Const fade = 5 'speed by which our trail disappears

Randomize Timer

Screen _NewImage(640, 480, 32)

background = _NewImage(640, 480, 32)

movescreen = _NewImage(640, 480, 32)



'let's draw a nice background of junk

_Dest background

Cls , &HFFF000F0&&

For i = 1 To 20

    Line (Rnd * 100, Rnd * 100)-(Rnd * 700, Rnd * 500), _RGB32(Rnd * 256, Rnd * 256, Rnd * 256), BF

Next



'then let's swap to the movescreen and work

_Dest movescreen

Do

    Cls , 0, 0

    While _MouseInput: Wend

    mx = _MouseX: my = _MouseY

    'fade the movescreen over time

    FadeScreen movescreen, fade

    'update the red box position that chases the mouse slowly

    x = x + Sgn(mx - x): y = y + Sgn(my - y)

    'draw the solid box which chases after the mouse

    Line (x, y)-Step(50, 50), &HFFFF0000, BF

    'put the parts on the screen

    _PutImage , background, 0

    _PutImage , movescreen, 0

    _Limit 60

    _Display

Loop



Sub FadeScreen (s, faderate)

    Dim m As _MEM, o As _Offset

    m = _MemImage(s)

    Dim p As _Unsigned Long

    Do Until o >= m.SIZE

        _MemGet m, m.OFFSET + o, p

        If p <> 0 Then 'fade the point down to 0 (transparent)

            r = _Red32(p) - faderate: If r < 0 Then r = 0

            g = _Green32(p) - faderate: If g < 0 Then g = 0

            b = _Blue32(p) - faderate: If b < 0 Then b = 0

            a = _Alpha32(p) - faderate: If a < 0 Then a = 0

            _MemPut m, m.OFFSET + o, _RGBA32(r, g, b, a) As _UNSIGNED LONG

        End If

        o = o + 4

    Loop

    _MemFree m

End Sub

(01-01-2025, 06:20 AM)bplus Wrote: +1 Oh man! great Steve, thanks!

Cool and cute and brief, I will study, I see you are using Mem's.