Option _Explicit

_Title "Bolt 2: click mouse around screen" ' b+ 2023-07-15  started as Bloom.bas

' 2023-07-16 rename to Bolt from Bloom and comment better and make more generic

' 2023-07-17 Bolts 2: move the bolt down the BoltLine by speed like a bullet.



' BoltLine: Imagine a line with a thickness at one end and a different thickness at then other.

' Colored like I imagine a Laser beam yellowish white core with bluish tinge around the edges.

' Now draw sections of that BoltLine according to the frames of display in main loop.

' This is a demo of that!



Const NBolts = 20 ' max number of Bolt slots available, just like bullet science

Const PulseLength = 100 ' length of light pulses as they travel down BoltLine



Type BoltType 'see NewBolt for description of these variables

    As Single x1, y1, r1, dx, dy, dr, d, frames, frame, active, speedX, speedY

End Type



Dim Shared Bolts(1 To NBolts) As BoltType

Dim mx, my, i, lpc, back



Randomize Timer

Screen _NewImage(1200, 700, 32)

_ScreenMove 50, 20

back = _NewImage(_Width, _Height, 32)

For i = 1 To 150

    Line (Rnd * _Width, Rnd * _Height)-Step(Rnd * 100, Rnd * 70), _RGB32(Rnd * 100, Rnd * 100, Rnd * 100), BF

Next i

_PutImage , 0, back

Do

    Cls

    _PutImage , back, 0

    DrawShip 600, 350, &HFF00CC66 ' bplus signature space ship, for rent 



    ' fire off some more bolts at the ship from the screen corners!

    If lpc = 0 Then

        If Rnd < .5 Then NewBolt 0, 0, 1, 600, 350, 10, 10

    ElseIf lpc = 30 Then

        If Rnd < .5 Then NewBolt _Width - 1, 0, 1, 600, 350, 20, 7

    ElseIf lpc = 60 Then

        If Rnd < .5 Then NewBolt _Width - 1, _Height - 1, 1, 600, 350, 30, 5

    ElseIf lpc = 90 Then

        If Rnd < .5 Then NewBolt 0, _Height - 1, 1, 600, 350, 50, 2

    End If

    lpc = (lpc + 1) Mod 120 ' loopscounter every 30 shoot from a corner



    While _MouseInput: Wend

    mx = _MouseX: my = _MouseY

    If _MouseButton(1) Then

        NewBolt 600, 340, 1, mx, my, 15, 20

        _Delay .1 ' wait a little for mouse release so 2 bolts aren't draw from 1 click

    End If

    For i = 1 To NBolts

        If Bolts(i).active Then DrawBolt (i) ' draws the bolts still active

    Next '                                    according to what frame they are on

    _Display

    _Limit 60

Loop Until _KeyDown(27)



Sub NewBolt (x1, y1, r1, x2, y2, r2, ppfSpeed) ' sets up for the DrawBolt Sub

    'x1, y1, r1 = location and radius at start of beam

    'x2, y2, r2 = target location and radius at beam end

    'ppfSpeed = how many pixels per frame in main loop  to transverse

    Dim i, ang

    For i = 1 To NBolts

        If Bolts(i).active = 0 Then

            Bolts(i).x1 = x1 ' start x, y, radius

            Bolts(i).y1 = y1

            Bolts(i).r1 = r1

            Bolts(i).active = 1 ' bolt is activated

            Bolts(i).dx = x2 - x1 ' drawing the bolt line and thickness

            Bolts(i).dy = y2 - y1 ' as it changes from x1, y1, r1 to x2, y2, r2

            Bolts(i).dr = r2 - r1

            Bolts(i).d = _Hypot(Bolts(i).dx, Bolts(i).dy) ' distance of the bolt line

            Bolts(i).frames = Int(Bolts(i).d / ppfSpeed) + 1 ' divide that distance by pulse = PulseLength

            Bolts(i).frame = 1 ' set the frame you are on to locate the pulse in drawing

            ang = _Atan2(y2 - y1, x2 - x1)

            Bolts(i).speedX = ppfSpeed * Cos(ang)

            Bolts(i).speedY = ppfSpeed * Sin(ang)

            Exit Sub

        End If

    Next

End Sub



Sub DrawBolt (idx) ' needs FCirc (Fill Circle) routine

    ' This sub draw a pulse of light on the BoltLine from .x1, .y1 on the way to .x2, .y2

    ' The start radius is .r1 and the end radius is .r2 and the pulse is thinned or thickened

    ' as it proceeds down the boltLine.



    'All this is setup in the NewBolt Sub and uses DIM Shared Bolts() as BoltType and Constants

    ' NBolts = max amount of activated Bolt "slots" available and PulseLength the length of

    ' BoltLine sections to draw in each frame.



    Dim i, x, y, d



    ' new lead position

    x = Bolts(idx).x1 + Bolts(idx).speedX * Bolts(idx).frame

    y = Bolts(idx).y1 + Bolts(idx).speedY * Bolts(idx).frame

    d = _Hypot(Bolts(idx).x1 - x, Bolts(idx).y1 - y)



    For i = d - PulseLength To d

        If i >= 0 Then

        FCirc Bolts(idx).x1 + i * Bolts(idx).dx / Bolts(idx).d, Bolts(idx).y1 + i * Bolts(idx).dy _

        / Bolts(idx).d, Bolts(idx).r1 + i * Bolts(idx).dr / Bolts(idx).d, &H10DDDDFF

        FCirc Bolts(idx).x1 + i * Bolts(idx).dx / Bolts(idx).d, Bolts(idx).y1 + i * Bolts(idx).dy _

        / Bolts(idx).d, .35 * Bolts(idx).r1 + i * .4 * Bolts(idx).dr / Bolts(idx).d, &HaaFFFFAA

        End If

    Next

    Bolts(idx).frame = Bolts(idx).frame + 1 ' update frame number

    If Bolts(idx).frame > Bolts(idx).frames Then Bolts(idx).active = 0 ' job done!

End Sub



Sub FCirc (CX As Integer, CY As Integer, R As Integer, C As _Unsigned Long)

    Dim Radius As Integer, RadiusError As Integer

    Dim X As Integer, Y As Integer

    Radius = Abs(R): RadiusError = -Radius: X = Radius: Y = 0

    If Radius = 0 Then PSet (CX, CY), C: Exit Sub

    Line (CX - X, CY)-(CX + X, CY), C, BF

    While X > Y

        RadiusError = RadiusError + Y * 2 + 1

        If RadiusError >= 0 Then

            If X <> Y + 1 Then

                Line (CX - Y, CY - X)-(CX + Y, CY - X), C, BF

                Line (CX - Y, CY + X)-(CX + Y, CY + X), C, BF

            End If

            X = X - 1

            RadiusError = RadiusError - X * 2

        End If

        Y = Y + 1

        Line (CX - X, CY - Y)-(CX + X, CY - Y), C, BF

        Line (CX - X, CY + Y)-(CX + X, CY + Y), C, BF

    Wend

End Sub



Sub DrawShip (x, y, colr As _Unsigned Long) 'needs FCirc and FEllipse subs

    Static ls ' tracks the last light position in string of lights

    Dim light As Long, r As Long, g As Long, b As Long

    r = _Red32(colr): g = _Green32(colr): b = _Blue32(colr)

    FEllipse x, y, 6, 15, _RGB32(r, g - PulseLength, b - 100)

    FEllipse x, y, 18, 11, _RGB32(r, g - 60, b - 50)

    FEllipse x, y, 30, 7, _RGB32(r, g, b)

    For light = 0 To 5

        FCirc x - 30 + 11 * light + ls, y, 1, _RGB32(ls * 50, ls * 50, ls * 50)

    Next

    ls = ls + 1

    If ls > 5 Then ls = 0

End Sub



Sub FEllipse (CX As Long, CY As Long, xr As Long, yr As Long, C As _Unsigned Long)

    If xr = 0 Or yr = 0 Then Exit Sub

    Dim h2 As _Integer64, w2 As _Integer64, h2w2 As _Integer64

    Dim x As Long, y As Long

    w2 = xr * xr: h2 = yr * yr: h2w2 = h2 * w2

    Line (CX - xr, CY)-(CX + xr, CY), C, BF

    Do While y < yr

        y = y + 1

        x = Sqr((h2w2 - y * y * w2) \ h2)

        Line (CX - x, CY + y)-(CX + x, CY + y), C, BF

        Line (CX - x, CY - y)-(CX + x, CY - y), C, BF

    Loop

End Sub

Quote:' But Mark how do we detect hits from lasers, OK added x, y, r to track the current location
' and radius of the laser bolt.

(07-21-2023, 03:00 AM)Dav Wrote: @bplus, you coding always amazes me.  Great stuff.

That image library by @RhoSigma is incredible!  Packed with filters.  

- Dav