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Graphics / SFML collision detection

« on: November 22, 2014, 05:06:58 am »

I am trying to develop maps like the ones in this game (1)

Well, my current algorithm could be hacky but I have a problem detecting  collisions.

I have the following code but apparently, I still have collisions like (2). I am not sure what is wrong with the code but it is surely not giving the expected results.

/*
 * Set the number of leafs dictated by the level, very simple implementation
 * that does not come up with as cute a maps Set the first leaf at the middle
 * of the map, for an even 'i' generate a random  x-coordinate while for an odd
 * 'i' generate a y-coordinate, check for overlap/collision, hack the coordinates
 * further if one exists
 */
leafenvironment::leafenvironment(int level) {
  srand(time(nullptr));
  for (size_t i = 0; i < level; i++) {
    lily *current = new lily();
    leafs.push_back(current);
  }
  // first lily at centre of window and redundant stuff
  for (size_t i = 0; i < level; i++) {
    if (i == 0) {
      pos *current = new pos;
      current->x = WIDTH / 2;
      current->y = HEIGHT / 2;
      position.push_back(current);
      assert(leafs[i]);
      leafs[i]->SetPosition(position[i]->x, position[i]->y);
      leafs[i]->GetSprite().setScale(0.5f, 0.5f);
      continue;
    }
 
    float newpos = static_cast<float>(rand() % 10);
    if (i % 2) {
      pos *current = new pos;
      current->x = newpos * 30;
      current->y = position[i - 1]->y;
      position.push_back(current);
      assert(leafs[i]);
      leafs[i]->SetPosition(position[i]->x, position[i]->y);
      leafs[i]->GetSprite().setScale(0.5f, 0.5f);
      for (size_t j = i - 1; j <= 0; j--) {
        while (leafs[i]->GetSprite().getGlobalBounds().intersects(leafs[j]->GetSprite().getGlobalBounds())) {
          leafs[i]->SetPosition(position[i]->x * 100, position[i]->y);
        }
      }
    } else {
      pos *current = new pos;
      current->x = position[i - 1]->x;
      current->y = newpos * 30;
      position.push_back(current);
      assert(leafs[i]);
      leafs[i]->SetPosition(position[i]->x, position[i]->y);
      leafs[i]->GetSprite().setScale(0.5f, 0.5f);
      for (size_t j = i - 1; j <= 0; j--) {
        while (leafs[i]->GetSprite().getGlobalBounds().intersects(leafs[j]->GetSprite().getGlobalBounds())) {
          leafs[i]->SetPosition(position[i]->x, position[i]->y * 100);
        }
      }
    }
  }
}
 

I think of developing an algorithm where I  use an a 2-d array to represent the window grid some thing like

#include <cstdlib>
#include <ctime>
#include <iostream>
#include <vector>

char grid[15][16] = {
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0},
    {' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',0}
};

int main()
{
    srand (time(NULL));

    int x = rand() % 15, y = rand() % 15;

    grid[x][y] = '@';

    for (int lily = 0; lily < 10; ++lily)
    {
        std::vector<std::pair<int,int>> avail;
        for (int ix = x+1; ix < 15; ++ix)
        {
            if (grid[ix][y] == '@')
            {
                break;
            }
            avail.push_back(std::make_pair(ix,y));
        }
        for (int ix = x-1; ix >= 0; --ix)
        {
            if (grid[ix][y] == '@')
            {
                break;
            }
            avail.push_back(std::make_pair(ix,y));
        }

        for (int iy = y+1; iy < 15; ++iy)
        {
            if (grid[x][iy] == '@')
            {
                break;
            }
            avail.push_back(std::make_pair(x,iy));
        }
        for (int iy = y-1; iy >= 0; --iy)
        {
            if (grid[x][iy] == '@')
            {
                break;
            }
            avail.push_back(std::make_pair(x,iy));
        }
        std::pair<int,int> xy = avail[rand() % avail.size()];
        x = xy.first;
        y = xy.second;
        grid[x][y] = '@';
    }

    for (int i = 0; i < 15; ++i)
    {
        std::cout << grid[i] << std::endl;
    }
}

but then I am stuck at how to map the filled array onto the window grid. Could someone please point me in the right direction?

1)http://www.psdevwiki.com/ps3/Scogger_HD
2)http://imgur.com/a/pBEyh