Car racing game --- mapping system help

[lil_mickey]

Hi, im currently working on my final project, which is an overhead view car racing game. I have a few questions about the mapping system...

I'm going to have it like in most RPg's, where the character ( or in this case, the car), stays in the middle of the screen, while the map moves. I'm having a few problems implementing this. How would you do this, so that you dont draws the whole track( which is going to be huge) at one time, but draws it screen by screen ,without hard-coding??? Im sorry if this is confusing, it if is, tell ne, and ill try to explain it what i mean.

Heres what i have so far....its doesn't work too well.

code:

% What is this? My attempt at our (Dejan and I) mapping system...it stinks, but it's a start! % setting the screen setscreen ("graphics:640;480,nobuttonbar,nocursor,position:top;center,offscreenonly") % yes these variables are global...get over it!! % half of these variables im not even using yet % static variables (variables that will change depending on what track is chosen) var TrackWidth : int := 10 % number of screens wide a track is var TrackHeight : int := 5 % number of screens high a track is var screenHieght : int := 480 % hieght of one screen var screenWidth : int := 640 % width of one screen var screenDirectory : string := "screens1/" var NumberofScreens : int := 10 % number of screen files for that particular track % other variables var TrackData : int % text File with the data for that particular track var ScreenImages : array 1 .. NumberofScreens of int var MapX : int := 1 % x co-ordinate of map var MapY : int := 1 % y co-ordinate of map var chars : array char of boolean % for input.KeyDown var MoveSpeed : int := 5 % amount of pixels map will move each time var car := Pic.FileNew ("bmw-325.bmp") Pic.SetTransparentColor (car, 13) car := Pic.Scale (car, Pic.Width (car) div 1.5, Pic.Height (car) div 1.5) var mainMap : int var count := 1 %%%%%%%%%procedures%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % procedure readData % read data about specific track procedure LoadScreens % for loading maps     put "Loading Maps..."     for i : 1 .. NumberofScreens         ScreenImages (i) := Pic.FileNew (screenDirectory + intstr (i) + ".bmp") %Load every image, in order, from the file folder that holds the screens     end for end LoadScreens procedure DrawCar % drawing the car     Pic.Draw (car, 320 - (Pic.Width (car) div 2), 240 - (Pic.Height (car) div 2), picMerge) % Draws car at center end DrawCar procedure DrawMap % long and inefficient mapping system...currently under construction!     cls     if MapX > Pic.Width (mainMap) or MapY > Pic.Height (mainMap) then         mainMap := ScreenImages (count)     end if     if MapX > 1 then % drawing new maps...needs fixing!!!         if ScreenImages (count) = mainMap then % basically, when main map moves right, it draws another map to the left of it             count -= 1         end if         Pic.Draw (ScreenImages (count), MapX - Pic.Width (mainMap), MapY, picCopy)     end if     if MapX < 1 then % when main map moves right, draws another map to the right of main map         if ScreenImages (count) = mainMap then             count += 1         end if         Pic.Draw (ScreenImages (count), MapX + Pic.Width (mainMap), MapY, picCopy)     end if     if MapY > 1 then % when main map moves up, draws another map underneath         if ScreenImages (count) = mainMap then             count += 1         end if         Pic.Draw (ScreenImages (count), MapX, MapY - Pic.Height (mainMap), picCopy)     end if     if MapY < 1 then % when the main map moves down, dras another one above it         if ScreenImages (count) = mainMap then             count -= 1         end if         Pic.Draw (ScreenImages (count), MapX, MapY + Pic.Height (mainMap), picCopy)     end if     Pic.Draw (mainMap, MapX, MapY, picCopy)     if MapX > 1 and MapY > 1 then % when map moves up AND left, draws a map at lower left corner         if ScreenImages (count) = mainMap then             count += 1         end if         Pic.Draw (ScreenImages (count), MapX - Pic.Width (mainMap), MapY - Pic.Height (mainMap), picCopy)     end if     if MapX < 1 and MapY < 1 then      % when map moves down and right, draws map at upper right corner         if ScreenImages (count) = mainMap then             count -= 1         end if         Pic.Draw (ScreenImages (count), MapX + Pic.Width (mainMap), MapY + Pic.Height (mainMap), picCopy)     end if if MapX < 1 and MapY > 1 then % when map moves up and right, draws map at lower right corner     if ScreenImages(count) = mainMap then         count += 1         end if         Pic.Draw (ScreenImages (count), MapX + Pic.Width (mainMap), MapY - Pic.Height(mainMap), picCopy)         end if                 if MapX > 1 and MapY < 1 then  % when map moves down and left, draws a map at upper left corner     if ScreenImages(count) = mainMap then         count -= 1         end if         Pic.Draw (ScreenImages (count), MapX - Pic.Width (mainMap), MapY + Pic.Height(mainMap), picCopy)         end if end DrawMap procedure Move % moving the map!     if chars (KEY_UP_ARROW) then % depending on what you press, the co-ordinates of the map will change         MapY -= MoveSpeed     end if     if chars (KEY_DOWN_ARROW) then         MapY += MoveSpeed     end if     if chars (KEY_LEFT_ARROW) then         MapX += MoveSpeed     end if     if chars (KEY_RIGHT_ARROW) then         MapX -= MoveSpeed     end if     % self explanitory end Move %%%%%%%%%% main program %%%%%%%%%%%% LoadScreens mainMap := ScreenImages (5) loop     View.Update     DrawMap % loads map     DrawCar % draws car in middle, over the map     Input.KeyDown (chars)     Move % determines new co-ordinates for the next loop end loop

i keep getting errors with my arrays..any help would be appreciated!

[jamonathin]

Well, next time throw everything into a zip file, because we cant run it properly without the images.

I'm guessing that its one simple image of a track, that you're going to draw twice. What you can do is assign two x, y and pic variables to the images.

Turing:

var x, y, pic: array 1 .. 2 of int pic (1) := Pic.FileNew ("map.jpg") pic (2) := pic (1) x (1) := 0 x (2) := 0 y (1) := 0 y (2) := Pic.Height ( pic (1) ) %Starts at the very tip of the picture.

Now what you can do is just make a procedure that checks if the map needs to be moved back to where it started.

Turing:

procedure move_back      for i : 1 .. 2 %Checking if that picture is too low to be shown          if y (i) + Pic.Height (pic (1)) <= 0 then               y (i) := Pic.Height (pic (1))          end if %Moving it back up to the tip of the other picture       end for end move_back

You can use the same concept if the player is moving backwards. Just use y(i) >=maxx and y (i) := -Pic.Height.

[lil_mickey]

hey sorry, ill put it in a zip file next time...i wasnèt really thinkin when i posted this Thats not exactly what i was trying to do, but what you explained did give me a couple of ideas on how i could cut down on some lines of code if i did have to draw the same picture over and over again.

Right now, the way i have it,i have to make every screen a different picture( even if some of the screens, especially on straight-aways, are exactly the same). That seems like it will take up alot of space and im trying to find a better, more effecient way , so that making multiple maps wont be such a chore. I was thinking that it could read info from a text file and map it like that (similar to many tile engines ),but im pretty unfamiliar with working with text files in turing.

But anyways thanks for the help, ill keep what you said in mind. I posted it in a zip file so you can see how it works. Any other suggestions will be greatly appreciated