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Paul C Skertich

How do I create multiple instances of class?

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Say for instance, inside my C++ .NET Editor, I want to import a mesh and another mesh and another mesh. What I notice is for instance, "Cube1" and "Cube2" both using same shader and same set to a position. When I run the editor only one will show. Does it have to do with the final matrixs? For instance the:

[code]
cBuffer.final = worldMatrix * viewMatrix * projectionMatrix;

[/code]

Could it be because both basic colored cubes are using the same World Matrix? Do they have to be different World Matrixes?

I looked into creating the model class in a default indexer class, just not really sure if this would be a good idea.

All I need to know is what to do when regarding multiple instances of the same class so, I can set the position and rotation, shaders or what not independantly.

Thanks for all the help and time.

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[i]worldMatrix [/i]defines where object is, if you use same matrix for both cubes you just end up drawing two cubes at the same place, therefore you cannot see second one. So yes, you need different world matrix.

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For some odd reason my brain is having more Brain Farts than usual. It's been like this all day today. I created a property index and configured worldMatrix to have multiple ones. I'm not sure if I was clear but when I go in my editor and for instance import a mesh - I want ti create a incremental index. I also want the class to know okay, since this is a new index then we'll use this.

If I say,

[code]

Cube1 ^ = Model = gcnew(Model);
Cube2 ^ = Model = gcnew(Model);

[/code]

I want the Cube1 to have it's own index and the Cube2 have it's own index, so therefore it can difficuate when using worldMatrix. So, Cube1 generates index 0 and cube2 generates a index 1. Both seperate indexes. I wonder if it's because when I created a Model(const Model ^) { } it copied or something. I don't know much of CLI C++ still learning more about it.

Thanks for the reply!

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I could but for some reason inside the editor when I would create a new class - it would automatically assume to position one cube. The managed dll it like this:

[code]
namespace ModelManager {

public ref class Model {
private:

public:

Model() {

}

// This use to be in there.

Model(const Model^) {

}

};

}
[/code]

I'm not sure if the Model(const Model^) is a copy constructor or what. I'm fairly understanding C++ .NET. So, what I was talking about is inside the Editor when I would say in the Form1 public constructor.

[code]
Cube1 = gcnew(Model);
Cube2 = gcnew(Model);

[/code]

it wouldn't realize that there's a difference. But your idea Sami was what I was heading for. Wait, my gears are turning and I think we're syncing. Okay, so you mean the WorldMatrix created inside the model class, right? As of now I have the worldMatrix to be global outside of the whole entire managed environment. Is this what you mean?

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[quote name='SIC Games' timestamp='1344190868' post='4966413']
I could but for some reason inside the editor when I would create a new class - it would automatically assume to position one cube. The managed dll it like this:

[code]
...
[/code]

it wouldn't realize that there's a difference. But your idea Sami was what I was heading for. Wait, my gears are turning and I think we're syncing. Okay, so you mean the WorldMatrix created inside the model class, right? As of now I have the worldMatrix to be global outside of the whole entire managed environment. Is this what you mean?
[/quote]

I mean that you should have the world matrix as a member in your Model class, together with appropriate getters and setters and manipulation methods. Methods could be such ones that translates, rotates, scales... Edited by SamiHuutoniemi

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Since it's a managed DLL for the editor's engine - it reports with a error saying Mixed types are not supported in Managed. So, that's why I declared them above the managed namespaces. However, your idea Sami what I had in mind.

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Are you saying you cannot do something similar to this?
[CODE]
public class ModelData {
public void draw() {
device->SetIndexBuffer(...);
...
device->Draw(...);
}
};
public class ModelInstance {
Matrix transform;
ModelData ^model;
public void setTransform();
public Matrix getTransform();
public void draw() {
device->SetWorldMatrix(transform);
model->draw();
}
};
[/CODE] Edited by Ripiz

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You cannot have a native class as value member in a managed class, but you are allowed to have pointers to native classes.
So if "Matrix" is your native class you cannot do:

ref class Model
{
public:
Matrix matrix;
};

but you can do:

ref class Model
{
public:
Matrix* matrix;
};

In your constructor, you have to construct the native matrix with new Matrix().

Having said that, I think you have a bigger problem here as your architecture is totally wrong. A "Model" class should be living the native side of the code, because it is not strictly an "editor" thing... your editor will create and edit models that will then be used by the native engine in the game. In this case what you do? You'll have to implement one model for the native side and one model for the managed side? That is really asking for troubles.

You should have a Model class in native and then, you create a EditorModel managed class that just wraps the native class with properties and member functions.

[CODE]ref class EditorModel
{
public:
EditorModel()
{
model=new Model();
}

float getWhatever()
{
return model->getWhatever();
}
private:
Model* model;
};[/CODE] Edited by kunos

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[quote name='SIC Games' timestamp='1344193112' post='4966430']
Ripiz, I'm only targeting DX 11 instead of 9. So, yes I can't do it. Since SetWorldMatrix is part of DirectX 9 when I looked it up on google.
[/quote]
Well it was just an abstract example. Store ID3D11Buffer instead of Matrix, and update it when you set new transform (or update it before rendering). Edited by Ripiz

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