More Trouble - Loop Not Iterating Properly

agonvs

Hi all,

My program is stuck and I've managed to figure out where the hitch is. The collide function, which is supposed to iterate through a list of tiles and return the type, is apparently not iterating properly as it prints out the same set of coordinates over and over. Could somebody look this over and see if anything jumps out?

Here's player.h:

#SelectExpand
  1//#include "entity.h"
  2#include <allegro5\allegro.h>
  3#include <list>
  4#include "globals.h"
  5#include "tile.h"
  6
  7enum facing {RIGHT, LEFT};
  8
  9class Player
 10{
 11private:
 12  std::list<Tile*> mTiles;
 13  std::list<Tile*>::iterator mIter;
 14  int mX, mY, mVelX, mVelY, bottomFrame, topFrame, fallIndex, idleCount, idleIndex;
 15  bool tint, flip, justFell;
 16  int mJumpInts[30];
 17  int mFallInts[30];
 18  facing mFacing;
 19  direction mDir;
 20  ALLEGRO_BITMAP* mImage;
 21  ALLEGRO_COLOR color;
 22public:
 23  int getVelX(){return mVelX;}
 24  int getVelY(){return mVelY;}
 25  int collide(int footX, int footY);
 26  void west();
 27  void none();
 28  void east();
 29  void idle();
 30  void walk();
 31  void jump();
 32  void fall();
 33  void shoot();
 34  void Initialize(int x, int y,  ALLEGRO_BITMAP* image, std::list<Tile*> Tiles, std::list<Tile*>::iterator iter);
 35  void Update(direction dir, ALLEGRO_JOYSTICK_STATE jst);
 36  void Render();
 37  bool collide(int x, int y, int width, int height);
 38};

And here's player.cpp:

#SelectExpand
   1#include<iostream>
   2#include<list>
   3#include"player.h"
   4#include"globals.h"
   5#include"tile.h"
   6using namespace std;
   7
   8void Player::Initialize(int x, int y, ALLEGRO_BITMAP* image, std::list<Tile*> Tiles, std::list<Tile*>::iterator iter)
   9{
mX = x;
mY = y;
mVelX = 0;
mVelY = 0;
bottomFrame = 1;
topFrame = 0;
tint = false;
flip = false;
mFacing = RIGHT;
mDir = EAST;
mImage = image;
mTiles = Tiles;
mIter = iter;
idleCount = 0;
idleIndex = 1;
mJumpInts[0] = -16;
mJumpInts[1] = -16;
mJumpInts[2] = -16;
mJumpInts[3] = -16;
mJumpInts[4] = -8;
mJumpInts[5] = -8;
mJumpInts[6] = -8;
mJumpInts[7] = -8;
mJumpInts[8] = -4;
mJumpInts[9] = -4;
mJumpInts[10] = -4;
mJumpInts[11] = -4;
mJumpInts[12] = -2;
mJumpInts[13] = -2;
mJumpInts[14] = -2;
mJumpInts[15] = -2;
mJumpInts[16] = -1;
mJumpInts[17] = -1;
mJumpInts[18] = -1;
mJumpInts[19] = -1;
mJumpInts[20] = -1;
mJumpInts[21] = -1;
mJumpInts[22] = -1;
mJumpInts[23] = -1;
mJumpInts[24] = 0;
mJumpInts[25] = 0;
mJumpInts[26] = 0;
mJumpInts[27] = 0;
mJumpInts[28] = 0;
mJumpInts[29] = 0;
mFallInts[0] = 0;
mFallInts[1] = 0;
mFallInts[2] = 0;
mFallInts[3] = 0;
mFallInts[4] = 0;
mFallInts[5] = 0;
mFallInts[6] = 1;
mFallInts[7] = 1;
mFallInts[8] = 1;
mFallInts[9] = 1;
mFallInts[10] = 1;
mFallInts[11] = 1;
mFallInts[12] = 1;
mFallInts[13] = 1;
mFallInts[14] = 2;
mFallInts[15] = 2;
mFallInts[16] = 2;
mFallInts[17] = 2;
mFallInts[18] = 4;
mFallInts[19] = 4;
mFallInts[20] = 4;
mFallInts[21] = 4;
mFallInts[22] = 8;
mFallInts[23] = 8;
mFallInts[24] = 8;
mFallInts[25] = 8;
mFallInts[26] = 16;
mFallInts[27] = 16;
mFallInts[28] = 16;
mFallInts[29] = 16;
  85}
  86
  87void Player::Update(direction dir, ALLEGRO_JOYSTICK_STATE jst)
  88{
if (dir == EAST)
  east();
if (dir == NONE)
  none();
if (dir == WEST)
  west();
if (justFell && !(jst.button[0]))
  justFell = false;
if (!(justFell) && jst.button[0])
  jump();
  99}
 100
 101void Player::Render()
 102{
if (mFacing == RIGHT)
{
  al_draw_bitmap_region(mImage, (bottomFrame*128), 0, 128, 128, mX, mY, 0);
  al_draw_bitmap_region(mImage, (topFrame*128), 0, 128, 128, mX, mY, 0);
}
else
{
  al_draw_bitmap_region(mImage, (bottomFrame*128), 0, 128, 128, mX, mY, ALLEGRO_FLIP_HORIZONTAL);
  al_draw_bitmap_region(mImage, (topFrame*128), 0, 128, 128, mX, mY, ALLEGRO_FLIP_HORIZONTAL);
}
 113}
 114
 115void Player::east()
 116{
mFacing = RIGHT;
int tile = collide(102, 122);
if (tile == 1)
{
  walk();
  fallIndex = 0;
}
else if (tile == 2)
  mVelX = 0;
else
  fall();
 128}
 129
 130void Player::west()
 131{
mFacing = LEFT;
int tile = collide(32, 122);
if (tile == 1)
{
  walk();
  fallIndex = 0;
}
else if (tile == 2)
  mVelX = 0;
else
  fall();
 143}
 144
 145void Player::none()
 146{
//cout << "In function none()" << endl;
mVelX = 0;
if (mFacing == RIGHT)
{
  int tile = collide(102,122);
  //cout << "Tile: " << tile << endl;
  if (tile == 1)
    idle();
  else
    fall();
}
else
{
  int tile = collide(32,122);
  //cout << "Tile: " << tile << endl;
  if (tile == 1)
    idle();
  else
    fall();
}
 167}
 168
 169
 170void Player::idle()
 171{
if (idleCount == 5)
{  
  idleCount = 0;
  if (idleIndex == 4)
    idleIndex = 1;
  else
    idleIndex++;
}
idleCount++;
bottomFrame = 0;
topFrame = idleIndex;
cout << "In function idle()" << endl;
 184}
 185
 186int Player::collide(int footX, int footY)
 187{
//cout << "mX: " << mX << " mY: " << mY << " footX: " << footX << " footY: " << footY << endl;
for (mIter = mTiles.begin(); mIter != mTiles.end(); ++mIter)
{
  if ((*mIter)->isDrawable())
  {
    cout << (*mIter)->getX() << " " << (*mIter)->getY() << endl;
    if ((mX + footX >= (*mIter)->getX()) && (mY + footY >= (*mIter)->getY()) && (mX + footX < (*mIter)->getX() + 128) && (mY + footY < (*mIter)->getY()+128))
    {  
      if ((*mIter)->getType() == 1)
      {
        if (mY + footY > (*mIter)->getY() + 64)
        {
          mY = 58;
          mVelY = 0;
          justFell = true;
          (*mIter)->setTint(true);
          return 1;
        }
        (*mIter)->setTint(true);
        return 0;
      }
      else if ((*mIter)->getType() == 2)
      {
        (*mIter)->setTint(true);
        return 2;
      }
    }
    else
    {
      (*mIter)->setTint(false);
      return 0;
    }

  }
 222
}
 224}
 225
 226void Player::walk()
 227{
 228
 229}
 230
 231void Player::jump()
 232{
 233
 234}
 235
 236void Player::fall()
 237{
 238
 239}

I know the list itself initialized properly because the tiles display correctly on the screen. It's just that in this other Player class, things seem to get hung up in the Collide function. And yes, there is more than just one drawable tile, otherwise there would be no screen.

EDIT: I figured out what I was doing wrong. By using return statements I was exiting the loop before it had finished.

Chris Katko

Quote:

std::list<Tile*> mTiles;
//...
if ((*mIter)->isDrawable())

FYI, you're already using a list, so you don't need to use Tile pointers, you could just use Tiles. There are situations where you need pointers (polymorphism--storing a derived class in a list of base class type), but this probably isn't it.

This works just as fine:

std::list<Tile> mTiles;
//...
 if ((mIter)->isDrawable())

As for the return values you've found, don't forget that you can use "break" and "continue" to control loop flow.

Thread #615281. Printed from Allegro.cc