Small Basic Sample: Snake
Code
Initialize()
While (GameState <> "")
DoGameLoop()
EndWhile
Program.End()
Sub Initialize
InitializeVariables()
InitializeScreen()
EndSub
Sub InitializeVariables
Array.SetValue("DeltaX","North",0)
Array.SetValue("DeltaX","East",1)
Array.SetValue("DeltaX","South",0)
Array.SetValue("DeltaX","West",-1)
Array.SetValue("DeltaY","North",-1)
Array.SetValue("DeltaY","East",0)
Array.SetValue("DeltaY","South",1)
Array.SetValue("DeltaY","West",0)
Array.SetValue("NorthFlag","North",1)
Array.SetValue("NorthFlag","East",0)
Array.SetValue("NorthFlag","South",0)
Array.SetValue("NorthFlag","West",0)
Array.SetValue("SouthFlag","North",0)
Array.SetValue("SouthFlag","East",0)
Array.SetValue("SouthFlag","South",1)
Array.SetValue("SouthFlag","West",0)
Array.SetValue("EastFlag","North",0)
Array.SetValue("EastFlag","East",1)
Array.SetValue("EastFlag","South",0)
Array.SetValue("EastFlag","West",0)
Array.SetValue("WestFlag","North",0)
Array.SetValue("WestFlag","East",0)
Array.SetValue("WestFlag","South",0)
Array.SetValue("WestFlag","West",1)
Array.SetValue("DirectionInput","N","North")
Array.SetValue("DirectionInput","E","East")
Array.SetValue("DirectionInput","S","South")
Array.SetValue("DirectionInput","W","West")
GameDelay = 100
Score = 0
HighScore = 0
GameState = "TitleScreen"
ScreenDirty = 1
CurrentDirectory = Text.GetSubText(File.GetSettingsFilePath(),0,Text.GetLength(File.GetSettingsFilePath())-26)
EndSub
Sub InitializeScreen
GraphicsWindow.Show()
GraphicsWindow.Width = 640
GraphicsWindow.Height = 480
GraphicsWindow.KeyDown = HandleKeyPress
EndSub
Sub HandleTitleScreenKeyPress
Key = GraphicsWindow.LastKey
If (Key = "Escape") Then
GameState=""
Else
If (Key="F2") Then
GameState = "Play"
ScreenDirty = 1
Else
If (Key="F1") Then
GameState = "Instructions"
ScreenDirty = 1
EndIf
EndIf
EndIf
EndSub
Sub HandleInstructionsKeyPress
Key = GraphicsWindow.LastKey
If (Key = "Escape") Then
GameState = "TitleScreen"
ScreenDirty = 1
EndIf
EndSub
Sub HandlePlayKeyPress
Key = GraphicsWindow.LastKey
If (Key = "Left") Then
DirectionInput = DirectionInput + "W"
Else
If (Key = "Right") Then
DirectionInput = DirectionInput + "E"
Else
If (Key = "Up") Then
DirectionInput = DirectionInput + "N"
Else
If (Key = "Down") Then
DirectionInput = DirectionInput + "S"
EndIf
EndIf
EndIf
EndIf
EndSub
Sub HandleGameOverKeyPress
Key = GraphicsWindow.LastKey
If (Key = "Escape") Then
GameState=""
Else
If (Key="F2") Then
GameState = "Play"
ScreenDirty = 1
Else
If (Key="F1") Then
GameState = "Instructions"
ScreenDirty = 1
EndIf
EndIf
EndIf
EndSub
Sub HandleKeyPress
If (GameState="TitleScreen") Then
HandleTitleScreenKeyPress()
Else
If (GameState="Instructions") Then
HandleInstructionsKeyPress()
Else
If (GameState="Play") Then
HandlePlayKeyPress()
Else
If (GameState="GameOver") Then
HandleGameOverKeyPress()
Else
EndIf
EndIf
EndIf
EndIf
EndSub
Sub DoTitleScreenLoop
If (ScreenDirty = 1) Then
ScreenDirty = 0
GraphicsWindow.Clear()
GraphicsWindow.BrushColor = "#000000"
GraphicsWindow.FontSize = 32
GraphicsWindow.DrawText(0,0,"SBSnake!")
GraphicsWindow.FontSize = 16
GraphicsWindow.DrawText(0,64,"F1 for instructions")
GraphicsWindow.DrawText(0,80,"F2 for a new game")
GraphicsWindow.DrawText(0,96,"Escape to exit")
EndIf
EndSub
Sub DoInstructionLoop
If (ScreenDirty = 1) Then
ScreenDirty = 0
GraphicsWindow.Clear()
GraphicsWindow.BrushColor = "#000000"
GraphicsWindow.FontSize = 32
GraphicsWindow.DrawText(0,0,"How To Play SBSnake!")
GraphicsWindow.FontSize = 16
GraphicsWindow.DrawText(0,64,"Arrows to move snake.")
GraphicsWindow.DrawText(0,80,"Don't hit the walls; don't hit your tail.")
GraphicsWindow.DrawText(0,96,"Eat pellets to increase score.")
GraphicsWindow.DrawText(0,112,"Escape to return to main menu")
EndIf
EndSub
Sub AddPellet
PickPellet:
PelletX = Math.GetRandomNumber(40)-1
PelletY = Math.GetRandomNumber(30)-1
Color = GraphicsWindow.GetPixel(PelletX * 16 + 8, PelletY * 16 + 8)
If (Color = "#00FF00" Or Color="#FF0000") Then
Goto PickPellet
EndIf
GraphicsWindow.PenWidth = 0
GraphicsWindow.BrushColor = "#FF0000"
GraphicsWindow.FillRectangle(PelletX* 16+3, PelletY * 16+3,10,10)
EndSub
Sub DrawHead
GraphicsWindow.PenWidth = 0
GraphicsWindow.BrushColor = "#00FF00"
GraphicsWindow.FillRectangle(SnakeHeadX * 16+2, SnakeHeadY * 16+2,12,12)
If (Direction="South") Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+4, SnakeHeadY*16,8,4)
EndIf
If (Direction="North") Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+4, SnakeHeadY*16+12,8,4)
EndIf
If (Direction="East") Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16, SnakeHeadY*16+4,4,8)
EndIf
If (Direction="West") Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+12, SnakeHeadY*16+4,4,8)
EndIf
EndSub
Sub EraseHead
If (GraphicsWindow.GetPixel(SnakeHeadX*16+8,SnakeHeadY*16)="#00FF00") Then
NorthFlag = 1
Else
NorthFlag = Array.GetValue("NorthFlag",Direction)
EndIf
If (GraphicsWindow.GetPixel(SnakeHeadX*16+8,SnakeHeadY*16+15)="#00FF00") Then
SouthFlag = 1
Else
SouthFlag = Array.GetValue("SouthFlag",Direction)
EndIf
If (GraphicsWindow.GetPixel(SnakeHeadX*16,SnakeHeadY*16+8)="#00FF00") Then
WestFlag = 1
Else
WestFlag = Array.GetValue("WestFlag",Direction)
EndIf
If (GraphicsWindow.GetPixel(SnakeHeadX*16+15,SnakeHeadY*16+8)="#00FF00") Then
EastFlag = 1
Else
EastFlag = Array.GetValue("EastFlag",Direction)
EndIf
GraphicsWindow.BrushColor = "#FFFFFF"
GraphicsWindow.FillRectangle(SnakeHeadX * 16, SnakeHeadY*16,16,16)
GraphicsWindow.BrushColor = "#00FF00"
If (AtePellet = 1) Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+3, SnakeHeadY*16+3,10,10)
Else
GraphicsWindow.FillRectangle(SnakeHeadX * 16+4, SnakeHeadY*16+4,8,8)
EndIf
If (NorthFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+4, SnakeHeadY*16,8,4)
EndIf
If (SouthFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+4, SnakeHeadY*16+12,8,4)
EndIf
If (WestFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16, SnakeHeadY*16+4,4,8)
EndIf
If (EastFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeHeadX * 16+12, SnakeHeadY*16+4,4,8)
EndIf
EndSub
Sub EraseTail
If (GraphicsWindow.GetPixel(SnakeTailX*16+8,SnakeTailY*16)="#00FF00") Then
NorthFlag = 1
Else
NorthFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16+8,SnakeTailY*16+15)="#00FF00") Then
SouthFlag = 1
Else
SouthFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16,SnakeTailY*16+8)="#00FF00") Then
WestFlag = 1
Else
WestFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16+15,SnakeTailY*16+8)="#00FF00") Then
EastFlag = 1
Else
EastFlag = 0
EndIf
GraphicsWindow.BrushColor = "#FFFFFF"
GraphicsWindow.FillRectangle(SnakeTailX * 16, SnakeTailY*16,16,16)
If (NorthFlag = 1) Then
TailDirection = "North"
EndIf
If (SouthFlag = 1) Then
TailDirection = "South"
EndIf
If (EastFlag = 1) Then
TailDirection = "East"
EndIf
If (WestFlag = 1) Then
TailDirection = "West"
EndIf
SnakeTailX = SnakeTailX + Array.GetValue("DeltaX",TailDirection)
SnakeTailY = SnakeTailY + Array.GetValue("DeltaY",TailDirection)
If (GraphicsWindow.GetPixel(SnakeTailX*16+3,SnakeTailY*16+3)="#00FF00") Then
TailPellet = 1
Else
TailPellet = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16+8,SnakeTailY*16)="#00FF00") Then
NorthFlag = 1
Else
NorthFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16+8,SnakeTailY*16+15)="#00FF00") Then
SouthFlag = 1
Else
SouthFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16,SnakeTailY*16+8)="#00FF00") Then
WestFlag = 1
Else
WestFlag = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeTailX*16+15,SnakeTailY*16+8)="#00FF00") Then
EastFlag = 1
Else
EastFlag = 0
EndIf
If (TailDirection="North") Then
SouthFlag = 0
EndIf
If (TailDirection="South") Then
NorthFlag = 0
EndIf
If (TailDirection="East") Then
WestFlag = 0
EndIf
If (TailDirection="West") Then
EastFlag = 0
EndIf
GraphicsWindow.FillRectangle(SnakeTailX * 16, SnakeTailY*16,16,16)
GraphicsWindow.BrushColor = "#00FF00"
If (TailPellet = 1) Then
GraphicsWindow.FillRectangle(SnakeTailX * 16+3, SnakeTailY*16+3,10,10)
Else
GraphicsWindow.FillRectangle(SnakeTailX * 16+4, SnakeTailY*16+4,8,8)
EndIf
If (NorthFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeTailX * 16+4, SnakeTailY*16,8,4)
EndIf
If (SouthFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeTailX * 16+4, SnakeTailY*16+12,8,4)
EndIf
If (WestFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeTailX * 16, SnakeTailY*16+4,4,8)
EndIf
If (EastFlag = 1) Then
GraphicsWindow.FillRectangle(SnakeTailX * 16+12, SnakeTailY*16+4,4,8)
EndIf
EndSub
Sub ProcessDirectionInput
If (Text.GetLength(DirectionInput)>0) Then
Temp = Text.GetSubText(DirectionInput,1,1)
DirectionInput = Text.GetSubText(DirectionInput,1,Text.GetLength(DirectionInput)-1)
Direction = Array.GetValue("DirectionInput",Temp)
EndIf
EndSub
Sub StartGame
Direction=""
DirectionInput=""
SnakeLength = 1
SnakeMaximumLength = 4
SnakeHeadX = 20
SnakeHeadY = 15
SnakeTailX = 20
SnakeTailY = 15
AtePellet = 0
Score = 0
GraphicsWindow.Clear()
DrawHead()
AddPellet()
UpdateScore()
EndSub
Sub UpdateScore
GraphicsWindow.Title = "SBSnake - "+Score
EndSub
Sub DoPlayLoop
If (ScreenDirty = 1) Then
ScreenDirty = 0
StartGame()
Else
If (Direction <> "" Or DirectionInput<>"") Then
ProcessDirectionInput()
EraseHead()
SnakeHeadX = SnakeHeadX + Array.GetValue("DeltaX",Direction)
SnakeHeadY = SnakeHeadY + Array.GetValue("DeltaY",Direction)
If (SnakeHeadX<0 Or SnakeHeadX>39 Or SnakeHeadY < 0 Or SnakeHeadY > 29) Then
GameState = "GameOver"
ScreenDirty = 1
Else
If (GraphicsWindow.GetPixel(SnakeHeadX*16+8,SnakeHeadY*16+8)="#FF0000") Then
Score = Score + 1
UpdateScore()
AtePellet = 1
SnakeMaximumLength = SnakeMaximumLength + 2
AddPellet()
Else
AtePellet = 0
EndIf
If (GraphicsWindow.GetPixel(SnakeHeadX*16+8,SnakeHeadY*16+8)="#00FF00") Then
GameState = "GameOver"
DrawHead()
ScreenDirty = 1
Else
SnakeLength = SnakeLength + 1
DrawHead()
While (SnakeLength>SnakeMaximumLength)
EraseTail()
SnakeLength = SnakeLength - 1
EndWhile
Program.Delay(GameDelay)
EndIf
EndIf
EndIf
EndIf
EndSub
Sub DoGameOverLoop
If (ScreenDirty = 1) Then
ScreenDirty = 0
GraphicsWindow.BrushColor = "#000000"
GraphicsWindow.FontSize = 32
GraphicsWindow.DrawText(0,0,"Game Over!")
GraphicsWindow.FontSize = 16
GraphicsWindow.DrawText(0,64,"F1 for instructions")
GraphicsWindow.DrawText(0,80,"F2 for a new game")
GraphicsWindow.DrawText(0,96,"Escape to exit")
EndIf
EndSub
Sub DoGameLoop
If (GameState = "TitleScreen") Then
DoTitleScreenLoop()
Else
If (GameState = "Instructions") Then
DoInstructionLoop()
Else
If (GameState = "Play") Then
DoPlayLoop()
Else
If (GameState = "GameOver") Then
DoGameOverLoop()
EndIf
EndIf
EndIf
EndIf
EndSub
See Also
Other Languages