect_b.x >= (self.x + self.w)) 
+	or (rect_b.y >= (self.y + self.h)) then
+		return true
+	end
+	return false
+end
+
 --[[
 set size of dimension or rectangle to size of given dimension/rectangle
 ]]--
@@ -245,3 +258,20 @@ function Geom:offsetWithin(rect_b, dx, dy)
 		self.y = rect_b.y + rect_b.h - self.h
 	end
 end
+
+
+
+
+--[[
+Simple math helper function
+]]--
+
+function math.roundAwayFromZero(num)
+	if num > 0 then
+		return math.ceil(num)
+	else
+		return math.floor(num)
+	end
+end
+
+

frontend/ui/reader/readerpaging.lua

@@ -1,6 +1,8 @@
 ReaderPaging = InputContainer:new{
 	current_page = 0,
-	number_of_pages = 0
+	number_of_pages = 0,
+	visible_area = nil,
+	page_area = nil,
 }
 
 function ReaderPaging:init()
@@ -85,10 +87,21 @@ function ReaderPaging:onReadSettings(config)
 	self:gotoPage(config:readSetting("last_page") or 1)
 end
 
+function ReaderPaging:onZoomModeUpdate(new_mode)
+	-- we need to remember zoom mode to handle page turn event
+	self.zoom_mode = new_mode
+end
+
 function ReaderPaging:onPageUpdate(new_page_no)
 	self.current_page = new_page_no
 end
 
+function ReaderPaging:onViewRecalculate(visible_area, page_area)
+	-- we need to remember areas to handle page turn event
+	self.visible_area = visible_area
+	self.page_area = page_area
+end
+
 function ReaderPaging:onGotoPercent(percent)
 	DEBUG("goto document offset in percent:", percent)
 	local dest = math.floor(self.number_of_pages * percent / 100)
@@ -102,7 +115,47 @@ end
 
 function ReaderPaging:onGotoPageRel(diff)
 	DEBUG("goto relative page:", diff)
-	self:gotoPage(self.current_page + diff)
+	local new_va = self.visible_area:copy()
+	local x_pan_off, y_pan_off = 0, 0
+
+	if self.zoom_mode:find("width") then
+		y_pan_off = self.visible_area.h * diff
+	elseif self.zoom_mode:find("height") then
+		x_pan_off = self.visible_area.w * diff
+	else
+		-- must be fit content or page zoom mode
+		if self.visible_area.w == self.page_area.w then
+			y_pan_off = self.visible_area.h * diff
+		else
+			x_pan_off = self.visible_area.w * diff
+		end
+	end
+
+	-- adjust offset to help with page turn decision
+	x_pan_off = math.roundAwayFromZero(x_pan_off)
+	y_pan_off = math.roundAwayFromZero(y_pan_off)
+	new_va.x = math.roundAwayFromZero(self.visible_area.x+x_pan_off)
+	new_va.y = math.roundAwayFromZero(self.visible_area.y+y_pan_off)
+
+	if (new_va:notIntersectWith(self.page_area)) then
+		self:gotoPage(self.current_page + diff)
+		-- if we are going back to previous page, reset
+		-- view to bottom of previous page
+		if x_pan_off < 0 then
+			self.view:PanningUpdate(self.page_area.w, 0)
+		elseif y_pan_off < 0 then
+			self.view:PanningUpdate(0, self.page_area.h)
+		end
+	else
+		-- fit new view area into page area
+		new_va:offsetWithin(self.page_area, 0, 0)
+		self.view:PanningUpdate(
+			new_va.x - self.visible_area.x,
+			new_va.y - self.visible_area.y)
+		-- update self.visible_area
+		self.visible_area = new_va
+	end
+
 	return true
 end
 

frontend/ui/reader/readerview.lua

@@ -46,7 +46,6 @@ function ReaderView:paintTo(bb, x, y)
 			self.state.zoom,
 			self.state.rotation,
 			self.render_mode)
-		self:recalculate()
 	else
 		self.ui.document:drawCurrentView(
 			bb,
@@ -81,6 +80,8 @@ function ReaderView:recalculate()
 	else
 		self.visible_area:setSizeTo(self.dimen)
 	end
+	self.ui:handleEvent(
+		Event:new("ViewRecalculate", self.visible_area, self.page_area))
 	-- flag a repaint so self:paintTo will be called
 	UIManager:setDirty(self.dialog)
 end

frontend/ui/reader/readerzooming.lua

@@ -2,35 +2,43 @@ ReaderZooming = InputContainer:new{
 	key_events = {
 		ZoomIn = {
 			{ "Shift", Input.group.PgFwd }, 
-			doc = "zoom in", event = "Zoom", args = "in" 
+			doc = "zoom in",
+			event = "Zoom", args = "in" 
 		},
 		ZoomOut = {
 			{ "Shift", Input.group.PgBack }, 
-			doc = "zoom out", event = "Zoom", args = "out" 
+			doc = "zoom out",
+			event = "Zoom", args = "out" 
 		},
 		ZoomToFitPage = {
 			{ "A" }, 
-			doc = "zoom to fit page", event = "SetZoomMode", args = "page" 
+			doc = "zoom to fit page",
+			event = "SetZoomMode", args = "page" 
 		},
 		ZoomToFitContent = {
 			{ "Shift", "A" }, 
-			doc = "zoom to fit content", event = "SetZoomMode", args = "content" 
+			doc = "zoom to fit content",
+			event = "SetZoomMode", args = "content" 
 		},
 		ZoomToFitPageWidth = {
 			{ "S" }, 
-			doc = "zoom to fit page width", event = "SetZoomMode", args = "pagewidth" 
+			doc = "zoom to fit page width",
+			event = "SetZoomMode", args = "pagewidth" 
 		},
 		ZoomToFitContentWidth = {
 			{ "Shift", "S" },
-			doc = "zoom to fit content width", event = "SetZoomMode", args = "contentwidth"
+			doc = "zoom to fit content width",
+			event = "SetZoomMode", args = "contentwidth"
 		},
 		ZoomToFitPageHeight = {
 			{ "D" }, 
-			doc = "zoom to fit page height", event = "SetZoomMode", args = "pageheight" 
+			doc = "zoom to fit page height",
+			event = "SetZoomMode", args = "pageheight" 
 		},
 		ZoomToFitContentHeight = {
 			{ "Shift", "D" },
-			doc = "zoom to fit content height", event = "SetZoomMode", args = "contentheight"
+			doc = "zoom to fit content height",
+			event = "SetZoomMode", args = "contentheight"
 		},
 	},
 	zoom = 1.0,
@@ -103,11 +111,12 @@ function ReaderZooming:onZoom(direction)
 	return true
 end
 
-function ReaderZooming:onSetZoomMode(what)
-	if self.zoom_mode ~= what then
-		DEBUG("setting zoom mode to", what)
-		self.zoom_mode = what
+function ReaderZooming:onSetZoomMode(new_mode)
+	if self.zoom_mode ~= new_mode then
+		DEBUG("setting zoom mode to", new_mode)
+		self.zoom_mode = new_mode
 		self:setZoom()
+		self.ui:handleEvent(Event:new("ZoomModeUpdate", new_mode))
 	end
 	return true
 end