re. Using Vectors Issue could anyone help ?

[DGEN]

Hi all
I am a bit of a learner in C++ what i need to know is how to read a vector without having to put a number in square braces.

I am making a program using an engine called Irrlicht to develop the application (RPG Builder 3D) and I use the mouse pointer to select a node (model) and repaint it but i only want it to paint the nodes[] vector and not anything else

IMeshSceneNode<Vector>* Nodes;

For (i=1024*4*3 ; i<1024 ; i++)
{
nodes.PushBack(i); //etc etc
}

for example (this is not the official code but it is simular)

so there are over 900 nodes in total nodes[900] - how do i get the program to look for the nodes[] Vector without me having to specify a node for it to check

if ( SelectedSceneNode == nodes[#] && SelectedSceneNode != Models[#]){ a += 1;} for example

if it is possible can you help me please.

Cheers

 

[ArkM]

1. Use CODE tag to present your snippets (see Process TGML link on the form). Please, don't present unofficial code like this above: it's not the C++ and it's not some reasonable pseudocode.
2. Is it std::vector using issue? If so:

vector<NodeClass> nodes;
...
for (...)
{
   nodes.push_back(Node class object reference/* not an index!*/);
}

and so on. Why to read a vector without having to put a number in square braces?

Try to reformulate your true problem, please.
I'm afraid nobody can help you in that woolly style context.

 

[DGEN]

Hi again

Ok I appologise for being so vague earlier below is the official code for the sections that i stated

 if (selectedSceneNode != 0 && selectedSceneNode != nodes[900])
{
selectedSceneNode->setMaterialTexture( 0, driver->getTexture(TilePic[T]) );
}

where i have selectedSceneNode != nodes[900] this is the code that i would like help on i do not want to have to put a number in here something like selectedSceneNode == nodes[#]

is there a possibility of doing something with this

also is it something to do with the below code that features earlier in the solution

IAnimatedMesh* mesh = smgr->getMesh("Objects/floor.dmf");
vector<IAnimatedMeshSceneNode*> nodes; 

// Creating five of them: 
for (int Boxes = -Ammountofblocks*Ammountofblocks*1024*3; Boxes < 1024*Ammountofblocks*Ammountofblocks; Boxes+=1024) 
{ 
   nodes.push_back(smgr->addAnimatedMeshSceneNode(mesh)); 
} 

// Initialise the created nodes 

for (size_t i = 0; i < nodes.size(); ++i) 

{ 
 if (AblocksLine >= Ammountofblocks*1024) {Ablocksdown +=  1024;AblocksLine =-Ammountofblocks*1024;}
      nodes[i]->setMaterialFlag(EMF_LIGHTING, false); 
      nodes[i]->setMaterialTexture( 0, driver->getTexture(TilePic[T]));

      nodes[i]->setPosition(vector3df(AblocksLine,0,Ablocksdown)); 
  nodes[i]->setMaterialFlag(EMF_FOG_ENABLE,true);
AblocksLine +=1024;
//nodes[i]->setDebugDataVisible(true);
Tempy[i]=Ablocksdown ;
Tempx[i]=AblocksLine-1024;

//ISceneNode* selectedSceneNode = smgr->getSceneCollisionManager()->getSceneNodeFromScreenCoordinatesBB(getPosition()); 

}

 

[cpjust]

I'm still not sure exactly what you're asking, but if you don't want to specify a number in the braces, you can use an iterator. Ex:

vector<int> nums;

for ( int i = 0; i < 10; ++i )
{
   nums.push_back(i);
}

for ( vector<int>::iterator it = nums.begin(); it != nums.end(); ++it )
{
   cout << *it << endl;
}

 

[DGEN]

Hi again

Ok what you are saying is for me to use an iterator when i first place the nodes into my scene is this correct?

will this then allow me to not need to enter a number into the if statement later where the array is mentioned?

so i would be able to use the vector and get the software to know that i am looking at the array as a group and not just a single node. could it be possible to elaborate on this a bit as i dont really understand what it is this code will do, though i will try it anyway.

Thank you for your help

Cheers

 

[cpjust]

Use push_back() to add new elements to the end of the vector. Then you can use an iterator to read through all the elements of the vector and/or change existing element values.
If you want to treat the vector as one big array, you can do this:

void SomeFunction( node*  pNodes )
{
   // Do whatever you want with pNodes.
}

int main()
{
   vector<node> nodes;
   ...
   SomeFunction( nodes[0] );  // Pass the whole array to the function.
   ...
}

 

[cpjust]

Oops, I forgot to take the address of nodes[0] when passing to the function:

SomeFunction( &nodes[0] );