Plasma Studies

[bplus]

The real study begins in late Jan 2020 with Plasmatic:

Code: (Select All)

_Title "Plasmatic  press spacebar for new coloring set" ' b+ 2020-01-20 translated and modified from SmallBASIC
'Plasma Magnifico - updated 2015-11-26 for Android
'This program creates a plasma surface, which looks oily or silky.

Const xmax = 800, ymax = 600
Type xy
    x As Single
    y As Single
    dx As Single
    dy As Single
End Type
Screen _NewImage(xmax, ymax, 32)
_ScreenMove 300, 40

Dim c(360) As _Unsigned Long, p(6) As xy, f(6)
restart:
r = Rnd: g = Rnd: b = Rnd: i = 0
For n = 1 To 5
    r1 = r: g1 = g: b1 = b
    Do: r = Rnd: Loop Until Abs(r - r1) > .2
    Do: g = Rnd: Loop Until Abs(g - g1) > .2
    Do: b = Rnd: Loop Until Abs(g - g1) > .2
    For m = 0 To 17: m1 = 17 - m
        f1 = (m * r) / 18: f2 = (m * g) / 18: f3 = (m * b) / 18: c(i) = rgbf(f1, f2, f3): i = i + 1
    Next
    For m = 0 To 17: m1 = 17 - m
        f1 = (m + m1 * r) / 18: f2 = (m + m1 * g) / 18: f3 = (m + m1 * b) / 18: c(i) = rgbf(f1, f2, f3): i = i + 1
    Next
    For m = 0 To 17: m1 = 17 - m
        f1 = (m1 + m * r) / 18: f2 = (m1 + m * g) / 18: f3 = (m1 + m * b) / 18: c(i) = rgbf(f1, f2, f3): i = i + 1
    Next
    For m = 0 To 17: m1 = 17 - m
        f1 = (m1 * r) / 18: f2 = (m1 * g) / 18: f3 = (m1 * b) / 18: c(i) = rgbf(f1, f2, f3): i = i + 1
    Next
Next

For n = 0 To 5
    p(n).x = Rnd * xmax: p(n).y = Rnd * ymax: p(n).dx = Rnd * 2 - 1: p(n).dy = Rnd * 2 - 1
    f(n) = Rnd * .1
Next

While _KeyDown(27) = 0
    If InKey$ = " " Then GoTo restart
    For i = 0 To 5
        p(i).x = p(i).x + p(i).dx
        If p(i).x > xmax Or p(i).x < 0 Then p(i).dx = -p(i).dx
        p(i).y = p(i).y + p(i).dy
        If p(i).y > ymax Or p(i).y < 0 Then p(i).dy = -p(i).dy
    Next
    For y = 0 To ymax - 1 Step 2
        For x = 0 To xmax - 1 Step 2
            d = 0
            For n = 0 To 5
                dx = x - p(n).x: dy = y - p(n).y
                k = Sqr(dx * dx + dy * dy)
                d = d + (Sin(k * f(n)) + 1) / 2
            Next n: d = d * 60
            Line (x, y)-Step(2, 2), c(d), BF
        Next
    Next
    _Display
    _Limit 100
Wend

Function rgbf~& (n1, n2, n3)
    rgbf~& = _RGB32(n1 * 255, n2 * 255, n3 * 255)
End Function