While "True"
BOXES = 4 ' number of boxes per piece
BWIDTH = 25 ' box width in pixels
XOFFSET = 40 ' Screen X offset in pixels of where the board starts
YOFFSET = 40 ' Screen Y offset in pixels of where the board starts
CWIDTH = 10 ' Canvas Width, in number of boxes
CHEIGHT = 20 ' Canvas Height, in number of boxes.
STARTDELAY = 800
ENDDELAY = 175
PREVIEW_xpos = 13
PREVIEW_ypos = 2
CreatePiece() ' in: template ret: h
nextPiece = h
DrawPreviewPiece()
h = thisPiece
ypos = 0
done = 0
xpos = 3 ' always drop from column 3
CheckStop() ' in: ypos, xpos, h ret: done
If done = 1 Then
ypos = ypos - 1
MovePiece() 'in: ypos, xpos, h
end = 1
EndIf
yposdelta = 0
While done = 0 Or yposdelta > 0
MovePiece() 'in: ypos, xpos, h
' Delay, but break if the delay get set to 0 if the piece gets dropped
delayIndex = delay
While delayIndex > 0 And delay > 0
Program.Delay(10)
delayIndex = delayIndex - 10
EndWhile
If yposdelta > 0 Then
yposdelta = yposdelta - 1 ' used to create freespin, when the piece is rotated
Else
ypos = ypos + 1 ' otherwise, move the piece down.
EndIf
' Check if the piece should stop.
CheckStop() ' in: ypos, xpos, h ret: done
EndWhile
EndWhile
EndSub
Sub HandleKey
' Stop game
If GraphicsWindow.LastKey = "Escape" Then
Program.End()
EndIf
' Move piece left
If GraphicsWindow.LastKey = "Left" Then
moveDirection = -1
ValidateMove() ' in: ypos, xpos, h, moveDirection ret: invalidMove = 1 or -1 or 2 if move is invalid, otherwise 0
If invalidMove = 0 Then
xpos = xpos + moveDirection
EndIf
MovePiece() 'in: ypos, xpos, h
EndIf
' Move piece right
If GraphicsWindow.LastKey = "Right" Then
moveDirection = 1
ValidateMove() ' in: ypos, xpos, h, moveDirection ret: invalidMove = 1 or -1 or 2 if move is invalid, otherwise 0
If invalidMove = 0 Then
xpos = xpos + moveDirection
EndIf
MovePiece() 'in: ypos, xpos, h
EndIf
' Move piece down
If GraphicsWindow.LastKey = "Down" or GraphicsWindow.LastKey = "Space" Then
delay = 0
EndIf
' Rotate piece
If GraphicsWindow.LastKey = "Up" Then
basetemplate = Array.GetValue(h, -1) ' Array.GetValue(h, -1) = the template name
template = "temptemplate"
rotation = "CW"
CopyPiece() 'in basetemplate, template, rotation
Array.SetValue(h, -1, template) ' Array.GetValue(h, -1) = the template name
moveDirection = 0
ValidateMove() ' in: ypos, xpos, h, moveDirection ret: invalidMove = 1 or -1 or 2 if move is invalid, otherwise 0
' See if it can be moved so that it will rotate.
xposbk = xpos
yposdelta = 0
While yposdelta = 0 And Math.Abs(xposbk - xpos) < 3 ' move up to 3 times only
' if the rotation move worked, copy the temp to "rotatedtemplate" and use that from now on
If invalidMove = 0 Then
basetemplate = template
template = "rotatedtemplate"
Array.SetValue(h, -1, template) ' Array.GetValue(h, -1) = the template name
rotation = "COPY"
CopyPiece() 'in basetemplate, template, rotation
yposdelta = 1 ' Don't move down if we rotate
MovePiece() 'in: ypos, xpos, h
ElseIf invalidMove = 2 Then
' Don't support shifting piece when hitting another piece to the right or left.
xpos = 99 ' exit the loop
Else
' if the rotated piece can't be placed, move it left or right and try again.
xpos = xpos - invalidMove
ValidateMove() ' in: ypos, xpos, h, moveDirection ret: invalidMove = 1 or -1 or 2 if move is invalid, otherwise 0
EndIf
EndWhile
If invalidMove <> 0 Then
xpos = xposbk
Array.SetValue(h, -1, basetemplate) ' Array.GetValue(h, -1) = the template name
template = ""
EndIf
EndIf
EndSub
Sub DrawPreviewPiece
xpos = PREVIEW_xpos
ypos = PREVIEW_ypos
h = nextPiece
XOFFSETBK = XOFFSET
YOFFSETBK = YOFFSET
XOFFSET = XOFFSET + Array.GetValue(Array.GetValue(h, -1), "pviewx") ' Array.GetValue(h, -1) = the template name
YOFFSET = YOFFSET + Array.GetValue(Array.GetValue(h, -1), "pviewy") ' Array.GetValue(h, -1) = the template name
MovePiece() 'in: ypos, xpos, h
XOFFSET = XOFFSETBK
YOFFSET = YOFFSETBK
EndSub
' creates template that's a rotated basetemplate
Sub CopyPiece 'in basetemplate, template, rotation
L = Array.GetValue(basetemplate, "dim")
If rotation = "CW" Then
For i = 0 to BOXES - 1 ' x' = y y' = L - 1 - x
v = Array.GetValue(basetemplate, i)
'x = Math.Floor(v/10)
'y = Math.Remainder(v, 10)
' new x and y
x = (Math.Remainder(v, 10))
y = (L - 1 - Math.Floor(v/10))
Array.SetValue(template, i, x * 10 + y)
EndFor
' Count-Cockwise is not currently used
ElseIf rotation = "CCW" Then
For i = 0 to BOXES - 1 ' x' = L - 1 - y y' = x
v = Array.GetValue(basetemplate, i)
'x = Math.Floor(v/10)
'y = Math.Remainder(v, 10)
' new x and y
x = (L - 1 - Math.Remainder(v, 10))
y = Math.Floor(v/10)
Array.SetValue(template, i, x * 10 + y)
EndFor
ElseIf rotation = "COPY" Then
For i = 0 to BOXES - 1
Array.SetValue(template, i, Array.GetValue(basetemplate, i))
EndFor
Else
GraphicsWindow.ShowMessage("invalid parameter", "Error")
Program.End()
EndIf
' Copy the remain properties from basetemplate to template.
Array.SetValue(template, "color", Array.GetValue(basetemplate, "color"))
Array.SetValue(template, "dim", Array.GetValue(basetemplate, "dim"))
Array.SetValue(template, "pviewx", Array.GetValue(basetemplate, "pviewx"))
Array.SetValue(template, "pviewy", Array.GetValue(basetemplate, "pviewy"))
EndSub
Sub CreatePiece ' in: template ret: h
' Create a new handle, representing an arrayName, that will represent the piece
hcount = hcount + 1
h = Text.Append("piece", hcount)
Array.SetValue(h, -1, template) ' Array.GetValue(h, -1) = the template name
For i = 0 to BOXES - 1
s = Shapes.AddRectangle(BWIDTH, BWIDTH)
Shapes.Move(s, -BWIDTH, -BWIDTH) ' move off screen
Array.SetValue(h, i, s)
EndFor
EndSub
Sub MovePiece 'in: ypos, xpos, h. ypos/xpos is 0-19, representing the top/left box coordinate of the piece on the canvas. h returned by CreatePiece
For i = 0 to BOXES - 1
v = Array.GetValue(Array.GetValue(h, -1), i) ' Array.GetValue(h, -1) = the template name
x = Math.Floor(v/10)
y = Math.Remainder(v, 10)
' Array.GetValue(h, i) = box for piece h.
' xpos/ypos = are topleft of shape. x/y is the box offset within the shape.
Shapes.Move(Array.GetValue(h, i), XOFFSET + xpos * BWIDTH + x * BWIDTH, YOFFSET + ypos * BWIDTH + y * BWIDTH)
EndFor
EndSub
Sub ValidateMove ' in: ypos, xpos, h, moveDirection ret: invalidMove = 1 or -1 or 2 if move is invalid, otherwise 0
i = 0
invalidMove = 0
While i < BOXES
v = Array.GetValue(Array.GetValue(h, -1), i) ' Array.GetValue(h, -1) = the template name
'x/y is the box offset within the shape.
x = Math.Floor(v/10)
y = Math.Remainder(v, 10)
If (x + xpos + moveDirection) < 0 Then
invalidMove = -1
i = BOXES ' force getting out of the loop
EndIf
If (x + xpos + moveDirection) >= CWIDTH Then
invalidMove = 1
i = BOXES ' force getting out of the loop
EndIf
If Array.GetValue("c", (x + xpos + moveDirection) + (y + ypos) * CWIDTH) <> "." Then
invalidMove = 2
i = BOXES ' force getting out of the loop
EndIf
i = i + 1
EndWhile
EndSub
Sub CheckStop ' in: ypos, xpos, h ret: done
done = 0
i = 0
While i < BOXES
v = Array.GetValue(Array.GetValue(h, -1), i) ' Array.GetValue(h, -1) = the template name
'x/y is the box offset within the shape.
x = Math.Floor(v/10)
y = Math.Remainder(v, 10)
If y + ypos > CHEIGHT Or Array.GetValue("c", (x + xpos) + (y + ypos) * CWIDTH) <> "." Then
done = 1
i = BOXES ' force getting out of the loop
EndIf
i = i + 1
EndWhile
' If we need to stop the piece, move the box handles to the canvas
If done = 1 Then
For i = 0 to BOXES - 1
v = Array.GetValue(Array.GetValue(h, -1), i) ' Array.GetValue(h, -1) = the template name
'x = Math.Floor(v/10)
'y = Math.Remainder(v, 10)
Array.SetValue("c", (Math.Floor(v/10) + xpos) + (Math.Remainder(v, 10) + ypos - 1) * CWIDTH, Array.GetValue(h, i))
EndFor
' 1 points for every piece successfully dropped
score = score + 1
PrintScore()
' Delete clared lines
DeleteLines()
EndIf
EndSub
Sub DeleteLines
linesCleared = 0
' Iterate over each row, starting from the bottom
For y = CHEIGHT - 1 to 0 Step -1
' Check to see if the whole row is filled
x = CWIDTH
While x = CWIDTH
x = 0
While x < CWIDTH
piece = Array.GetValue("c", x + y * CWIDTH)
If piece = "." then
x = CWIDTH
EndIf
x = x + 1
EndWhile
' if non of them were empty (i.e "."), then remove the line.
If x = CWIDTH Then
' Delete the line
For x1 = 0 to CWIDTH - 1
Shapes.Remove(Array.GetValue("c", x1 + y * CWIDTH))
EndFor
linesCleared = linesCleared + 1
' Move everything else down one.
For y1 = y To 1 Step -1
For x1 = 0 to CWIDTH - 1
piece = Array.GetValue("c", x1 + (y1 - 1) * CWIDTH)
Array.SetValue("c", x1 + y1 * CWIDTH, piece)
Shapes.Move(piece, Shapes.GetLeft(piece), Shapes.GetTop(piece) + BWIDTH)
EndFor
EndFor
EndIf
EndWhile
EndFor
If linesCleared > 0 Then
score = score + 100 * Math.Round(linesCleared * 2.15 - 1)
PrintScore()
EndIf
EndSub
Program.Delay(200)
GraphicsWindow.PenWidth = 1
GraphicsWindow.PenColor = "Pink"
For x = 0 To CWIDTH-1
For y = 0 To CHEIGHT-1
Array.SetValue("c", x + y * CWIDTH, ".") ' "." indicates spot is free
GraphicsWindow.DrawRectangle(XOFFSET + x * BWIDTH, YOFFSET + y * BWIDTH, BWIDTH, BWIDTH)
EndFor
EndFor
GraphicsWindow.PenColor = "Black"
GraphicsWindow.BrushColor = "Pink"
x = XOFFSET + PREVIEW_xpos * BWIDTH - BWIDTH
y = YOFFSET + PREVIEW_ypos * BWIDTH - BWIDTH
GraphicsWindow.FillRectangle(x, y, BWIDTH * 5, BWIDTH * 6)
GraphicsWindow.DrawRectangle(x, y, BWIDTH * 5, BWIDTH * 6)
GraphicsWindow.FillRectangle(x - 20, y + 190, 310, 170)
GraphicsWindow.DrawRectangle(x - 20, y + 190, 310, 170)
GraphicsWindow.BrushColor = "Black"
GraphicsWindow.FontItalic = "False"
GraphicsWindow.FontName = "Comic Sans MS"
GraphicsWindow.FontSize = 16
GraphicsWindow.DrawText(x, y + 200, "Game control keys:")
GraphicsWindow.DrawText(x + 25, y + 220, "Left Arrow = Move piece left")
GraphicsWindow.DrawText(x + 25, y + 240, "Right Arrow = Move piece right")
GraphicsWindow.DrawText(x + 25, y + 260, "Up Arrow = Rotate piece")
GraphicsWindow.DrawText(x + 25, y + 280, "Down Arrow = Drop piece")
GraphicsWindow.DrawText(x, y + 320, "Press to stop game")
Program.Delay(200) ' without this delay, the above text will use the fontsize of the score
GraphicsWindow.BrushColor = "Black"
GraphicsWindow.FontName = "Georgia"
GraphicsWindow.FontItalic = "True"
GraphicsWindow.FontSize = 36
GraphicsWindow.DrawText(x - 20, y + 400, "Small Basic Tetris")
Program.Delay(200) ' without this delay, the above text will use the fontsize of the score
GraphicsWindow.FontSize = 16
GraphicsWindow.DrawText(x - 20, y + 440, "ver.0.1")
Program.Delay(200) ' without this delay, the above text will use the fontsize of the score
score = 0
PrintScore()
EndSub
Sub SetupTemplates
' each piece has 4 boxes.
' the index of each entry within a piece represents the box number (1-4)
' the value of each entry represents to box zero-based box coordinate within the piece: tens place is x, ones place y
Program Listing: TETRIS