--[[--
Lines Fuse 

Another example for Fusion's drawing API. This Fuse draws one or two straight
lines in different styles (solid, dashed, ...). The Fuse will also calculate
the intersection point. You can use this feature to find out the vanishing
point in your picture. Connect other tools to the vanishing point using
"Connect To..." in their respective context menus.

----------------------------------------------------------------------
Copyright (c) 2011, Stefan Ihringer <stefan@bildfehler.de>

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be included
in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
----------------------------------------------------------------------

--]]--

version = "version 1.0, 2011-03-06"

-- change this to "CrosshairControl" if you want to adjust the positions with
-- a bigger transform widget.
previewControl = "PointControl"


FuRegisterClass("Lines", CT_Tool, {
	REGS_Name = "Lines",
	REGS_Category = "Fuses",
	REGS_OpIconString = "Lin",
	REGS_OpDescription = "Draws straight lines and calculates their intersection point.",
	REGS_Company = "Stefan Ihringer",
	REGS_URL = "http://www.bildfehler.de",
	REG_Fuse_NoEdit = true,
	REG_Fuse_NoReload = true,
	})

function Create()
	InStartPos1 = self:AddInput("Start 1", "StartPos1", {
		LINKID_DataType      = "Point",
		INPID_InputControl   = "OffsetControl",
		INPID_PreviewControl = previewControl,
		INP_DefaultX         = 0.25,
		INP_DefaultY         = 0.5,
		INP_DoNotifyChanged  = true,
		})
	InEndPos1 = self:AddInput("End 1", "EndPos1", {
		LINKID_DataType      = "Point",
		INPID_InputControl   = "OffsetControl",
		INPID_PreviewControl = previewControl,
		INP_DefaultX         = 0.75,
		INP_DefaultY         = 0.5,
		INP_DoNotifyChanged  = true,
		})
	InDrawSecondLine = self:AddInput("Draw a second line", "DrawSecondLine", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "CheckboxControl",
		INP_Default         = 0,
		INP_DoNotifyChanged = true,
		})
	InStartPos2 = self:AddInput("Start 2", "StartPos2", {
		LINKID_DataType      = "Point",
		INPID_InputControl   = "OffsetControl",
		INPID_PreviewControl = previewControl,
		INP_DefaultX         = 0.5,
		INP_DefaultY         = 0.25,
		IC_Visible           = false,
		PC_Visible           = false,
		INP_DoNotifyChanged  = true,
		})
	InEndPos2 = self:AddInput("End 2", "EndPos2", {
		LINKID_DataType      = "Point",
		INPID_InputControl   = "OffsetControl",
		INPID_PreviewControl = previewControl,
		INP_DefaultX         = 0.5,
		INP_DefaultY         = 0.75,
		IC_Visible           = false,
		PC_Visible           = false,
		INP_DoNotifyChanged  = true,
		})

	InShowVanishingPoint = self:AddInput("Show Vanishing Point", "ShowVanishingPoint", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "CheckboxControl",
		INP_Default         = 0,
		INP_External        = false,
		INP_Passive         = true,		-- doesn't affect rendering
		INP_DoNotifyChanged = true,
		})
	-- hidden input control, only used to display crosshairs in viewer. Updated by NotifyChanged
	InVanishingPoint = self:AddInput("Vanishing Point", "VanishingPointHidden", {
		LINKID_DataType      = "Point",
		INPID_InputControl   = "OffsetControl",
		INPID_PreviewControl = "CrosshairControl",
		CHC_Style            = "DiagonalCross",
		INP_DefaultX         = 0.5,
		INP_DefaultY         = 0.5,
		IC_Visible           = false,
		PC_Visible           = false,
		INP_External         = false,	-- don't allow connections
		INP_Passive          = true,	-- doesn't affect rendering (doesn't invalidate caches)
		INP_Disabled         = true,	-- prevent user from dragging preview control
		})

	self:BeginControlNest("Line Style", "LineStyle", false, {})
	InLineType = self:AddInput("Type", "Type", {
		LINKID_DataType    = "Number",
		INPID_InputControl = "MultiButtonControl",
		INP_Default        = 0.0,
		MBTNC_ShowName     = false,
		{MBTNC_AddButton   = "Solid", MBTNCD_ButtonWidth = 0.33, },
		{MBTNC_AddButton   = "Dash",  MBTNCD_ButtonWidth = 0.34, },
		{MBTNC_AddButton   = "Dot",   MBTNCD_ButtonWidth = 0.33, },
		{MBTNC_AddButton   = "Dash Dot",     MBTNCD_ButtonWidth = 0.5, },
		{MBTNC_AddButton   = "Dash Dot Dot", MBTNCD_ButtonWidth = 0.5, },
		})

	InThickness = self:AddInput("Thickness", "Thickness", {
		LINKID_DataType    = "Number",
		INPID_InputControl = "SliderControl",
		INP_MinAllowed     = 0,
		INP_MaxScale       = 0.1,
		INP_Default        = 0.01,
		})

	InFilter = self:AddInput("Filter", "Filter", {
		LINKID_DataType    = "Number",
		INPID_InputControl = "MultiButtonControl",
		INP_Default        = 3.0,
		{MBTNC_AddButton   = "Box",       MBTNCD_ButtonWidth = 0.25, },
		{MBTNC_AddButton   = "Bartlett",  MBTNCD_ButtonWidth = 0.25, },
		{MBTNC_AddButton   = "Multi-box", MBTNCD_ButtonWidth = 0.25, },
		{MBTNC_AddButton   = "Gaussian",  MBTNCD_ButtonWidth = 0.25, },
		})

	InSoftness = self:AddInput("Softness", "Softness", {
		LINKID_DataType    = "Number",
		INPID_InputControl = "SliderControl",
		INP_MinAllowed     = 0.0,
		INP_MaxScale       = 100,
		INP_Default        = 0.0,
		ICD_Center         = 10,
		})

	-- color wheel
	InRed = self:AddInput("Red", "Red", {
		ICS_Name            = "Line Color",
		LINKID_DataType     = "Number",
		INPID_InputControl  = "ColorControl",
		INP_Default         = 1.0,
		INP_MaxScale        = 1.0,
		CLRC_ShowWheel      = false,
		IC_ControlGroup     = 1,
		IC_ControlID        = 0,
		})
	InGreen = self:AddInput("Green", "Green", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "ColorControl",
		INP_Default         = 1.0,
		IC_ControlGroup     = 1,
		IC_ControlID        = 1,
		})
	InBlue = self:AddInput("Blue", "Blue", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "ColorControl",
		INP_Default         = 1.0,
		IC_ControlGroup     = 1,
		IC_ControlID        = 2,
		})
	InAlpha = self:AddInput("Alpha", "Alpha", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "ColorControl",
		INP_Default         = 1.0,
		IC_ControlGroup     = 1,
		IC_ControlID        = 3,
		})

	InOnBlack = self:AddInput("Draw lines on black image", "OnBlack", {
		LINKID_DataType     = "Number",
		INPID_InputControl  = "CheckboxControl",
		INP_Default         = 0,
		})
	self:EndControlNest()
	
	InLabel = self:AddInput("Lines "..version, "version", {
		LINKID_DataType    = "Text",
		INPID_InputControl = "LabelControl",
		INP_External       = false,
		INP_Passive        = true,
		})

	-- image input
	InImage = self:AddInput("Input", "Input", {
		LINKID_DataType = "Image",
		LINK_Main = 1,
		})

	-- outputs
	OutImage = self:AddOutput("Output", "Output", {
		LINKID_DataType = "Image",
		LINK_Main = 1,
		})
	OutVanishingPoint = self:AddOutput("Vanishing Point", "VanishingPoint", {
		LINKID_DataType = "Point",
		})
end


-- Find intersection of two lines, taken from http://paulbourke.net/geometry/lineline2d/
-- Returns a Point object or nil if the lines don't intersect.
function LineIntersect(x1,y1,x2,y2,x3,y3,x4,y4)
	local denom  = (y4-y3) * (x2-x1) - (x4-x3) * (y2-y1)
	local numera = (x4-x3) * (y1-y3) - (y4-y3) * (x1-x3)
	local numerb = (x2-x1) * (y1-y3) - (y2-y1) * (x1-x3)
	if math.abs(denom) < 0.00001 then
		return nil
	else
		local mua = numera/denom
		return Point(x1 + mua*(x2 - x1), y1 + mua*(y2 - y1))
	end
end


function NotifyChanged(inp, param, time)
	-- update vanishing point whenever a line has been moved
	if inp == InStartPos1 or inp == InEndPos1 or inp == InStartPos2 or inp == InEndPos2 then
		local p1 = InStartPos1:GetSource(time)
		local p2 = InEndPos1:GetSource(time)
		local p3 = InStartPos2:GetSource(time)
		local p4 = InEndPos2:GetSource(time)
		local vp = LineIntersect(p1.X, p1.Y, p2.X, p2.Y, p3.X, p3.Y, p4.X, p4.Y)
		if vp == nil then
			vp = p2
		end
		-- temporary enable the input, then disable again to prevent user from dragging the crosshairs
		InVanishingPoint:SetAttrs({INP_Disabled = false})
		InVanishingPoint:SetSource(vp, time, 0)
		InVanishingPoint:SetAttrs({INP_Disabled = true})
	end
	
	-- show/hide vanishing point crosshairs
	if inp == InShowVanishingPoint then
		if (param.Value < 0.5) then
			InVanishingPoint:SetAttrs({PC_Visible = false})
			showCrosshairs = false
		else
			InVanishingPoint:SetAttrs({PC_Visible = true})
			showCrosshairs = true
		end
	end

	-- draw second line
	if inp == InDrawSecondLine then
		if (param.Value < 0.5) then
			-- disable
			InStartPos2:SetAttrs({IC_Visible = false, PC_Visible = false})
			InEndPos2:SetAttrs({IC_Visible = false, PC_Visible = false})
			InShowVanishingPoint:SetAttrs({IC_Visible = false})
			InVanishingPoint:SetAttrs({PC_Visible = false})
		else
			-- enable
			InStartPos2:SetAttrs({IC_Visible = true, PC_Visible = true})
			InEndPos2:SetAttrs({IC_Visible = true, PC_Visible = true})
			InShowVanishingPoint:SetAttrs({IC_Visible = true})
			InVanishingPoint:SetAttrs({PC_Visible = showCrosshairs})
		end
	end
end


-- converts y-coordinates for use in matrix math, trigonometry and Shape object functions
-- where, vertically, 1.0 isn't the image height but equals the image's width.
function convertY(y, ref_img)
	return y * (ref_img.Height * ref_img.YScale) / (ref_img.Width * ref_img.XScale)
end


-- PreCalcProcess. If not implemented, only the main output will be handled,
-- which would cause tools connected to the vanishing output to fail.
function PreCalcProcess(req)
	-- set auxilliary output first
	OutVanishingPoint:Set(req, InVanishingPoint:GetValue(req))
	-- output image with no data
	local img = InImage:GetValue(req)
	local out = Image({IMG_Like = img, IMG_NoData = true})
	OutImage:Set(req, out)
end


function Process(req)
	local img        = InImage:GetValue(req)
	local start1     = InStartPos1:GetValue(req)
	local end1       = InEndPos1:GetValue(req)
	local start2     = InStartPos2:GetValue(req)
	local end2       = InEndPos2:GetValue(req)
	local dosecond   = (InDrawSecondLine:GetValue(req).Value > 0.5)
	local linetype   = math.floor(InLineType:GetValue(req).Value + 0.5) + 1
	local thickness  = InThickness:GetValue(req).Value
	local blur       = InSoftness:GetValue(req).Value
	local filter     = math.floor(InFilter:GetValue(req).Value + 0.5) + 1
	local gain_r     = InRed:GetValue(req).Value
	local gain_g     = InGreen:GetValue(req).Value
	local gain_b     = InBlue:GetValue(req).Value
	local gain_a     = InAlpha:GetValue(req).Value
	local onblack    = (InOnBlack:GetValue(req).Value > 0.5)

	-- set auxilliary output first
	OutVanishingPoint:Set(req, InVanishingPoint:GetValue(req))
	
	local out = img:CopyOf()
	if onblack then
		out:Fill(Pixel({R = 0, G = 0, B = 0, A = 0}))
	end
	local outlinetypes = {"OLT_Solid", "OLT_Dash", "OLT_Dot", "OLT_DashDot", "OLT_DashDotDot",}
	local blurfilters  = {"BT_Box", "BT_Bartless", "BT_MultiBox", "BT_Gaussian", }

	-- draw a line
	local line1 = Shape()
	line1:MoveTo(start1.X, convertY(start1.Y, img))
	line1:LineTo(end1.X, convertY(end1.Y, img))
	-- create outline using chosen "OutlineType" and desired thickness
	line1 = line1:OutlineOfShape(thickness, outlinetypes[linetype], "OJT_Round", (req:IsQuick() and 8 or 16))
	
	if dosecond then
		-- add second line
		local line2 = Shape()
		line2:MoveTo(start2.X, convertY(start2.Y, img))
		line2:LineTo(end2.X, convertY(end2.Y, img))
		line1:AddShape( line2:OutlineOfShape(thickness, outlinetypes[linetype], "OJT_Round", (req:IsQuick() and 8 or 16)) )
	end
	
	-- put shape to image
	local ic = ImageChannel(out, 8)
	local fs = FillStyle()
	ic:SetStyleFill(fs)
	ic:ShapeFill(line1)
	local cs = ChannelStyle()
	cs.Color = Pixel({R = gain_r, G = gain_g, B = gain_b, A = gain_a})
	cs.BlurType = blurfilters[filter]
	cs.SoftnessX = blur
	cs.SoftnessY = blur
	if self.Status == "OK" then
		ic:PutToImage("CM_Merge", cs)
	end
	
	OutImage:Set(req, out)
end