InterpolateBetween

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Revision as of 09:50, 17 December 2010 by Kayl 712 (talk | contribs)
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Interpolates a 3D Vector between a source value and a target value using either linear interpolation or any other easing function. It can also be used to interpolate 2D vectors or scalars my only setting some of the x, y, z values and putting 0 to the others.

Syntax

x, y, z = interpolateBetween ( x1, y1, z1, x2, y2, z2, fProgress, strEasingType [, fEasingPeriod, fEasingAmplitude, fEasingOvershoot] )

Required Arguments

  • x1, y1, z1: 3D coordinates of source vector
  • x2, y2, z2: 3D coordinates of target vector
  • fProgress: float between 0 and 1 indicating the interpolation progress (0 at the beginning of the interpolation, 1 at the end).
  • strEasingType: the easing function to use for the interpolation

Optional Arguments

  • fEasingPeriod: the period of the easing function (only some easing functions use this parameter)
  • fEasingAmplitude: the amplitude of the easing function (only some easing functions use this parameter)
  • fEasingOvershoot: the overshoot of the easing function (only some easing functions use this parameter)

Returns

Returns x, y, z the interpolated 3D vector if successful, false otherwise (error in parameters). As mentioned before, interpolateBetween can be used on 2D vectors or scalars in which case only some (x, y or just x) of the returned values are to be used (cf. alpha interpolation in marker example or size interpolation in window example).

Examples

Click to collapse [-]
Client

This clienstide example uses interpolateBetween to create position and color interpolation(with effect) on a marker. The command to test it is "/marker". The position is interpolated with "OutBounce" as strEasingType to make the marker bounce off the ground and "Linear" interpolation for the color. 

local g_Marker = nil
addCommandHandler("marker",
function ()
	if g_Marker then return end
	
	local x, y, z = getElementPosition(getLocalPlayer())
	z = z - 1
	
	g_Marker = {}
	g_Marker.startPos = {x, y, z + 5}
	g_Marker.startTime = getTickCount()
	g_Marker.startColor = {255, 0, 0, 0}
	g_Marker.endPos = {x, y, z}
	g_Marker.endTime = g_Marker.startTime + 2000
	g_Marker.endColor = {0, 0, 255, 255}	
	
	local x, y, z = unpack(g_Marker.startPos)
	local r, g, b, a = unpack(g_Marker.startColor)
	g_Marker.marker = createMarker(x, y, z, "cylinder", 1, 255, r, g, b, a)
		
	addEventHandler("onClientRender", getRootElement(), popMarkerUp)
end)

function popMarkerUp()
	local now = getTickCount()
	local elapsedTime = now - g_Marker.startTime
	local duration = g_Marker.endTime - g_Marker.startTime
	local progress = elapsedTime / duration

	local x1, y1, z1 = unpack(g_Marker.startPos)
	local x2, y2, z2 = unpack(g_Marker.endPos)
	local x, y, z = interpolateBetween ( 
		x1, y1, z1,
		x2, y2, z2, 
		progress, "OutBounce")
		
	setElementPosition(g_Marker.marker, x, y, z)
			
	local r1, g1, b1, a1 = unpack(g_Marker.startColor)
	local r2, g2, b2, a2 = unpack(g_Marker.endColor)
	local r, g, b = interpolateBetween ( 
		r1, g1, b1,
		r2, g2, b2, 
		progress, "Linear")
	local a = interpolateBetween ( 
		a1, 0, 0,
		a2, 0, 0,
		progress, "Linear")
		
	setMarkerColor(g_Marker.marker , r, g, b, a)
	
	if now >= g_Marker.endTime then
		removeEventHandler("onClientRender", getRootElement(), popMarkerUp)
		setTimer(
			function ()
				destroyElement(g_Marker.marker)
				g_Marker = nil
			end, 3000, 1)
	end
end
Click to collapse [-]
Client

This clienstide example uses interpolateBetween to create size and position interpolation (with effect) on a gui-window. The command to test it is "/window". When the window pops up it uses "OutElastic" as the strEasingType to create the bouncing/elastic effect. When it fades away, it uses "InQuad" to have an accelerating fading. 

local g_Window = nil
addCommandHandler("window",
function ()
	if g_Window then return end
	
	g_Window = {}
	
	local screenWidth, screenHeight = guiGetScreenSize()
	g_Window.windowWidth, g_Window.windowHeight = 400, 315
	local left = screenWidth/2 - g_Window.windowWidth/2
	local top = screenHeight/2 - g_Window.windowHeight/2
	
	g_Window.window = guiCreateWindow(left, top, g_Window.windowWidth, g_Window.windowHeight, "Interpolation on GUI", false)
	
	g_Window.closeBtn = guiCreateButton(320, 285, 75, 23, "Close", false, g_Window.window)
		
	guiWindowSetSizable(g_Window.window, false)
	guiWindowSetMovable(g_Window.window, false)
	guiSetEnabled(g_Window.window, false)
	guiSetVisible(g_Window.window, false)
	
	g_Window.startTime = getTickCount()
	g_Window.startSize = {0, 0}
	g_Window.endSize = {g_Window.windowWidth, g_Window.windowHeight}
	g_Window.endTime = g_Window.startTime + 1000
	addEventHandler("onClientRender", getRootElement(), popWindowUp)
end)

function on_closeBtn_clicked(button, state, absoluteX, absoluteY)
	if (button ~= "left") or (state ~= "up") then
		return
	end
	
	if not g_Window then return end
	
	showCursor(false)
	guiSetEnabled(g_Window.window, false)
	guiWindowSetMovable(g_Window.window, false)
	
	local screenWidth, screenHeight = guiGetScreenSize()
	local posX, posY = guiGetPosition(g_Window.window, false)
	
	g_Window.startTime = getTickCount()
	g_Window.startSize = {g_Window.windowWidth, g_Window.windowHeight}
	g_Window.startCenter = 
	{
		posX + g_Window.windowWidth/2,
		posY + g_Window.windowHeight/2,
	}
	
	g_Window.endSize = {0, 0}
	g_Window.endTime = g_Window.startTime + 1000
	g_Window.endCenter = 
	{
		screenWidth, 
		screenHeight
	}
	
	addEventHandler("onClientRender", getRootElement(), popWindowDown)
end

function popWindowUp()
	local now = getTickCount()
	local elapsedTime = now - g_Window.startTime
	local duration = g_Window.endTime - g_Window.startTime
	local progress = elapsedTime / duration
		
	local width, height, _ = interpolateBetween ( 
		g_Window.startSize[1], g_Window.startSize[2], 0, 
		g_Window.endSize[1], g_Window.endSize[2], 0, 
		progress, "OutElastic")
		
	guiSetSize(g_Window.window, width, height, false)
	
	local screenWidth, screenHeight = guiGetScreenSize()
	guiSetPosition(g_Window.window, screenWidth/2 - width/2, screenHeight/2 - height/2, false)
	
	if not guiGetVisible(g_Window.window) then
		guiSetVisible(g_Window.window, true)
		guiBringToFront(g_Window.window)
	end
	
	if now >= g_Window.endTime then
		guiSetEnabled(g_Window.window, true)
		
		guiBringToFront(g_Window.window)
		removeEventHandler("onClientRender", getRootElement(), popWindowUp)
		addEventHandler("onClientGUIClick", g_Window.closeBtn, on_closeBtn_clicked, false)
		showCursor(true)
		guiWindowSetMovable(g_Window.window, true)
	end
end

function popWindowDown()
	local now = getTickCount()
	local elapsedTime = now - g_Window.startTime
	local duration = g_Window.endTime - g_Window.startTime
	local progress = elapsedTime / duration
	
	local width, height, _ = interpolateBetween ( 
		g_Window.startSize[1], g_Window.startSize[2], 0, 
		g_Window.endSize[1], g_Window.endSize[2], 0, 
		progress, "InQuad")
		
	guiSetSize(g_Window.window, width, height, false)
	
	local centerX, centerY, _ = interpolateBetween ( 
		g_Window.startCenter[1], g_Window.startCenter[2], 0, 
		g_Window.endCenter[1], g_Window.endCenter[2], 0, 
		progress, "InQuad")
	
	guiSetPosition(g_Window.window, centerX - width/2, centerY - height/2, false)
	
	if now >= g_Window.endTime then
		removeEventHandler("onClientRender", getRootElement(), popWindowDown)
		destroyElement(g_Window.window)
		g_Window = nil
	end
end

See Also

Retrieved from "https://wiki.multitheftauto.com/wiki/InterpolateBetween?oldid=24731"