Curve#() - Apply a curve to a value based on a minimum and maxiumum and curve amplitude

This code has been declared by its author to be Public Domain code.

Curve#() - Apply a curve to a value based on a minimum and maxiumum and curve amplitude by Streaksy

2010

This is kinda hard to explain but there's been many times I've needed this... for smoothly flowing movements etc.

Syntax: Curve#(val#,min#,max#,typ=3,amp#=1)

val# - point beteen minimum and maximum
min# - minimum value (floor) which acts as point A
max# - maximum value (floor) which acts as point B
typ - curve type (1=smooth in, 2=smooth out, 3=smooth both)
amp# - curve amplituted. best left as default (1)

I hope that makes sense...

My second contribution to the code archives. Hope it's useful to someone. The code's kinda rough, as usual.

;EXAMPLE
Graphics 1024,768,32,2
SetBuffer BackBuffer()

MoveMouse 300,0
typ=3
Repeat
Cls
	If KeyHit(2) Then typ=1
	If KeyHit(3) Then typ=2
	If KeyHit(4) Then typ=3
	Color 255,255,255
	Text 0,0,"1-Smooth out"
	Text 0,20,"2-Smooth in"
	Text 0,40,"3-Smooth in and out"
		For x=1 To GraphicsWidth()
		y=(x*GraphicsHeight())/GraphicsWidth()
		y2=curve(y,0,GraphicsHeight(),typ,(Float(MouseX())/300))
		y=GraphicsHeight()-y
		y2=GraphicsHeight()-y2
		y=y/2+(GraphicsHeight()*.25)
		y2=y2/2+(GraphicsHeight()*.25)
		Color 0,0,255
		Plot x,y
		Color 255,0,0
		Plot x,y2
		Next
Flip
Until KeyHit(1)






;value, value min, value max, curve type (1=smooth out, 2=smooth in, 3=smooth both (default)), curve amplitute
Function Curve#(val#,min#,max#,typ=3,amp#=1)
val=val-min
max=max-min
If amp<>1 Then olval#=val
tween#=((val/max)*90)
If typ=<1 Then cos1#=Cos(tween-90):val=cos1*max					;smooth out
If typ=2 Then cos1#=1-Cos((tween)):val=cos1*max					;smooth in
If typ=3 Then cos1#=Cos(tween-90)*Sin(tween):val=cos1*max		;smooth in and out
If amp<>1 Then dif#=olval-val:val#=olval-(dif*amp) ;amplify
Return val+min
End Function

Comments

Serpent

2010

Good code for smooth movement. I'm assuming that in your example you've effectively created a diagram for time (x axis) versus distance moved (y axis). The code works very well. One thing that from what I can see you would have to look out for when using this code is that the amplitude parameter isn't too high. From what I can see in this example, it results in a bounce effect which wouldn't be what people want most of the time. Everything works out smoothly anyway - good job.

Streaksy

2010

thanks serpent. yeh... the amplitude is more intended for values between 0 and 1. I can't think of a reason someone would want higher, but the options there ;D

Code Archives Forum