Microsoft Small Basic

Program Listing: SNKBITE
' SNAKEBITE-SB
' by Davey~Wavey, v1 Nov. 2009
' Written for SmallBasic v0.7
'
' Inspired by the ZX81 game SNAKEBITE.
'
' Eat the snake by chewing off it's tail. Eat all tail segments to progress to next level.
' Watch out though, you may just make it angry!
'
' Use the cursor keys to move around. (You can press any other key to stop moving!)

' NOTE: If it crashes a lot, try commenting out the 'Sound.PlayChimes()' line. SB doesn't like sound!
'
' I've laid the code out so that all the normal routines used in a game are present. If you're
' learning to write your own game, a similar setup should work well for you. Have fun!

' set up the permanent loop (Q key terminates when on intro screen)
While 1=1

' initialise game environment
environment()

' show intro
introScreen()

While lives > 0
' INITIALISE LEVEL

' Next line won't play anything if we have already played the intro screen music!?!?!?!!!
' It also seems to cause the prog to crash more often when enabled.
'Sound.Play (progDir + "\muzak.mid")

levelConfig() ' level maps can be found at end of program listing below - have fun designing some
paintLevel()
snakeSetup()
playerSetup()


' MAIN LOOP
While (snakeSize > 2) And lives > 0

' if snake 'change direction' delay has expired, try to change snake direction
If snakeMoveDelay = 0 Then
snakeDirection() ' will only change direction at random times

moveSnake()
EndIf

' alternative method to check for key press - also delays movement of player
If playerMoveDelay = 0 Then
checkKeys()

movePlayer()

' Check for PLAYER COLLISIONS
playerCollisions()
EndIf



' ADJUST (or reset) DELAYS
' I admit this isn't the best way to do this.
' To get accurate speed, you should be calculating the
' frames-per-second and using that to slow various elements down.
If snakeMoveDelay > 0 Then
snakeMoveDelay = snakeMoveDelay-1
Else
snakeMoveDelay = level[thisLevel]["snakeDelay"]
EndIf

If playerMoveDelay > 0 Then
playerMoveDelay = playerMoveDelay-1
Else
playerMoveDelay = playerDelay
EndIf


' test snake length increase - NOT CURRENTLY USED
'If Mouse.IsLeftButtonDown="True" AND processing=0 Then
' addSegment()
'ElseIf Mouse.IsLeftButtonDown="False" And processing=1 Then
' mUp()
'EndIf

EndWhile ' main level (or lives) loop



' next line is irrellevant as the Sound.Play command above doesn't work!
'Sound.Stop (progDir + "\muzak.mid")



' if we still have some lives, then we must have eaten all the snake
If lives > 0 Then

moveSnake() ' update tail position since snake length just decreased

GraphicsWindow.ShowMessage("YEAH, YOU BEAT THIS SNAKE!!!", "WHOOPIE!")

' move to next level
thisLevel=thisLevel+1

' go back to level 1 if we've completed them all
If thisLevel>levels Then
thisLevel=1
EndIf

' increase player speed (by decreasing the delay) - player gets a slight advantage for each level cleared :-)
If playerDelay > 20 Then
playerDelay = playerDelay - 10
EndIf

GraphicsWindow.Clear()
EndIf


EndWhile ' lives > 0

' DEAD MEAT!

' next line doesn't work!
'Sound.Play (progDir + "\gameover.mid")

GraphicsWindow.ShowMessage("THAT PUNKY SNAKE BEAT YOU THIS TIME!!! You scored: "+score, "EATEN!!!")

' next line is irrellevant as the Play command above doesn't work!
'Sound.Stop (progDir + "\gameover.mid")

EndWhile





' =====================================================================
' =====================================================================
' ====================== S U B R O U T I N E S ==============================
' =====================================================================
' =====================================================================





Sub environment
' initialise the game environment

' progDir = Program.Directory + "\assets" ' this is used to locate the graphics and music used in the game
progDir = "http://smallbasic.com/drop/snakebite"

GraphicsWindow.Title = "~S~N~A~K~E~B~I~T~E~ v1 for SmallBasic by Davey~Wavey, Nov 2009"
GraphicsWindow.BackgroundColor = "Black"
GraphicsWindow.Width = 800 ' grass sprite is 128 x 128
GraphicsWindow.Height = 600 ' 4 x 128 plus status area
GraphicsWindow.Left = desktop.Width/2-(GraphicsWindow.Width/2) ' 800
GraphicsWindow.Top = desktop.Height/2-(GraphicsWindow.Height/2)-100 '50

gwTop = 18 ' set game window top offset
gwBottom = gwTop+(4*128)
gwLeft = (GraphicsWindow.Width/2)-(3*128) ' set game window left offset
gwRight = gwLeft+(6*128)

' initialise game environment
thisLevel = 1
score = 0
lives = 5
playerDelay = 500 ' speed of player movement - lower value = faster player = easier (unless you go too fast!)
snakeMoveDelay = 0 ' this gets set by each level and is the speed of the snake - lower = faster

angrySnake = -1 ' a counter. if >0 it indicates that snake is angry (makes snake faster)
digestionDelay = 0 ' delay to prevent multiple tail pieces being eaten at once.
processing = 0 ' a flag used in sub processes to prevent multiple runs

player = "" ' blank player array
snake = "" ' blank snake array

'Timer.Interval = 2 ' set interval to check for key presses
'Timer.Tick = checkKeys

EndSub


' =====================================================================


Sub introScreen
' display the game intro screen and wait for Space to be pressed

GraphicsWindow.Clear()

' this Play command works, but then prevents any other music playing!?!?!
Sound.Play (progDir + "\intro.mid")

' show intro graphic
img = ImageList.LoadImage(progDir + "\titleScreen_800x600.jpg")
GraphicsWindow.DrawImage(img, 0,0 )

' wait for keypress
lastkey = ""
While lastkey <> "Space"
lastkey = GraphicsWindow.LastKey

If lastkey = "Q" Then
Program.End()
EndIf
EndWhile

Sound.Stop (progDir + "\intro.mid")
Program.Delay(500)
EndSub


' =====================================================================


Sub paintLevel
' draw the level objects at the start of each level


' create a black rectangle over the whole graphics window so we can create a fade effect after the level has been drawn
GraphicsWindow.BrushColor = "Black"
bbox = Shapes.AddRectangle( 800, 600 )
Shapes.SetOpacity (bbox, 100)


' draw dirt
img = ImageList.LoadImage(progDir + "\status_800x70.png")
For y = 0 to 600 Step 70
GraphicsWindow.DrawImage (img, 0, y)
EndFor


' draw the grass
img = ImageList.LoadImage(progDir + "\grass_128d.png")
For x = 0 To 5
For y = 0 To 3
GraphicsWindow.DrawImage (img, (x*128)+gwLeft, (y*128)+gwTop)
EndFor
EndFor


' draw the flowers
img = ImageList.LoadImage(progDir + "\flower1_32.png")
Shapes.SetOpacity(img, 20)
For x = 1 To 20
GraphicsWindow.DrawImage (img, ((Math.GetRandomNumber(24)-1)*32)+gwLeft, ((Math.GetRandomNumber(16)-1)*32)+gwTop )
EndFor
img = ImageList.LoadImage(progDir + "\flower2_32.png")
Shapes.SetOpacity(img, 20)
For x = 1 To 10
GraphicsWindow.DrawImage (img, ((Math.GetRandomNumber(24)-1)*32)+gwLeft, ((Math.GetRandomNumber(16)-1)*32)+gwTop )
EndFor


' draw the level blocks
img = ImageList.LoadImage(progDir + "\wall_32.png")
For my = 1 To 16
For mx = 1 To 24
block = text.GetSubText( level[thisLevel][my], mx, 1 )

' position WALLS
If block = "W" Then
GraphicsWindow.DrawImage (img, ((mx-1)*32)+gwLeft, ((my-1)*32)+gwTop) ' DrawRectangle( (mx-1)*32, (my-1)*32, 32, 32 )
EndIf

' position PLAYER
If block = "P" Then
player["x"] = ((mx-1)*32+12)+gwLeft ' calculate x,y from 32 x 32 level grid blocks
player["startX"] = player["x"] ' remember start position for when player dies
player["y"] = ((my-1)*32+12)+gwTop
player["startY"] = player["y"]
EndIf

' position SNAKE
If block = "S" Then
level[thisLevel]["snakeX"] = ((mx-1)*32+16)+gwLeft
level[thisLevel]["snakeY"] = ((my-1)*32+16)+gwTop
EndIf

EndFor
EndFor


' draw the border (using the snake body part)
img = ImageList.LoadImage(progDir + "\body_18.png")
For y = 0 To 600 Step 530
For x=5 to 790 Step 18
' draw top and bottom border
GraphicsWindow.DrawImage ( img, x, y)
EndFor
EndFor
For x = 0 To 800 Step 784
For y = 15 to 530 Step 18
' draw left and right border
GraphicsWindow.DrawImage ( img, x, y)
EndFor
EndFor


' show status bar
status()


' fade the screen in
Shapes.Move (bbox, 0, 0)
For lwp = 100 To 0 Step -1
Shapes.SetOpacity(bbox, lwp)
Program.Delay(20)
EndFor

EndSub


' =====================================================================


Sub snakeSetup
' create the snake array and display snake in starting position

headPart = ImageList.LoadImage(progDir + "\head_24.png")
headAngryPart = ImageList.LoadImage(progDir + "\headAngry_24.png")
headSize = 22 '24 ' radius of head
headOffset = 11

bodyPart = ImageList.LoadImage(progDir + "\body_18.png")
bodySize = 18 '18
bodyOffset = 9

tailPart = ImageList.LoadImage(progDir + "\tail_16.png")
tailSize = 16 '32 '16
tailOffset = 8

snake = ""
snake[0]["happySnake"] = Shapes.AddImage(headPart)
snake[0]["angrySnake"] = Shapes.AddImage(headAngryPart)
snakeSize = level[thisLevel]["snakeSize"] ' this value will change during game as snake eats/is eaten

' remember current pen width
'pw = GraphicsWindow.PenWidth
'GraphicsWindow.PenWidth = 0

For snakePart = 1 to snakeSize

' create the snake segments
If snakePart = 1 Then
'GraphicsWindow.BrushColor="Brown"
snake[snakePart]["sprite"] = snake[0]["happySnake"] 'Shapes.AddEllipse(headSize,headSize) ' head
' Zoom for this shape has been done above

ElseIf snakePart <> snakeSize Then
'GraphicsWindow.BrushColor="Chocolate"
snake[snakePart]["sprite"] = Shapes.AddImage(bodyPart) 'Shapes.AddEllipse(bodySize,bodySize) ' body
Else
'GraphicsWindow.BrushColor="SandyBrown"
snake[snakePart]["sprite"] = Shapes.AddImage(tailPart) 'Shapes.AddEllipse(tailSize,tailSize) ' tail
EndIf

' locate snake on screen - probably needs to be part of each level config
snake[snakePart]["x"] = level[thisLevel]["snakeX"]
snake[snakePart]["y"] = level[thisLevel]["snakeY"]

' as all segments start at the same x,y we must increment the initial delay for each successive segment
If snakePart > 2 Then
snake[snakePart]["delay"] = ((snakePart-1)*(bodySize-4))+4
Else
snake[2]["delay"] = bodySize '18
EndIf

EndFor

' set initial direction
snake[1]["moves"] = level[thisLevel]["snakeDir"]
snake[1]["delay"] = "0" ' need to initialise delay for snake head - used to determine delay before direction change

' reinstate previous pen width
'GraphicsWindow.PenWidth=pw
EndSub


' =====================================================================


Sub playerSetup
' create the player and display at start position

'GraphicsWindow.BrushColor="Lime"
img = ImageList.LoadImage(progDir + "\player2_24.png") ' from www.freeicons.dk
player["sprite"] = Shapes.AddImage(img) 'Shapes.AddRectangle( 20,20 )
Shapes.Move( player["sprite"], player["x"]-11, player["y"]-11 ) ' -11 offset instead of -12 works better!?!?!

playerMoveDelay = playerDelay ' initialise player movement speed (delay)

EndSub


' =====================================================================


Sub snakeDirection
' check if snake is ready for a CHANGE of DIRECTION

' using the 'delay' element of the snake head (snake[1]) as a counter for the change direction delay
' this delay gets decreased in the moveSnake sub
If snake[1]["delay"] = 0 Then

' reset change direction delay
snake[1]["delay"] = level[thisLevel]["dirDelay"]

' yes, time for a direction change, but only 25% chance of changing
If Math.GetRandomNumber(4) <> 3 Then

' not yet - leave the snake going the same way and delay another direction change for a while
snake[1]["delay"] = level[thisLevel]["dirDelay"]

Else
' yep, let's change direction
dir = Math.GetRandomNumber(4)

' EDGE BOUNCE - if snake is heading into window edge, force a direction change
'If (dir = 1 And snake[1]["y"] < 20) Then
' dir = 3 ' go S
'EndIf
'If (dir = 3 And snake[1]["y"] > GraphicsWindow.Height-(20)) Then
' dir = 1 ' go N
'EndIf
'If (dir = 4 And snake[1]["x"] < 20) Then
' dir = 2 ' go E
'EndIf
'If (dir = 2 And snake[1]["x"] > GraphicsWindow.Width-(8+20)) Then
' dir = 4 ' go W
'EndIf

' point snake head in appropriate direction
snake[1]["moves"] = dir

' reset delay until next direction change
snake[1]["delay"] = level[thisLevel]["dirDelay"]

EndIf



' ANGRY SNAKE calculation
' to slow this effect down, we're only trying to instigate 'angry mode' at each direction change
If (level[thisLevel]["getAngry"] = 1) Then

' only try to instigate angry mode in snake is currently happy
If angrySnake < 0 Then
'GraphicsWindow.Title="HAPPY SNAKE {:-)"

rn = Math.GetRandomNumber(100)
If (rn = 7) Then
angrySnake = Math.GetRandomNumber(50)+20
level[thisLevel]["snakeDelay"] = level[thisLevel]["snakeDelay"]/2
EndIf

' if angrySnake counter has reached zero, reset snake speed back to normal
ElseIf angrySnake = 0 Then
level[thisLevel]["snakeDelay"] = level[thisLevel]["snakeDelay"]*2 ' set snake delay back to level setting

EndIf

If angrySnake > -1 Then
angrySnake = angrySnake-1 ' decrease angry snake counter
'GraphicsWindow.Title="ANGRY SNAKE }:-/"
EndIf

EndIf

EndIf ' change direction delay=0

EndSub


' =====================================================================


Sub moveSnake
' move snake segments

For snakePart = 1 To snakeSize

' find out which direction we're moving in
dir = text.GetSubText(snake[snakePart]["moves"], 1, 1)


' check if head is about to collide with a wall
If snakePart = 1 Then
shapes.Rotate(snake[1]["sprite"], ((dir-1)*90) ) ' point snake head in correct direction

snakeCollisions()
EndIf



' only move snakepart if it's delay is zero - or this is the head, which always gets moved
If snakePart = 1 Or snake[snakePart]["delay"] = 0 Then


' take direction off moves list for this snake part
If snakePart > 1 Then
snake[snakePart]["moves"] = Text.GetSubTextToEnd(snake[snakePart]["moves"], 2)
EndIf

' add this movement onto next snake part's movement list
If snakePart < snakeSize Then
snake[snakepart+1]["moves"] = text.Append(snake[snakepart+1]["moves"],dir)
EndIf

' update x,y co-ordinates of snake part
If dir = 1 Then
snake[snakePart]["y"] = snake[snakePart]["y"]-1 ' moving N

ElseIf dir = 2 Then
snake[snakePart]["x"] = snake[snakePart]["x"]+1 ' moving E

ElseIf dir = 3 Then
snake[snakePart]["y"] = snake[snakePart]["y"]+1 ' moving S

ElseIf dir = 4 Then
snake[snakePart]["x"] = snake[snakePart]["x"]-1 ' moving W
EndIf


' wrap snake at window edge
If snake[snakePart]["x"] < gwLeft Then
snake[snakePart]["x"] = gwRight
ElseIf snake[snakePart]["x"] > gwRight Then
snake[snakePart]["x"] = gwLeft
ElseIf snake[snakePart]["y"] < gwTop Then
snake[snakePart]["y"] = gwBottom-8
ElseIf snake[snakePart]["y"] > gwBottom-8 Then
snake[snakePart]["y"] = gwTop
EndIf

EndIf


' The offsets allow for the various snake segment sizes
If snakePart = 1 Then
offset=headOffset
ElseIf snakePart<>snakeSize Then
offset = bodyOffset
Else
offset = tailOffset
EndIf

' DRAW SNAKE PART in new position
shapes.Move(snake[snakePart]["sprite"], snake[snakePart]["x"]-offset, snake[snakePart]["y"]-offset )

' DECREASE SNAKE PART DELAY
If snake[snakePart]["delay"] > 0 Then
snake[snakePart]["delay"] = snake[snakePart]["delay"] - 1
EndIf

EndFor


' as snake gets shorter, processing speed increases, so we need to add a delay
If snakeSize < 7 Then 'level[thisLevel]["snakeSize"] Then
'For snakePart = snakeSize To level[thisLevel]["snakeSize"]
Program.Delay (0.2*(level[thisLevel]["snakeSize"]-snakeSize))
'EndFor
EndIf

EndSub


' =====================================================================


Sub snakeCollisions
' this is a recursive function
' it checks for a snake collision with a level object (i.e. a wall) in the current snake direction
' if it finds one, it chooses a new direction, then calls itself to check it for a collision
' after completing, 'dir' will have a direction that does not cause a collision

' Up
If dir = 1 Then
sx = math.Floor((snake[1]["x"]-gwLeft)/32)+1
sy = math.Floor(((snake[1]["y"]-gwTop)-(headSize/2))/32)+1

If Text.GetSubText( level[thisLevel][sy], sx, 1) = "W" Then
' choose a new direction then check it for collisions by recursing this sub
dir = Math.GetRandomNumber(4)
snakeCollisions()
EndIf

' Down
ElseIf dir = 3 Then
sx = math.Floor((snake[1]["x"]-gwLeft)/32)+1
sy = math.Floor(((snake[1]["y"]-gwTop)+(headSize/2))/32)+1

If Text.GetSubText( level[thisLevel][sy], sx, 1) = "W" Then
' choose a new direction then check it for collisions by recursing this sub
dir = Math.GetRandomNumber(4)
snakeCollisions()
EndIf

' Right
ElseIf dir = 2 Then
sx = math.Floor(((snake[1]["x"]-gwLeft)+(headSize/2))/32)+1
sy = math.Floor((snake[1]["y"]-gwTop)/32)+1

If Text.GetSubText( level[thisLevel][sy], sx, 1) = "W" Then
' choose a new direction then check it for collisions by recursing this sub
dir = Math.GetRandomNumber(4)
snakeCollisions()
EndIf

' Left
ElseIf dir = 4 Then
sx = math.Floor(((snake[1]["x"]-gwLeft)-(headSize/2))/32)+1
sy = math.Floor((snake[1]["y"]-gwTop)/32)+1

If Text.GetSubText( level[thisLevel][sy], sx, 1) = "W" Then
' choose a new direction then check it for collisions by recursing this sub
dir = Math.GetRandomNumber(4)
snakeCollisions()
EndIf
EndIf

' set snake in new safe direction
snake[1]["moves"] = dir

EndSub


' =====================================================================


Sub checkKeys

' indicate if player is to move
keyPress = GraphicsWindow.LastKey

EndSub


' =====================================================================


Sub movePlayer
' depending on the key pressed, move the player in the required direction
' unless we hit the edge of the screen, or a wall

If keyPress <> "" Then ' only process if a key was pressed

move = 0 ' initially prevent any movement

' CHECK LEFT
If keyPress = "Left" Then
px = math.Floor(((player["x"]-13)-gwLeft)/32)+1 ' subtract 13 from x to allow for half sprite width offset
py = math.Floor(((player["y"]-gwTop))/32)+1

' hit edge of screen?
If player["x"]-13 > gwLeft Then
move = 1
EndIf

' hit a wall?
If Text.GetSubText( level[thisLevel][py], px, 1) = "W" Then
move = 0
EndIf
EndIf

' CHECK RIGHT
If keyPress = "Right" Then
px = math.Floor(((player["x"]+13)-gwLeft)/32)+1
py = math.Floor((player["y"]-gwTop)/32)+1

' hit edge of screen?
If player["x"]+13 < gwRight Then
move = 1
EndIf

' hit a wall?
If Text.GetSubText( level[thisLevel][py], px, 1) = "W" Then
move = 0
EndIf
EndIf

' CHECK UP
If keyPress = "Up" Then
px = math.Floor(((player["x"])-gwLeft)/32)+1
py = math.Floor(((player["y"]-13)-gwTop)/32)+1

' hit edge of screen?
If player["y"]-13 > gwTop Then
move = 1
EndIf

' hit a wall?
If Text.GetSubText( level[thisLevel][py], px, 1) = "W" Then
move = 0
EndIf
EndIf

' CHECK DOWN
If keyPress = "Down" Then
px = math.Floor(((player["x"])-gwLeft)/32)+1
py = math.Floor(((player["y"]+13)-gwTop)/32)+1

' hit edge of screen?
If player["y"]+13 < gwBottom Then
move = 1
EndIf

' hit a wall?
If Text.GetSubText( level[thisLevel][py], px, 1) = "W" Then
move = 0
EndIf
EndIf


' ADJUST PLAYER LOCATION and rotate player to point the correct direction
If keyPress = "Left" Then
player["x"] = player["x"] - move
Shapes.Rotate(player["sprite"], 270)
EndIf
If keyPress = "Right" Then
player["x"] = player["x"] + move
Shapes.Rotate(player["sprite"], 90)
EndIf
If keyPress = "Up" Then
player["y"] = player["y"] - move
Shapes.Rotate(player["sprite"], 0)
EndIf
If keyPress = "Down" Then
player["y"] = player["y"] + move
Shapes.Rotate(player["sprite"], 180)
EndIf


' MOVE PLAYER SPRITE
Shapes.Move( player["sprite"], player["x"]-11, player["y"]-11 )
keyPress = ""
EndIf
EndSub


' =====================================================================


Sub playerCollisions
' detect player colliding with various things

' detect player/snake tail collision
If (digestionDelay <= 0) Then

' have no idea why I have to subtract 4 from the tailOffset calculations here!!
If (math.Abs(player["x"] - (snake[snakeSize]["x"]-tailOffset)-4) < 10) And (Math.Abs(player["y"] - (snake[snakeSize]["y"]-tailOffset)-4) < 10) AND snake[snakeSize]["delay"] = 0 Then
digestionDelay = 60 ' don't allow another piece to be eaten for a while

' decrease snake length
snakeSize = snakeSize - 1
shapes.Remove(snake[snakeSize]["sprite"])
snake[snakeSize]["sprite"] = snake[snakeSize+1]["sprite"]

'level[thisLevel]["snakeDelay"] = level[thisLevel]["snakeDelay"] - (2*thisLevel) ' make snake faster each level - now set in level settings, therefore redundant here

Sound.PlayChimes()
score = score + 10 ' increase player score
status() ' update status area
EndIf
Else
digestionDelay = digestionDelay-1 ' just decrease the delay
EndIf

' detect player/snake head collision
If (math.Abs(player["x"] - (snake[1]["x"]-headOffset)) < 16) And (Math.Abs(player["y"] - (snake[1]["y"]-headOffset)) < 16) Then
playerEaten()
EndIf

EndSub


' =====================================================================


Sub playerEaten
' when eaten, animate the player sprite for a while

Sound.PlayBellRing()
lives = lives - 1
status() ' update status area

' set player back to their start location
player["x"] = player["startX"]
player["y"] = player["startY"]

' if player was eaten at player start location, move player to snake start location to prevent continuous death
If (math.Abs(player["x"] - (snake[1]["x"]-headOffset)) < 36) And (Math.Abs(player["y"] - (snake[1]["y"]-headOffset)) < 36) Then
player["x"] = level[thisLevel]["snakeX"]
player["y"] = level[thisLevel]["snakeY"]
EndIf

' you spin me right round baby, right round, like a record....
For x = 1 to 3
For y = 0 To 360
Shapes.Rotate( player["sprite"], y )
Shapes.SetOpacity( player["sprite"], y/2 )
Program.Delay(2)
EndFor
EndFor

If lives > 0 Then
Shapes.Animate( player["sprite"], player["x"]-11, player["y"]-11, 500 )
For lwp = 1 to 1000000
EndFor
EndIf

EndSub


' =====================================================================


Sub addSegment
' NOT USING THIS AT PRESENT - USEFUL IF FOOD IS ADDED FOR SNAKE TO EAT
' this code hasn't been updated since snake was changed from Ellipse shapes to graphic shapes, so needs some work if used!

processing = 1 ' flag that we're working on it!

' increase snake size and delay movement of new tail
snakeSize = snakeSize + 1
snake[snakeSize]["delay"] = snake[snakeSize-1]["delay"]+12

' need to remove old tail due to Small Basic's layering of graphic shapes
Shapes.Remove(snake[snakeSize-1]["sprite"])

' add a new body part
GraphicsWindow.BrushColor = "Chocolate"
snake[snakeSize-1]["sprite"] = Shapes.AddEllipse(bodySize, bodySize)
Shapes.Move(snake[snakeSize-1]["sprite"], snake[snakeSize-1]["x"], snake[snakeSize-1]["y"])

' add new tail
snake[snakeSize]["x"] = snake[snakeSize-1]["x"]
snake[snakeSize]["y"] = snake[snakeSize-1]["y"]
GraphicsWindow.BrushColor = "SandyBrown"
snake[snakeSize]["sprite"] = Shapes.AddEllipse(tailSize, tailSize)
Shapes.Move(snake[snakeSize]["sprite"], snake[snakeSize]["x"], snake[snakeSize]["y"])
EndSub

Sub mUp
' NOT USED AT PRESENT - put here to handle mouse button presses
' used in conjunction with AddSegment subroutine above
processing = 0 ' cancel the mousedown action - have to do this 'cos the 'puter is much faster than our likkle fingers
EndSub


' =====================================================================


Sub status
' show the various game values in status area

GraphicsWindow.BrushColor = "White"
GraphicsWindow.PenColor = "White"
GraphicsWindow.FontSize = 32

GraphicsWindow.DrawText ( 20, 550, "Round: Lives: Score:")
GraphicsWindow.FillRectangle ( 140,555, 80, 32 )
GraphicsWindow.FillRectangle ( 370,555, 80, 32 )
GraphicsWindow.FillRectangle ( 610,555, 160, 32 )

GraphicsWindow.BrushColor = "Black"
GraphicsWindow.DrawText ( 170, 550, thisLevel )
GraphicsWindow.DrawText ( 400, 550, lives )
GraphicsWindow.DrawText ( 640, 550, score )
EndSub


' =====================================================================


Sub levelConfig
' configuration settings for each of the levels
'
' to add new levels, simply duplicate the last one below, change it's level number, make a new layout,
' then increase the 'levels' value below. To test your new level without playing all the earlier ones, change
' the 'thisLevel' variable (at the beginning of the program code above).


levels = 5


level[1]["snakeDir"] = Math.GetRandomNumber(4) ' start snake off in a random direction: 1=N, 2=E, 3=S, 4=W
level[1]["snakeSize"] = 12 ' length of snake
level[1]["snakeDelay"]= 700 ' speed of snake (higher = slower)
level[1]["dirDelay"] = 50 ' delay (moves) before snake can change direction (lower = more jittery snake)
level[1]["getAngry"] = 1 ' flag indicating if the snake can switch to angry mode (=1) or not (=0)


' W = wall segment
' S = Snake start location
' P = Player start location

level[0][0]= ".........1.........2...." ' just a ruler
level[1][1]= "W W"
level[1][2]= " "
level[1][3]= " WWWWWWWWWWWWWW "
level[1][4]= " "
level[1][5]= " "
level[1][6]= " S "
level[1][7]= " "
level[1][8]= " "
level[1][9]= " "
level[1][10]= " "
level[1][11]= " "
level[1][12]= " P "
level[1][13]= " "
level[1][14]= " WWWWWWWWWWWWWW "
level[1][15]= " "
level[1][16]= "W W"


level[2]["snakeDir"] = Math.GetRandomNumber(4) ' start snake off in a random direction: 1=N, 2=E, 3=S, 4=W
level[2]["snakeSize"] = 14 ' length of snake
level[2]["snakeDelay"]= 1100 ' speed of snake (higher = slower)
level[2]["dirDelay"] = 50 ' delay (moves) before snake can change direction (lower = more jittery snake
level[2]["getAngry"] = 1 ' flag indicating if the snake can switch to angry mode (=1) or not (=0)

level[0][0]= ".........1.........2...." ' just a ruler
level[2][1]= " "
level[2][2]= " WWWWWWWWWWWWWWWW "
level[2][3]= " W W "
level[2][4]= " W WWWWWWWWWWWWW W "
level[2][5]= " W WW WWW WW W "
level[2][6]= " W WWWWWWWWWWWWW W "
level[2][7]= " W P WW S W "
level[2][8]= " WWWWW W WWWWWW "
level[2][9]= " WW W W "
level[2][10]= " W WWWWWWW W "
level[2][11]= " WWW W WW WW W "
level[2][12]= " W WWWW WWWWWWW W "
level[2][13]= " W W "
level[2][14]= " WWWWWWWWWWWWWWWW "
level[2][15]= " "
level[2][16]= " "


level[3]["snakeDir"] = 1 'Math.GetRandomNumber(4) ' start snake off in a random direction: 1=N, 2=E, 3=S, 4=W
level[3]["snakeSize"] = 16 ' length of snake
level[3]["snakeDelay"]= 600 ' speed of snake (higher = slower)
level[3]["dirDelay"] = 30 ' delay (moves) before snake can change direction (lower = more jittery snake
level[3]["getAngry"] = 1 ' flag indicating if the snake can switch to angry mode (=1) or not (=0)

level[0][0]= ".........1.........2...." ' just a ruler
level[3][1]= " "
level[3][2]= " WWWW WWWW "
level[3][3]= " WW W W WWW "
level[3][4]= " WW W WW "
level[3][5]= " W WWW WWW W "
level[3][6]= " W W W W "
level[3][7]= " WW WWWWW WWWWWW WW "
level[3][8]= " W P W "
level[3][9]= " WW WWWWW WWWWWW WW "
level[3][10]= " W WW W W WW W "
level[3][11]= " W WWWW WWWWW W "
level[3][12]= " WW W W WW "
level[3][13]= " WWWWWWW WWWWWWWW "
level[3][14]= " WSW "
level[3][15]= " W "
level[3][16]= " "


level[4]["snakeDir"] = 3 'Math.GetRandomNumber(4) ' start snake off in a random direction: 1=N, 2=E, 3=S, 4=W
level[4]["snakeSize"] = 18 ' length of snake
level[4]["snakeDelay"]= 500 ' speed of snake (higher = slower)
level[4]["dirDelay"] = 20 ' delay (moves) before snake can change direction (lower = more jittery snake
level[4]["getAngry"] = 0 ' flag indicating if the snake can switch to angry mode (=1) or not (=0)

level[0][0]= ".........1.........2...." ' just a ruler
level[4][1]= " W "
level[4][2]= " WSW "
level[4][3]= " W W "
level[4][4]= " W W "
level[4][5]= " W W "
level[4][6]= " W WW "
level[4][7]= " W WW "
level[4][8]= " W WW "
level[4][9]= " WW W "
level[4][10]= " WW W "
level[4][11]= " WW W "
level[4][12]= " W W "
level[4][13]= " W W "
level[4][14]= " W W "
level[4][15]= " WPW "
level[4][16]= " W "



level[5]["snakeDir"] = 3 'Math.GetRandomNumber(4) ' start snake off in a random direction: 1=N, 2=E, 3=S, 4=W
level[5]["snakeSize"] = 20 ' length of snake
level[5]["snakeDelay"]= 300 ' speed of snake (higher = slower)
level[5]["dirDelay"] = 20 ' delay (moves) before snake can change direction (lower = more jittery snake
level[5]["getAngry"] = 0 ' flag indicating if the snake can switch to angry mode (=1) or not (=0)

level[0][0]= ".........1.........2...." ' just a ruler
level[5][1]= "WW WW"
level[5][2]= "W P W"
level[5][3]= " WWWWWWWWWWWWWW "
level[5][4]= "WWWWWW WWW WW"
level[5][5]= " "
level[5][6]= " WWWWWWWWWWWWWWW "
level[5][7]= "WW WWW WWWWW"
level[5][8]= " "
level[5][9]= "WW WWW WWW WW"
level[5][10]= " WWWWWWWWWWWWWW "
level[5][11]= " "
level[5][12]= "WWWWWW WWW WW"
level[5][13]= " WWWWWWWWWWWWWW "
level[5][14]= " "
level[5][15]= "W WWWWW WWWWW W"
level[5][16]= "WW S WW"

EndSub