SLashC++Programmer

'FRLRT

SuperStrict

AppTitle$ = "Fixed Rate Logic with Render Tweening"

Graphics 800,600

Local newTime:Int = MilliSecs()
Local oldtime:Int = newTime
Local dt# = 1000 / 60   '100 FPS logic
Local deltaTime#, accumulator#, alpha#, t#

global CurrentvPosX:int = 40;
global CurrentvPosY:int = 50;

global PrevvPosX:int = 40;
global PrevvPosY:int = 50;


global CurrentVelX:int = 2;
global CurrentVelY:int = 2;



SetBlend ALPHABLEND

Global imgBall:TImage = LoadImage("ball.png")
MidHandleImage imgBall

Global RenderTween:Int = False

While Not KeyHit(KEY_ESCAPE)
Cls

    newTime = MilliSecs()
    deltaTime# = (newTime - oldTime)
    oldTime = newTime

    accumulator :+ deltaTime

    While accumulator >= dt

        PrevvPosX = CurrentvPosX
        PrevvPosY  = CurrentvPosY
        CurrentvPosX = CurrentvPosX  + CurrentVelX
        CurrentvPosY = CurrentvPosY  + CurrentVelY

        If CurrentvPosY <= 0 Or CurrentvPosY  >= 600
            CurrentVelY = -CurrentVelY
        EndIf
        If CurrentvPosX <= 0 Or CurrentvPosX >= 800
            CurrentVelX = -CurrentVelX
        EndIf

        accumulator :- dt

    Wend

    alpha = accumulator / dt



    Local tx#, ty#
    If RenderTween
        tx# = CurrentvPosX * alpha + PrevvPosX * (1.0 - alpha)
        ty# = CurrentvPosY * alpha + PrevvPosY * (1.0 - alpha)
    Else
        tx# = CurrentvPosX
        ty# = CurrentvPosY
    EndIf

    DrawImage imgBall, tx#, ty#

    If KeyHit(KEY_SPACE) Then RenderTween = 1 - RenderTween
    DrawText "RenderTween: "+RenderTween,5,50


Flip 1

Wend
End