how create RayCasting?

how create RayCasting?
i have seen some videos, but without success :(
so i ask: and someone told me that use 1 pixel, or the square size it's the same.. so i did these function:

Code:

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void DrawRays(){
    //getting the player map position:
    int MapX = floor(PlayerPosX / 32);
    int MapY = floor(PlayerPosY / 32)
   
    //getting the player position for the destination line:
    double DestinationX = PlayerPosX;
    double DestinationY = PlayerPosY;
   
    //testing if i'm on previous hit wall:
    while (LevelMap0[MapY-1][MapX-1] != 1)
    {
        //if don't hit the wall,
        //add the 1 for Map position combined with palyer radians:
        MapX += cos(PlayerRadians);
        MapY += sin(PlayerRadians);
       
        //then we add the square size, by player radians, on destination line:
        DestinationX += cos(PlayerRadians)*32;
        DestinationY += sin(PlayerRadians)*32;




    }
    DrawLine(PlayerPosX, PlayerPosY, DestinationX, DestinationY, RGB(0, 255, 0));
}

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problems:
- if i change the player radians, the program seems freeze :(
- if i move, i can get the same line size :(

Hi, can you post a picture showing an example of this working (or not working). I don't quite understand what's happening. Also is LevelMap0[x][y] just a two dimensional array? This might be easier with a picture or a bit more explanation, thanks :)