Tiles + Collision need help

[Rewrite]

Hey short time reader, first time poster to these forums. I've recently picked up on turing and am currently compiling a game of my own. But being a newbie I've run into some problems that I was hoping some of the pros of this forum could help me out with.
Like many NES games before I was hoping to create my game using the tile system. So far I've been successful in creating a program that takes in a txt file and converts it into tiles, and than a character that moves around on that screen and scales the map. Although my problem lies in the fact that I cannot figure out how collision would work, so if someone could provide some insite onto the subject I would greatly appreciate it

Here is what I have worked on as of now. (heres to hoping the code html works)

code:

setscreen ("graphics:500;400,offscreenonly") View.Set ("noecho") var playerx : int := maxx div 2 var playery : int := maxy div 2 var changex : int := 0 var changey : int := 0 var maptownstartx : int := 0 var maptownstarty : int := 0 var tilenumber : int := 30 var stream : int var size : int := 36 open : stream, "003.map", get var pictures : array 1 .. size, 1 .. size of int var pic1 : int := Pic.FileNew ("001.bmp") var pic2 : int := Pic.FileNew ("002.bmp") var pic3 : int := Pic.FileNew ("003.bmp") var pic4 : int := Pic.FileNew ("004.bmp") var pic5 : int := Pic.FileNew ("005.bmp") var pic6 : int := Pic.FileNew ("006.bmp") var pic7 : int := Pic.FileNew ("007.bmp") var pic8 : int := Pic.FileNew ("008.bmp") var pic9 : int := Pic.FileNew ("009.bmp") var pic10 : int := Pic.FileNew ("010.bmp") var playerdown1 : int := Pic.FileNew ("walkdown1.bmp") var playerdown2 : int := Pic.FileNew ("walkdown2.bmp") var playerup1 : int := Pic.FileNew ("walkup1.bmp") var playerup2 : int := Pic.FileNew ("walkup2.bmp") var playerright1 : int := Pic.FileNew ("walkright1.bmp") var playerright2 : int := Pic.FileNew ("walkright2.bmp") var playerleft1 : int := Pic.FileNew ("walkleft1.bmp") var playerleft2 : int := Pic.FileNew ("walkleft2.bmp") for i : 1 .. size     get : stream, skip     exit when eof (stream)     for j : 1 .. size         get : stream, pictures (i, j)     end for end for close : stream procedure maptown for i : 1 .. size     for j : 1 .. size         if pictures (i, j) = 001 then             Pic.Draw (pic1, Pic.Width (pic1) * (j - 1 + changex), maxx - Pic.Height (pic1) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 002 then             Pic.Draw (pic2, Pic.Width (pic2) * (j - 1 + changex), maxx - Pic.Height (pic2) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 003 then             Pic.Draw (pic3, Pic.Width (pic3) * (j - 1 + changex), maxx - Pic.Height (pic3) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 004 then             Pic.Draw (pic4, Pic.Width (pic4) * (j - 1 + changex), maxx - Pic.Height (pic4) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 005 then             Pic.Draw (pic5, Pic.Width (pic5) * (j - 1 + changex), maxx - Pic.Height (pic5) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 006 then             Pic.Draw (pic6, Pic.Width (pic6) * (j - 1 + changex), maxx - Pic.Height (pic6) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 007 then             Pic.Draw (pic7, Pic.Width (pic7) * (j - 1 + changex), maxx - Pic.Height (pic7) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 008 then             Pic.Draw (pic8, Pic.Width (pic8) * (j - 1 + changex), maxx - Pic.Height (pic8) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 009 then             Pic.Draw (pic9, Pic.Width (pic9) * (j - 1 + changex), maxx - Pic.Height (pic9) * (i + 3 + changey), picCopy)         elsif pictures (i, j) = 010 then             Pic.Draw (pic10, Pic.Width (pic10) * (j - 1 + changex), maxx - Pic.Height (pic10) * (i + 3 + changey), picCopy)                 end if     end for end for end maptown procedure walk (down1, down2, funx, funy : int)     Draw.Cls     Time.Delay (150)     maptown     Pic.Draw (down2, funx, funy, picMerge)     View.Update     Draw.Cls     Time.Delay (150)     maptown %     Pic.Draw (down1, funx, funy, picMerge)     View.Update end walk procedure playgame     var chars : array char of boolean     loop         Input.KeyDown (chars)         if chars (KEY_UP_ARROW) then  changey += 1  walk (playerup1, playerup2, playerx, playery)     elsif chars (KEY_RIGHT_ARROW) then changex -= 1 walk (playerright1, playerright2, playerx, playery)         elsif chars (KEY_LEFT_ARROW) then             changex += 1             walk (playerleft1, playerleft2, playerx, playery)         elsif chars (KEY_DOWN_ARROW) then             changey -= 1             walk (playerdown1, playerdown2, playerx, playery)         end if      end loop end playgame playgame

[Tony]

it is quite simple.

you just have to validate move procedures. Let me explain:

first you move your character vertually. Such as calcualte the new position your character will move to and save that to a temp variable. You then check the tile type that is in that location. If it's something you don't want your character to walk on (water, wall, etc), your validation returns false and you don't move the character.

[Rewrite]

Thanks, I can understand the whole theory behind tiles and why it works. But what I'm having trouble with is Pic.Draw files colliding with other Pic.Draw files. I've seen plently of tutorials on Draw.Boxs or whatever colliding with each other, but not Pic.Draws and bmps hitting each other, and I don't know about this 'whatdotcolor' system, but I doubt it would work properly for multicolor tiles (if stone steps and stonewalls of a bmp are the same grey how does turing know how to collid with the stonegrey wall and not the stonegrey ground?)

[TheXploder]

Whatdot colour will not work for sure. Now the concept with tiles is to make a 2d array and for each 0 in the 2d array place a grass tile lets say and for a 1 a wall. So the spacing of the tiles doesn't matter, what matters is where the object is located on the map.

2 is the players location..

1111
1201
1001
1001
1111

so then to make a check...

code:

if key (right) and map (playerx + 1, playery) = 0 then       //move right end if