According to the topic Pushing local objects into a list
The full class:
class Invader
{
public:
Invader(const Invader&other);
Invader();
~Invader();
public:
void Init(InvaderTypes invadertype, CIw2DImage *AlienImage);
void Update(float dt);
void Render();
void SetAlienImage(CIw2DImage *image){ mImageAlien = image; }
void setVisible(bool show) { Visible = show; }
bool isVisible() const { return Visible; }
Iw2DSceneGraph::CSprite *AlienSprite;
Iw2DSceneGraph::CAtlas *AlienAtals;
CIw2DImage *mImageAlien;
std::list<Bullet*> *Bullets;
CIwFMat2D Transform; // Transform matrix
bool Visible; // Sprites visible state
bool Canfire;
};
Invader::Invader()
{
}
Invader::Invader(const Invader&other)
{ // Create EnemyTop atlas
AlienAtals = new CAtlas();
AlienSprite = new CSprite();
*AlienAtals = *other.AlienAtals;
*AlienSprite = *other.AlienSprite;
}
Invader::~Invader()
{
for (std::list<Bullet*>::iterator it = Bullets->begin(); it != Bullets->end(); ++it)
delete *it;
delete Bullets;
delete AlienAtals;
delete AlienSprite;
}
void Invader::Init(InvaderTypes invadertype, CIw2DImage *AlienImage)
{
if (invadertype == InvaderTypes::TOP_ALIEN)
{
//SetAlienImage(AlienImage);
mImageAlien = AlienImage;
// Create EnemyTop atlas
int frame_w = (int)(mImageAlien->GetWidth() / 2);
int frame_h = (int)(mImageAlien->GetHeight());
AlienAtals = new CAtlas(frame_w, frame_h, 2, mImageAlien);
AlienSprite = new CSprite();
AlienSprite->m_X = 0;
AlienSprite->m_Y = 0;
AlienSprite->SetAtlas(AlienAtals);
AlienSprite->m_W = (float)AlienAtals->GetFrameWidth();
AlienSprite->m_H = (float)AlienAtals->GetFrameHeight();
AlienSprite->m_AnchorX = 0.5;
AlienSprite->SetAnimDuration(2);
}
else if (invadertype == InvaderTypes::MIDDLE_ALIEN)
{
}
else if (invadertype == InvaderTypes::LAST_ALIEN)
{
}
Visible = true;
Bullets = new std::list<Bullet*>();
Canfire = true;
}
I added the objects by doing:
list<Invader> invaders;
int spacing = 10;
for (int i = 0; i < 5; i++)
{
Invader invader;
invader.Init(TOP_ALIEN, gameResources->getAlienImageTop());
invader.AlienSprite->m_X = 50 + spacing;
invaders.push_back(invader);
spacing += 50;
}
the usage: Right now it causes an access violation when accessing (it)
for (list<Invader>::iterator it = invaders.begin(); it != invaders.end(); it++)
{
(it)->Update(FRAME_TIME);
(it)->Render();
}
You can see the result here in the following image:
First, during Invader::Init())
, you provide a copy of the pointer to AlienImage
. Then when you copy the object into the std::list
, you don't copy that same pointer to the new object. Further, during Invader::Invader(const Invader& other)
, you are not making a copy of Invader::Bullets
. This leaves both the values uninitialized causing Undefined Behavior upon access (which probably occurs in (it)->Update(FRAME_TYIME);
and/or (it)->Render();
-- I can't verify since you didn't provide a MCVE .
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