-- Line Plane intersection test

-- Init function called from K3dEngine during initialization
-- Warning -- Don't delete this function -- Function must exist
function Init()
	print ("___ intr_line_plane_script out = Init() function called")
	K3d_LoadMap("./maps/test/intr_line_plane_map.lua")
	-- Include script with global variables definitions
	K3d_IncludeScript("scripts/global_var_script.lua")
	InitScene()
	
end

-- Update function called from K3dEngine during update scene
-- Warning -- Don't delete this function -- Function must exist
function Update()
	UpdateScene()
	if K3d_CheckKeyboardKey("Esc") then
		-- Load new script and delete this script
		-- This function must be called as last function in this script
		-- else engine shut down in next funcion
		-- because next function doesn`t exist in new script
		K3d_LoadNewScript("./scripts/main_menu_script.lua")
	end
end

-- Delete function called from K3dEngine during delete scene
-- Warning -- Don't delete this function -- Function must exist
function Delete()
	print("___ intr_line_plane_script out = Delete() function called")
end


-- Line and plane objects
g_iLine = -1
g_iPlane = -1
-- Ray for aiming test
g_iRay = -1
-- Spheres for aiming test
g_iSphereLine = -1
g_iSpherePlane = -1
-- Intersection point
g_iIntrPoint = -1
-- Index of selected sphere
g_iSelectedSphereId = -1
-- Camera object
g_iCamera = -1

-- Init scene in scene initialization
function InitScene()

	-- Your some scene initialization
	print("___ intr_line_plane_script out = InitScene() function called")
	g_iLine = K3d_GetObject("Line0", ObjType.iLineObj)
	print("___ intr_line_plane_script out = g_iLine =", g_iLine)
	if g_iLine == -1 then
		return false
	end
	K3d_Hide(g_iLine, ObjType.iLineObj, false);
	g_iPlane = K3d_GetObject("Plane0", ObjType.iPlaneObj)
	print("___ intr_line_plane_script out = g_iPlane =", g_iPlane)
	if g_iPlane == -1 then
		return false
	end
	K3d_Hide(g_iPlane, ObjType.iPlaneObj, false);
	g_iRay = K3d_GetObject("AimingRay", ObjType.iRayObj)
	print("___ intr_line_plane_script out = g_iRay =", g_iRay)
	if g_iRay == -1 then
		print("Ray doesn`t exists.")
		return false
	end
	g_iSphereLine = K3d_GetObject("LineBoundSphere", ObjType.iSphereObj)
	print("___ intr_line_plane_script out = g_iSphereLine =", g_iSphereLine)
	if g_iSphereLine == -1 then
		print("___ intr_line_plane_script out = LineBoundSphere doesn`t exists.")
		return false
	end
	g_iSpherePlane = K3d_GetObject("PlaneBoundSphere", ObjType.iSphereObj)
	print("___ intr_line_plane_script out = g_iSpherePlane =", g_iSpherePlane)
	if g_iSpherePlane == -1 then
		print("___ intr_line_plane_script out = g_iSpherePlane doesn`t exists.")
		return false
	end
	g_iCamera = K3d_GetObject("MainCamera", ObjType.iCameraObj)
	print("___ intr_line_plane_script out = g_iCamera =", g_iCamera)
	if g_iCamera == -1 then
		print("___ intr_line_plane_script out = g_iCamera doesn`t exists.")
		return false
	end
	CreateIntrPoint()
	-- Link plane to the sphere
	K3d_Link(g_iPlane, g_iSpherePlane, ObjType.iPlaneObj, ObjType.iSphereObj)
	-- Link line to the sphere
	K3d_Link(g_iLine, g_iSphereLine, ObjType.iLineObj, ObjType.iSphereObj)
	return true
end

-- Update scene in every frame
function UpdateScene()
	-- Your some scene updates
	K3d_Print("K3dEngine 0.1")
	K3d_Print("Test intersection between line and plane")
	IntrLinePlane()
	IntrRaySphere()
end

-- Create default intersection point
function CreateIntrPoint()
	local r=255
	local g=0
	local b=0
	local size=5
	g_iIntrPoint = K3d_AddVertex(0,0,0,r,g,b,size)
end

-- Move with plane
function MovePlane()
	if g_iSelectedSphereId == g_iSpherePlane then
		-- Get distance between camera and sphere positions
		--print("function MovePlane()")
		local dist = K3d_GetDistance(g_iCamera,g_iSpherePlane, ObjType.iCameraObj, ObjType.iSphereObj)
		K3d_PrintValue("Distance between camera and sphere position = " , dist)
		K3d_MoveByMouse(g_iSpherePlane)
		-- Get sphere position
		local posX, posY, posZ = K3d_GetSpherePos(g_iSpherePlane)
		K3d_PrintValue("Plane sphere pos X = " , posX)
		K3d_PrintValue("Plane sphere pos Y = " , posY)
		K3d_PrintValue("Plane sphere pos Z = " , posZ)
	end
	if K3d_IsMouseRight() then
		K3d_Print("Mouse right button clicked")
	end
	
end

-- Move with line
function MoveLine()
	if g_iSelectedSphereId == g_iSphereLine then
		-- Get distance between camera and sphere positions
		--print("function MoveLine()")
		local dist = K3d_GetDistance(g_iCamera,g_iSphereLine, ObjType.iCameraObj, ObjType.iSphereObj)
		K3d_PrintValue("Distance between camera and sphere position =" , dist)
		K3d_MoveByMouse(g_iSphereLine)
		-- Get sphere position
		local posX, posY, posZ = K3d_GetSpherePos(g_iSphereLine)
		K3d_PrintValue("Line sphere pos X = " , posX)
		K3d_PrintValue("Line sphere pos Y = " , posY)
		K3d_PrintValue("Line sphere pos Z = " , posZ)
	end

end

-- Check ray sphere intersection
function IntrRaySphere()
	-- Get aiming ray
	local aimOrigX, aimOrigY, aimOrigZ, aimDirX, aimDirY, aimDirZ
	aimOrigX, aimOrigY, aimOrigZ, aimDirX, aimDirY, aimDirZ = K3d_GetAimRay()
	-- Set ray for ray sphere intersection
	K3d_SetRay(g_iRay, aimOrigX, aimOrigY, aimOrigZ, aimDirX, aimDirY, aimDirZ)
	-- Return true if intersect ray the sphere
	local bIsIntr1 = K3d_GetIntersection(g_iRay, g_iSpherePlane,ObjType.iRayObj, ObjType.iSphereObj, 0)
	if bIsIntr1 then
		K3d_Print("Ray intersect the sphere of plane")
		if g_iSelectedSphereId == -1 or g_iSelectedSphereId == g_iSphereLine  then
			-- Set selected sphere index
			g_iSelectedSphereId = g_iSpherePlane
			K3d_SetColor(g_iSpherePlane, ObjType.iSphereObj,  255,0,0)
			K3d_SetColor(g_iSphereLine, ObjType.iSphereObj, 0,255,0)
		end
	end
	local bIsIntr2 = K3d_GetIntersection(g_iRay, g_iSphereLine,ObjType.iRayObj, ObjType.iSphereObj, 0)
	if bIsIntr2 then
		K3d_Print("Ray intersect the sphere of line")
		if g_iSelectedSphereId == -1 or g_iSelectedSphereId == g_iSpherePlane then
			-- Set selected sphere index
			g_iSelectedSphereId = g_iSphereLine
			K3d_SetColor(g_iSphereLine, ObjType.iSphereObj, 255,0,0)
			K3d_SetColor(g_iSpherePlane, ObjType.iSphereObj, 0,255,0)
		end
	end
	MovePlane()
	MoveLine()
end

-- Check line plane intersection and show intersection point
function IntrLinePlane()
	local x,y,z = 0
	-- Return if intersect line plane and x,y,z intersection point position
	bIsIntr, x, y, z = K3d_GetIntersection(g_iLine, g_iPlane,ObjType.iLineObj, ObjType.iPlaneObj, 1)
	if bIsIntr then
		K3d_Print("Line intersect the plane")
		-- Change intersection point position
		K3d_SetVertexPos(g_iIntrPoint, x,y,z)
		-- Unhide vertex
		K3d_Hide(g_iIntrPoint, ObjType.iVertexObj, false);
		K3d_PrintValue("Intr poin X = ", x)
		K3d_PrintValue("Intr poin Y = ", y)
		K3d_PrintValue("Intr poin Z = ", z)
	else
		-- Hide vertex
		K3d_Hide(g_iIntrPoint, ObjType.iVertexObj, true);
	end
end