Plasma effect: Difference between revisions

=={{header|FreeBASIC}}==

<lang freebasic>' version 12-04-2017

' compile with: fbc -s gui

' Computer Graphics Tutorial (lodev.org), last example

#Define dist(a, b, c, d) Sqr(((a - c) * (a - c) + (b - d) * (b - d)))

Const As ULong w = 256

Const As ULong h = 256

ScreenRes w, h, 24

WindowTitle ("Plasma effect")

Dim As ULong x, y

Dim As UByte c

Dim As Double time_, value

Do

time_ += .99

ScreenLock

For x = 0 To w -1

For y = 0 To h -1

value = Sin(dist(x + time_, y, 128, 128) / 8) _

+ Sin(dist(x, y, 64, 64) / 8) _

+ Sin(dist(x, y + time_ / 7, 192, 64) / 7) _

+ Sin(dist(x, y, 192, 100) / 8) + 4

' c = Int(value) * 32

c = int(value * 32)

PSet(x, y), RGB(c, c * 2, 255 - c)

Next

Next

ScreenUnLock

Sleep 1

If Inkey <> "" Or Inkey = Chr(255) + "k" Then

End

End If

Loop</lang>