09-13-2025, 09:39 PM
And due to the OVERWHELMING interest in this thread, I decided to add 3 levels!
Code: (Select All)
_Title "Pete's Mini Space Invaders"
Width 40, 20: _Font 16
Type invaders
RenewVars As Integer
Level As Integer
Direction As Integer
TopRow As Integer
RowHeight As Integer
BaseLine As Integer
TrailColumn As Integer
MissileSpeed As Single
AlienSpeed As Single
HomeBase As Integer
BaseAction As Integer
TrailRow As Integer
LtColReduce As Integer
RtColReduce As Integer
z1 As Single
z2 As Single
z3 As Single
yfire As Integer
xfire As Integer
ybomb As Integer
xbomb As Integer
BombSpeed As Single
BombFreq As Single
Outcome As Integer
Score As _Integer64
Array As String
End Type
Dim si As invaders: ReDim a$(4)
Do
Levels si, a$()
Do
ScoreKeeper si
If si.yfire <> 0 And Abs(si.z2 - Timer) > si.MissileSpeed Then MissileAction si, a$(): If si.Outcome Then Exit Do
If Abs(si.z1 - Timer) > si.AlienSpeed Then
MoveAliens si, a$(): If si.Outcome Then Exit Do
End If
If Abs(si.z3 - Timer) > si.BombFreq Or si.ybomb And Abs(si.z3 - Timer) > si.BombSpeed Then
AlienBomb si, a$(): If si.Outcome Then Exit Do
End If
KeyBoard si
If si.BaseAction Then BaseAction si
If si.RenewVars Then si.RenewVars = 0
Loop
If si.Level = 3 And si.Outcome = 1 Then si.Outcome = 2 ' Winner!
If si.Outcome <> 1 Then
Finish si, a$() ' Loser!
Else
View Print 2 To _Height - 1: Cls 2: View Print: _Delay 1.5 ' CLear any remaining bombs or missiles.
End If
Loop
Sub Levels (si As invaders, a$())
si.RenewVars = 1
si.Outcome = 0
si.LtColReduce = 0
si.RtColReduce = 0
si.Direction = 1
si.TopRow = 4
si.RowHeight = 5
si.BaseLine = _Height
si.MissileSpeed = .04
si.HomeBase = _Width \ 2
si.Level = si.Level + 1
Select Case si.Level
Case 1
si.Array = "A A A A A A A A A"
si.AlienSpeed = .325
si.BombSpeed = .125
si.BombFreq = 1
Case 2
si.Array = "A A A A A A A A A A"
si.AlienSpeed = .35
si.BombSpeed = .1
si.BombFreq = .85
Case 3
si.Array = "A A A A A A A A A A A"
si.AlienSpeed = .375
si.BombSpeed = .075
si.BombFreq = .7
End Select
ReDim a$(4): For i = 0 To si.RowHeight - 1: a$(i) = si.Array: Next
si.TrailColumn = _Width \ 2 - Len(si.Array) \ 2
Cls
ScoreKeeper si
Refresh si, a$()
_Delay .5
Locate si.TopRow + si.RowHeight + 2: msg$ = "LEVEL 0" + LTrim$(Str$(si.Level)): CenterX msg$: _Delay 2.5
Locate si.TopRow + si.RowHeight + 2, 1: EraseRow
_Delay .5
End Sub
Sub CenterX (msg$)
Locate , _Width \ 2 - Len(msg$) \ 2: Print msg$;
End Sub
Sub EraseRow
Locate , 1: Print Space$(_Width);
End Sub
Sub ScoreKeeper (si As invaders)
info$ = Space$(_Width)
x$ = " Altitude:" + Str$(_Height * 1000 - (si.TopRow - 1 + si.RowHeight) * 1000) + " Ft Score:" + Str$(si.Score)
i = _Width / 2 - Len(x$) / 2
Mid$(info$, i) = x$
Locate 1, 1: Print info$;
End Sub
Sub KeyBoard (si As invaders)
Static restrict
If RenewVars Then restrict = 0
Select Case _KeyHit
Case 19200: If si.HomeBase > 1 And restrict = 0 Then si.HomeBase = si.HomeBase - 1: restrict = 1: si.BaseAction = -1
Case 19712: If si.HomeBase < _Width And restrict = 0 Then si.HomeBase = si.HomeBase + 1: restrict = 1: si.BaseAction = -1
Case -19200, -19712: restrict = 0: _KeyClear: si.BaseAction = 0
Case 32: If si.yfire = 0 Then si.BaseAction = 1
End Select
End Sub
Sub MissileAction (si As invaders, a$())
si.z2 = Timer
If Screen(si.yfire, si.xfire) = 24 Then Locate si.yfire, si.xfire: Print " ";
si.yfire = si.yfire - 1
If Screen(si.yfire, si.xfire) = 65 Then
RowCheck = 0: si.LtColReduce = 0: si.RtColReduce = 0: si.Score = si.Score + 625
Locate si.yfire, si.xfire: Print Chr$(15);: _Delay .1: Locate si.yfire, si.xfire: Print " ";
Mid$(a$(si.yfire - si.TopRow), si.xfire - si.TrailColumn + 1, 1) = " ": si.yfire = 0: Sound 1000, .5
For i = 4 To 0 Step -1
If Len(LTrim$(a$(i))) And RowCheck = 0 Then si.RowHeight = i + 1: RowCheck = 1
If Len(RTrim$(a$(i))) > si.RtColReduce Then si.RtColReduce = Len(RTrim$(a$(i)))
If Len(LTrim$(a$(i))) > si.LtColReduce Then si.LtColReduce = Len(LTrim$(a$(i)))
Next
si.RtColReduce = Len(si.Array) - si.RtColReduce: si.LtColReduce = Len(si.Array) - si.LtColReduce
If LTrim$(a$(0) + a$(1) + a$(2) + a$(3) + a$(4)) = "" Then
si.Outcome = 1
Else
Refresh si, a$()
End If
Else
If si.yfire < si.TrailRow Then si.yfire = 0 Else Locate si.yfire, si.xfire: Print Chr$(24);
End If
End Sub
Sub MoveAliens (si As invaders, a$())
si.z1 = Timer
If si.TopRow - 1 + si.RowHeight = si.BaseLine Then
si.Outcome = -1
Else
If si.TrailColumn + Len(si.Array) - si.RtColReduce > _Width And si.Direction = 1 Or si.TrailColumn = 1 - si.LtColReduce And si.Direction = -1 Then
si.Direction = -si.Direction: si.TopRow = si.TopRow + 1: si.AlienSpeed = si.AlienSpeed - .0225
If si.AlienSpeed < .1 Then si.AlienSpeed = .1: si.MissileSpeed = .025
Else
si.TrailColumn = si.TrailColumn + si.Direction
End If
Refresh si, a$()
Sound 500, .1
End If
End Sub
Sub AlienBomb (si As invaders, a$())
si.z3 = Timer
If si.TopRow + si.RowHeight < _Height - 3 Then
If si.ybomb = 0 Then ' Designate alien ship.
i = si.RowHeight - 1
k = Int(Rnd * (Len(si.Array) \ 2 + 1)) * 2 + 1
Do
For j = 1 To Len(si.Array)
If Mid$(a$(i), k, 1) = "A" Then
g = k: row = i: Exit Do
Else
For h = i To 0 Step -1
If Mid$(a$(h), k, 1) = "A" Then g = k: row = h: Exit Do
Next
End If
k = k + 2: If k > Len(a$(i)) Then k = 1
Next
Exit Do
Loop
si.ybomb = row + si.TopRow + 1
si.xbomb = si.TrailColumn - 1 + g
Locate si.ybomb - 1, si.xbomb: Color 4: Print "A";: Color 7: Sound 200, 1
Else
Locate si.ybomb, si.xbomb: Print " ";
If si.ybomb = _Height Then
si.ybomb = 0
Else
si.ybomb = si.ybomb + 1
If Screen(si.ybomb, si.xbomb) = 234 Then
Locate si.ybomb, si.xbomb: Color 4, 0: Print Chr$(236);: _Delay .15: Color 7, 0
Locate si.ybomb, si.xbomb
si.Outcome = -2
Else
Locate si.ybomb, si.xbomb: Print Chr$(249);
End If
End If
End If
End If
End Sub
Sub Refresh (si As invaders, a$())
si.TrailRow = 0
View Print si.TopRow - 1 To si.TopRow + si.RowHeight - 1: Cls 2
For i = 0 To si.RowHeight - 1
Locate si.TopRow + i, si.TrailColumn + si.LtColReduce
Print RTrim$(Mid$(a$(i), si.LtColReduce + 1));
If Len(LTrim$(a$(i))) And si.TrailRow = 0 Then si.TrailRow = si.TopRow + i
Next
View Print
If si.HomeBase Then Locate _Height, si.HomeBase: Print Chr$(234);
End Sub
Sub BaseAction (si As invaders)
Select Case si.BaseAction
Case -1
Locate _Height, 1: Print Space$(_Width);
Locate _Height, si.HomeBase: Print Chr$(234);
Case 1
si.yfire = _Height: si.xfire = si.HomeBase
End Select
si.BaseAction = 0
End Sub
Sub AlienBlitz (si As invaders, a$())
Cls: si.HomeBase = 0
ScoreKeeper si
Do
si.TopRow = si.TopRow + 1
Refresh si, a$()
Sound 500, .1: _Delay .1
Loop Until si.TopRow + si.RowHeight > _Height
Sound 200, 1
End Sub
Sub Finish (si As invaders, a$())
ScoreKeeper si
msg$ = "GAME OVER - "
Select Case si.Outcome
Case -2: msg$ = msg$ + "YOU LOST!": AlienBlitz si, a$()
Case -1: msg$ = msg$ + "YOU LOST!"
Case 2: msg$ = msg$ + "YOU WON!"
End Select
Locate 3, _Width / 2 - Len(x$) / 2: CenterX msg$
msg$ = "Replay? Y/N": Locate 5: CenterX msg$
Do
_Limit 10
b$ = InKey$
Select Case UCase$(b$)
Case "Y", Chr$(13): Cls: Run
Case "N", Chr$(27)
_Delay .5: msg$ = "Bye!"
Locate 7: CenterX msg$
_Delay 1.5: System
End Select
Loop
End Sub