How do i tern this into a level?

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Dumplin Boy

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Posted: 16th Oct 2004 21:43

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How do i tern that into a level. DBC.

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EddieB

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Posted: 17th Oct 2004 04:57

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I am having the same probolem.

200GB HARD DRIVE 1GB RAM 256MB GRAPHICS CARD

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Skeletor

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Posted: 17th Oct 2004 07:35 Edited at: 17th Oct 2004 07:36

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Okay well what do you mean exactly when you say level?

If you mean how do you put that image onto the screen then its as simple as.

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load image "ImageName.bmp",1,1
paste image 1,0,0

http://www.angelfire.com/games5/db_games/

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Dumplin Boy

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Posted: 17th Oct 2004 08:21

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Yeh but how do you load your objetc to move across it (sprite).

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Skeletor

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Posted: 17th Oct 2004 09:41 Edited at: 17th Oct 2004 09:41

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http://darkbasicpro.thegamecreators.com/?m=codebase_view_code&i=1a65d2451dda6f68618bcf42dfc601be

Follow this pong code

http://www.angelfire.com/games5/db_games/

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pizzaman

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Posted: 17th Oct 2004 11:34

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Try and follow this code I made.

`****************************************************************************************
`**************************** HOW TILE BASED COLLISION WORKS ****************************
`****************************          by pizzaman           ****************************
`**************************** Date:             14/6/04      ****************************
`**************************** Time to complete: 1 hour       ****************************
`****************************************************************************************

`THE PRINCIPLE -
`the visible screen is devided up into boxes which we call tiles. This means that each
`tile is sitting on a range of coordinates. For example a 20 pixel by 20 pixel tile is
`sitting on the coordinates (0,0),(1,0).....upto (19,19). Since we know each tile is
`sitting on a range of coordinates we can check to see whether a sprite (or image) has
`the same coordinates as the tile. However, we must take into consideration that a
`sprite (or image) is usually bigger than a pixel, so we have to form a collision box
`around the sprite.

`HOW TO IMPLEMENT A TILE BASED COLLISION SYSTEM -
`Firstly we need a 2 dimensional array to store tile data in (Tile data is the image
`numbers of the of the images you are going to use; e.g. 1 could be a wall, 2 could be
`a grass image etc. Note: the image sizes should be the same as the tile size you will
`use.
`Secondly we store the data in the array. Note: you could already store data in an array
`and just load the array - this would be faster for loading times.
`Next we create some collision points around our sprite, usually 4 points which would
`be placed at the corners of the sprite creating a collision box, you could have more
`collision points if a collision box is not suitable.
`Next we have to figure out which tile in the array each collision point is on to do
`this you have to use the formula
`
`                 Tile = (x / Tile Sise, y / Tile size)
`
`                 where Tile is the tile in the array, x is the x coordinate of the
`                 collision point your checking for and y is the y coordinate of the
`                 collision point your checking for
`
`Now if the tile is a tile you dont want your sprite to go on; just reset the sprites
`coordinates to what they were before the collision and voila!!!! you've got tile
`based collision.

`****************************************************************************************
`*********************************** Start of program ***********************************
`****************************************************************************************

`gosubs are here instead of actual code, just to make things look neat
gosub screensetup
gosub createimages
gosub loaddata
gosub makeplayer

`start the main loop
do

`exit the loop if space bar is pressed - effectively ending the program
   `Note: it has to be place here and not in a gosub as it wont work
   if spacekey() = 1 then exit

gosub controls
   gosub collision

`call our home made function for displaying the tiles
   PasteTiles()

gosub displayplayer

`update screen
   sync

loop

gosub cleanup

`end the program
end

`****************************************************************************************
`************************************* End of program ***********************************
`****************************************************************************************

screensetup:

`delete anything stored in video memory
   flush video memory

`set screen resolution
   set display mode 800,600,32

`setup syncing
   sync on
   sync rate 0

return

createimages:

`create a green box
   cls rgb(0,255,0)
   get image 1,0,0,40,40,1

`create a yellow box as the player
   cls rgb(255,255,0)
   get image 2,0,0,40,40,1

`create a red box
   cls rgb(255,0,0)
   get image 10,0,0,40,40,1

`create a blue box
   cls rgb(0,0,255)
   get image 11,0,0,40,40,1

return

loaddata:

`create an array called TileMap - we will use this to store the tile data.
   `an array is like a file cabinet - in each drawer of the file cabinet there are
   `folders that hold our data. Therefore in our "file cabinet" we have 20 drawers; and
   `inside of each drawer we 15 folders; which hold data we want to access.
   `Also arrays can have up to 5 dimensions (ours has 2 dimensions) - you can visualise
   `this as being more folders inside of the other folders and so on; and of course you
   `can just have 1 dimension array as well (in other words just the drawers)
   dim TileMap(20,15)

`load data into the array - basically the computer will read 20 bits of data from one
   `data statment (at the end of the program), then move onto the next data statment
   `until all 15 data statments are read. Note: all 15 data statments could have been
   `combined into one large data statment of 300 items; the reason why its not currently
   `like that is its hard to read also you can kind of see the map the way its currently
   `written.
   for y = 0 to 14

for x = 0 to 19

read TileMap(x,y)

next x

next y

return

makeplayer:

`store predefined coordinates of player
   x1 = 380
   y1 = 280

`make the player
   sprite 1,x1,y1,2

`this sets the sprites properties; by placing a 0 in the backsave flag the background
   `behind sprite will not be saved by the computer, hence will speed up our program a
   `little. We are not using the backsave feature because we will be replacing the
   `background ourselves; this is due to when a sprite is created the 3d backdrop is
   `automatically created (a blue screen wiping any 2d images previously draw to the
   `screen) and cannot be turned off as long as you have a sprite on screen.
   set sprite 1,0,1

return

controls:

`store the x and y coordinates of the player into the variables oldx1 and oldy1
   oldx1 = x1
   oldy1 = y1

`makes the player move by altering the sprites coordinates
   if leftkey()  = 1 then x1 = x1 - 2
   if rightkey() = 1 then x1 = x1 + 2
   if upkey()    = 1 then y1 = y1 - 2
   if downkey()  = 1 then y1 = y1 + 2

return

collision:

`the following 8 lines of code stores the old and new left,right,top,bottom edges of
   `the sprite in the respective variables

`gets which tiles the current left and right co-ordinates of the player are on
   LeftTileNum   = int(x1 / 40)
   RightTileNum  = int((x1 + 39) / 40)
   `gets which tiles the current top and bottom co-ordinates of the player are on
   TopTileNum    = int(y1 / 40)
   BottomTileNum = int((y1 + 39) / 40)

`gets which tiles the old left and right co-ordinates of the player are on
   OldLeftTileNum   = int(oldx1 / 40)
   OldRightTileNum  = int((oldx1 + 39) / 40)
   `gets which tiles the old top and bottom co-ordinates of the player are on
   OldTopTileNum    = int(oldy1 / 40)
   OldBottomTileNum = int((oldy1 + 39) / 40)

`this is where we check for those 4 collision points; if the collision point is on a
   `tile you are not able to pass through (in our case a tile that has an image number
   `of 10 or greater), then the old coordinates of the sprite are restored.
   `Note: to have sliding collision we must check the the current x tile against the
   `old y tile and vice versa.

`checks for top-left collision point
   if TileMap(LeftTileNum,    OldTopTileNum)     >= 10 then x1 = oldx1
   if TileMap(OldLeftTileNum, TopTileNum)        >= 10 then y1 = oldy1

`checks for top-right collision point
   if TileMap(RightTileNum,    OldTopTileNum)    >= 10 then x1 = oldx1
   if TileMap(OldRightTileNum, TopTileNum)       >= 10 then y1 = oldy1

`checks for bottom-left collision point
   if TileMap(LeftTileNum,    OldBottomTileNum)  >= 10 then x1 = oldx1
   if TileMap(OldLeftTileNum, BottomTileNum)     >= 10 then y1 = oldy1

`checks foe bottom-right collision point
   if TileMap(RightTileNum,    OldBottomTileNum) >= 10 then x1 = oldx1
   if TileMap(OldRightTileNum, BottomTileNum)    >= 10 then y1 = oldy1

return

displayplayer:

`display sprite
   sprite 1,x1,y1,2

`show frame rate (also sometimes its useful to display debug info like player
   `player positions, program specific variables etc)
   text 10,10,str$(screen fps())

return

cleanup:

`delete any media involved in this program
   for x = 1 to 11
      if image exist(x) then delete image x
      if sprite exist(x) then delete sprite x
   next x

`delete anything thats left in the video memory - if anything
   flush video memory

return

`this is a simple user defined function - all it does is paste the tile images to the
`screen in the correct order from the array
function PasteTiles()

for y = 0 to 14

for x = 0 to 19

paste image TileMap(x,y),x*40,y*40

next x

next y

endfunction

`store tile data at the end of the program so its out of the way
data 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,1,11,1,1,1,1,1,1,1,1,11,1,11,1,1,10
data 10,1,1,11,1,1,1,1,1,1,1,1,1,1,1,1,11,1,1,10
data 10,1,1,11,1,11,1,1,1,1,1,1,1,1,11,1,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10

+ Code Snippet

`****************************************************************************************
`**************************** HOW TILE BASED COLLISION WORKS ****************************
`****************************          by pizzaman           ****************************
`**************************** Date:             14/6/04      ****************************
`**************************** Time to complete: 1 hour       ****************************
`****************************************************************************************

`THE PRINCIPLE -
`the visible screen is devided up into boxes which we call tiles. This means that each
`tile is sitting on a range of coordinates. For example a 20 pixel by 20 pixel tile is
`sitting on the coordinates (0,0),(1,0).....upto (19,19). Since we know each tile is
`sitting on a range of coordinates we can check to see whether a sprite (or image) has
`the same coordinates as the tile. However, we must take into consideration that a
`sprite (or image) is usually bigger than a pixel, so we have to form a collision box
`around the sprite.

`HOW TO IMPLEMENT A TILE BASED COLLISION SYSTEM -
`Firstly we need a 2 dimensional array to store tile data in (Tile data is the image
`numbers of the of the images you are going to use; e.g. 1 could be a wall, 2 could be
`a grass image etc. Note: the image sizes should be the same as the tile size you will
`use.
`Secondly we store the data in the array. Note: you could already store data in an array
`and just load the array - this would be faster for loading times.
`Next we create some collision points around our sprite, usually 4 points which would
`be placed at the corners of the sprite creating a collision box, you could have more
`collision points if a collision box is not suitable.
`Next we have to figure out which tile in the array each collision point is on to do
`this you have to use the formula
`
`                 Tile = (x / Tile Sise, y / Tile size)
`
`                 where Tile is the tile in the array, x is the x coordinate of the
`                 collision point your checking for and y is the y coordinate of the
`                 collision point your checking for
`
`Now if the tile is a tile you dont want your sprite to go on; just reset the sprites
`coordinates to what they were before the collision and voila!!!! you've got tile
`based collision.


`****************************************************************************************
`*********************************** Start of program ***********************************
`****************************************************************************************



`gosubs are here instead of actual code, just to make things look neat
gosub screensetup
gosub createimages
gosub loaddata
gosub makeplayer



`start the main loop
do

   `exit the loop if space bar is pressed - effectively ending the program
   `Note: it has to be place here and not in a gosub as it wont work
   if spacekey() = 1 then exit

   gosub controls
   gosub collision

   `call our home made function for displaying the tiles
   PasteTiles()

   gosub displayplayer

   `update screen
   sync

loop



gosub cleanup

`end the program
end



`****************************************************************************************
`************************************* End of program ***********************************
`****************************************************************************************



screensetup:

   `delete anything stored in video memory
   flush video memory

   `set screen resolution
   set display mode 800,600,32

   `setup syncing
   sync on
   sync rate 0

return



createimages:

   `create a green box
   cls rgb(0,255,0)
   get image 1,0,0,40,40,1

   `create a yellow box as the player
   cls rgb(255,255,0)
   get image 2,0,0,40,40,1

   `create a red box
   cls rgb(255,0,0)
   get image 10,0,0,40,40,1

   `create a blue box
   cls rgb(0,0,255)
   get image 11,0,0,40,40,1

return



loaddata:

   `create an array called TileMap - we will use this to store the tile data.
   `an array is like a file cabinet - in each drawer of the file cabinet there are
   `folders that hold our data. Therefore in our "file cabinet" we have 20 drawers; and
   `inside of each drawer we 15 folders; which hold data we want to access.
   `Also arrays can have up to 5 dimensions (ours has 2 dimensions) - you can visualise
   `this as being more folders inside of the other folders and so on; and of course you
   `can just have 1 dimension array as well (in other words just the drawers)
   dim TileMap(20,15)

   `load data into the array - basically the computer will read 20 bits of data from one
   `data statment (at the end of the program), then move onto the next data statment
   `until all 15 data statments are read. Note: all 15 data statments could have been
   `combined into one large data statment of 300 items; the reason why its not currently
   `like that is its hard to read also you can kind of see the map the way its currently
   `written.
   for y = 0 to 14

      for x = 0 to 19

         read TileMap(x,y)

      next x

   next y

return



makeplayer:

   `store predefined coordinates of player
   x1 = 380
   y1 = 280

   `make the player
   sprite 1,x1,y1,2

   `this sets the sprites properties; by placing a 0 in the backsave flag the background
   `behind sprite will not be saved by the computer, hence will speed up our program a
   `little. We are not using the backsave feature because we will be replacing the
   `background ourselves; this is due to when a sprite is created the 3d backdrop is
   `automatically created (a blue screen wiping any 2d images previously draw to the
   `screen) and cannot be turned off as long as you have a sprite on screen.
   set sprite 1,0,1

return



controls:

   `store the x and y coordinates of the player into the variables oldx1 and oldy1
   oldx1 = x1
   oldy1 = y1

   `makes the player move by altering the sprites coordinates
   if leftkey()  = 1 then x1 = x1 - 2
   if rightkey() = 1 then x1 = x1 + 2
   if upkey()    = 1 then y1 = y1 - 2
   if downkey()  = 1 then y1 = y1 + 2

return



collision:

   `the following 8 lines of code stores the old and new left,right,top,bottom edges of
   `the sprite in the respective variables

   `gets which tiles the current left and right co-ordinates of the player are on
   LeftTileNum   = int(x1 / 40)
   RightTileNum  = int((x1 + 39) / 40)
   `gets which tiles the current top and bottom co-ordinates of the player are on
   TopTileNum    = int(y1 / 40)
   BottomTileNum = int((y1 + 39) / 40)

   `gets which tiles the old left and right co-ordinates of the player are on
   OldLeftTileNum   = int(oldx1 / 40)
   OldRightTileNum  = int((oldx1 + 39) / 40)
   `gets which tiles the old top and bottom co-ordinates of the player are on
   OldTopTileNum    = int(oldy1 / 40)
   OldBottomTileNum = int((oldy1 + 39) / 40)


   `this is where we check for those 4 collision points; if the collision point is on a
   `tile you are not able to pass through (in our case a tile that has an image number
   `of 10 or greater), then the old coordinates of the sprite are restored.
   `Note: to have sliding collision we must check the the current x tile against the
   `old y tile and vice versa.

   `checks for top-left collision point
   if TileMap(LeftTileNum,    OldTopTileNum)     >= 10 then x1 = oldx1
   if TileMap(OldLeftTileNum, TopTileNum)        >= 10 then y1 = oldy1

   `checks for top-right collision point
   if TileMap(RightTileNum,    OldTopTileNum)    >= 10 then x1 = oldx1
   if TileMap(OldRightTileNum, TopTileNum)       >= 10 then y1 = oldy1

   `checks for bottom-left collision point
   if TileMap(LeftTileNum,    OldBottomTileNum)  >= 10 then x1 = oldx1
   if TileMap(OldLeftTileNum, BottomTileNum)     >= 10 then y1 = oldy1

   `checks foe bottom-right collision point
   if TileMap(RightTileNum,    OldBottomTileNum) >= 10 then x1 = oldx1
   if TileMap(OldRightTileNum, BottomTileNum)    >= 10 then y1 = oldy1

return



displayplayer:

   `display sprite
   sprite 1,x1,y1,2

   `show frame rate (also sometimes its useful to display debug info like player
   `player positions, program specific variables etc)
   text 10,10,str$(screen fps())

return



cleanup:

   `delete any media involved in this program
   for x = 1 to 11
      if image exist(x) then delete image x
      if sprite exist(x) then delete sprite x
   next x

   `delete anything thats left in the video memory - if anything
   flush video memory

return



`this is a simple user defined function - all it does is paste the tile images to the
`screen in the correct order from the array
function PasteTiles()

   for y = 0 to 14

      for x = 0 to 19

         paste image TileMap(x,y),x*40,y*40

      next x

   next y

endfunction




`store tile data at the end of the program so its out of the way
data 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,1,11,1,1,1,1,1,1,1,1,11,1,11,1,1,10
data 10,1,1,11,1,1,1,1,1,1,1,1,1,1,1,1,11,1,1,10
data 10,1,1,11,1,11,1,1,1,1,1,1,1,1,11,1,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,11,11,1,1,1,1,1,1,1,1,1,1,11,11,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,10
data 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10

Remember that the tiles can resemble a floor, sky, walls, etc

pizzaman

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Skeletor

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Posted: 17th Oct 2004 13:13

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@ pizzaman

Thats totally awesome!

That code not only helps newbs but it can also help more experienced 2d coders. Last night I kept thinking of how I would implement tile collision but your code has shown me the way. Keep up the good work

http://www.angelfire.com/games5/db_games/

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EddieB

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Posted: 17th Oct 2004 18:49

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Thanks.

200GB HARD DRIVE 1GB RAM 256MB GRAPHICS CARD

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pizzaman

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Posted: 18th Oct 2004 08:23

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Thanks for the compliments

. Tile collision is the way to go for most 2D games and is relatively easy once you get your head round it. Anyways if you need more help just ask, I usually patrol the 2D forums every 3-4 days - I wish I had more time.

pizzaman

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Dumplin Boy

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Posted: 26th Oct 2004 05:34

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Ok, Thanks.

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Sly D

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Posted: 29th Oct 2004 20:42

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Hey pizzaman your code helped me very much! I just have one question. How do you make that map scroll???

A cute looking koala with a WHAT!? THEY can't use Kalashnikovs, can they?

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pizzaman

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Posted: 30th Oct 2004 02:23 Edited at: 30th Oct 2004 02:29

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hi Cyber Freak

I'm making a late entry to the competition, so unfortunately I can't show you how to scroll those tiles yet - maybe next week when I have some time.

Edit Note: This is for scrolling a map so the player is always at the centre of the screen ala Zelda/Mario.

The concept is pretty easy though, you have an extra row and column of tiles offscreen. Once the player moves, you've got to move all the tiles in the opposite direction by the the same speed (including the offscreen tiles). Then when the offscreen tiles become fully visible you place some more offscreen tiles to keep up the illusion of a scrolling world.

You should check out the code base and look for Ian M's scrolling tile map.

pizzaman

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Blue Shadow

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Posted: 30th Oct 2004 03:10

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Hey i just wondered what happens if your tiles dont fill an exact square such as a ramp. If you want the player to travel up and down a ramp then you cant use whole tiles. Theres a picture of my level that im trying to work out collision attached to this post (click the download button at the bottom right)

Hope you can help, Cheers,

Mike (Code Monkey)

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pizzaman

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Posted: 30th Oct 2004 03:40 Edited at: 30th Oct 2004 08:48

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@ Code Monkey

One way to do that is to create a set of collision rules for each tile. So if the tile your on is a ramp,the player will follow ramp collision.

Ramp Collision -
First you find out how far the player is in the ramp tile (and the direction of the tile). Based on how far the player is in the tile, raise or lower (depending on the ramp's and player's direction), the players coordinates. You also need to consider how steep the ramp is.

For example if you had a ramp tile(thats 50 by 50 pixels) that was lower at the left side, at a 45 degree angle and the player was heading right (assuming that their also 50 by 50 pixels); if the player was half in the ramp tile (at the left side) you would raise them by 12.5 pixels, if they were fully in the ramp tile they would be raised to 25 pixels; and if they were half in the ramp tile (at the right side) they would be raised to 37.5 pixels.

Hope that helps
pizzaman

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Blue Shadow

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Joined: 6th Feb 2004

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Posted: 2nd Nov 2004 01:31

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Thanks for your help pizzaman. I might try and implement tile collision into my platform game then.

Cheers,

Code Monkey (Mike)

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pizzaman

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Years of Service

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Joined: 18th Feb 2004

Location: Gateshead, UK

Posted: 8th Nov 2004 03:05 Edited at: 13th Nov 2004 04:38

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Well its been a week, so heres the code to scroll a tile map

`****************************************************************************************
`**************************** HOW TILE BASED COLLISION WORKS ****************************
`****************************          by pizzaman           ****************************
`**************************** Date:             14/6/04      ****************************
`**************************** Time to complete: 1 hour       ****************************
`****************************************************************************************

`THE PRINCIPLE -
`The visible screen is devided up into boxes which we call tiles. This means that each
`tile is sitting on a range of coordinates. For example a 20 pixel by 20 pixel tile that
`is the top-left most tile is sitting on the coordinates (0,0) to (19,19). Since we know
`each tile is sitting on a range of coordinates we can check to see whether a sprite (or
`image) has the same coordinates as the tile. However, we must take into consideration
`that a sprite (or image) is usually bigger than a pixel, so we have to form a collision
`box around the sprite.

`HOW TO IMPLEMENT A TILE BASED COLLISION SYSTEM -
`Firstly we need a 2 dimensional array to store tile data in (Tile data is the image
`numbers of the of the images you are going to use; e.g. 1 could be a wall, 2 could be
`a grass image etc. Note: the image sizes should be the same as the tile size you will
`use.
`Secondly we store the data in the array. Note: you could already store data in an array
`and just load the array - this would be faster for loading times.
`Next we create some collision points around our sprite, usually 4 points which would
`be placed at the corners of the sprite creating a collision box, you could have more
`collision points if a collision box is not suitable.
`Next we have to figure out which tile in the array each collision point is on to do
`this you have to use the formula
`
`                 Tile = (x / Tile Sise, y / Tile size)
`
`                 where Tile is the tile in the array, x is the x coordinate of the
`                 collision point your checking for and y is the y coordinate of the
`                 collision point your checking for
`
`Now if the tile is a tile you dont want your sprite to go on; just reset the sprites
`coordinates to what they were before the collision and voila!!!! you've got tile
`based collision.

`rem out along with the ending one to execute this program
remstart

`gosubs are here instead of actual code, just to make things look neat
gosub screensetup
gosub createimages
gosub loaddata
gosub makeplayer

`start the main loop
do

`exit the loop if space bar is pressed - effectively ending the program
   `Note: it has to be place here and not in a gosub as it wont work
   if spacekey() = 1 then exit

gosub controls
   gosub collision

`call our home made function for displaying the tiles
   PasteTiles()

gosub displayplayer

`update screen
   sync

loop

gosub cleanup

`end the program
end

`****************************************************************************************
`************************************* End of program ***********************************
`****************************************************************************************

screensetup:

`delete anything stored in video memory
   flush video memory

`set screen resolution
   set display mode 800,600,32

`setup syncing
   sync on
   sync rate 150