Some questions

[thetaf]

Hi ! Another irrlicht user here with some questions waiting for answers!

Question 1 :
I have the following code for my hero's movement :

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void move(ISceneNode* node,const vector3df<f32>& add)
{
        node->setPosition(node->getPosition() + add);
}
 
if(keys[up])
        move(hero,vector3df(0,0,10.0f * elapsed);
 
if(keys[down])
        move(hero,vector3df(0,0,-(10.0f * elapsed));
 
 

But there is a big problem with it : my hero doesn't follow a straight path relative to its current rotation
Can anyone tell me what's wrong with it?

Question 2 :
Which is the best way to fire a projectile at a specified target so that it will produce smooth movement ?

Thanks for any help!

[serengeor]

But there is a big problem with it : my hero doesn't follow a straight path relative to its current rotation
Can anyone tell me what's wrong with it?

Why would he?
You didn't make him follow it and he didn't bother to do so on its own

Question 2 :
Which is the best way to fire a projectile at a specified target so that it will produce smooth movement ?

Get a start point, end point. Subtract end point from start point and normalize the new vector. You'll have a direction in which your projectile should go. Then you just multiply that direction vector by velocity and delta time.
Or you can use irrlicht's 'fly straight' animator.

[blAaarg]

Answer 1:

Look into rotationToDirection() and use its return vector scaled before sending it as the second parameter to move().
I don't recall if you'll need to normalize it first.

Answer 2:

Subtract the shooter's position from the target's position. (Otherwise, you'll shoot backwards). Then call move() on the projectile the same way you did to the hero. What the projectile does when it hits or misses is up to you.

[thetaf]

Thanks both of you.

Look into rotationToDirection() and use its return vector scaled before sending it as the second parameter to move().
I don't recall if you'll need to normalize it first.

Oh my god , thank you , that's exactly what i wanted and works as expected !!!


As for question 2 :

Get a start point, end point. Subtract end point from start point and normalize the new vector. You'll have a direction in which your projectile should go. Then you just multiply that direction vector by velocity and delta time.
Or you can use irrlicht's 'fly straight' animator.

Subtract the shooter's position from the target's position. (Otherwise, you'll shoot backwards). Then call move() on the projectile the same way you did to the hero. What the projectile does when it hits or misses is up to you.

So if i get it right , its just :

When adding the projectile to my array :

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vector3df<f32> source = hero->getPosition();
vector3df<f32> destination = source - target->getPosition();
destination = destination.normalize();
 

 
Then in update code of the projectile array:

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source += (destination * velocity) * elapsed;
 

?

[blAaarg]

No, sorry. What I meant by "subtract...from" was:

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vector3df<f32> destination = target->getPosition() - source;  // the shooter is the 'source'

not

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vector3df<f32> destination = source - target->getPosition();

Although, I would not have chosen the name 'source' to represent the position of a moving projectile , as long as your update code has access to 'source', I do believe that should work.

Hopefully, I understood that correctly and that helps.

[thetaf]

Thanks for making it clear.

My hero can't use his gear yet , so i haven't tested the above code.... but i will do so after im done
with the controls!

[thetaf]

By the way , im facing another issue.
I can't get the directx drivers to work but the opengl.I think its because of codeblock's compiler , because i can use fine all drivers with ms vc .

Any idea how to fix this

[Brainsaw]

The default codeblocks project does only include the OpenGL driver. There is a tutorial on the wiki (http://irrlicht3d.org/wiki/index.php?n= ... 9WithMinGW) on how to compile Irrlicht with DirectX using MinGW.

[thetaf]

Thank you!
It took me some time but got it to work

[thetaf]

I have another problem.Im making a zelda tile game clone to 3d ;but when im generating the world i get this :


The tile texture is this :


And the code is this :

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void generateDungeon(int sx,int sy,int sz,int tileSize)
{
        vector3df scale = vector3df(tileSize,tileSize,tileSize);
 
        /*
                [][][][][][][]
                [][][][][][][]
                [][][][][][][]
                [][][][][][][]
                [][][][][][][]
        */
 
        for(int i = 0;i<sy;i++)
        {
                int h = i * tileSize;
 
                for(int j = 0;j<sx;j++)
                {
                        int w = j * tileSize;
 
                        for(int k = 0;k<sz;k++)
                        {
                                ISceneNode* tile = smgr->addCubeSceneNode();
                                setTexture(tile,"test.bmp");
                                setLighting(tile,false);
                                setScale(tile,scale);
                                setPosition(tile,vector3df(k * tileSize,height , w));
                        }
                }
        }
}
 

What am i doing wrong the dungeon is rendered like this

[serengeor]

You didn't read carefully how cube is created

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virtual IMeshSceneNode *        addCubeSceneNode (f32 size=10.0f, ISceneNode *parent=0, s32 id=-1, const core::vector3df &position=core::vector3df(0, 0, 0), const core::vector3df &rotation=core::vector3df(0, 0, 0), const core::vector3df &scale=core::vector3df(1.0f, 1.0f, 1.0f))=0
///Adds a cube scene node.

When you skipped the first default parameter it created a cube of size 10, then you scaled it 10 times so the cube size is now 100.

[thetaf]

You didn't read carefully how cube is created

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virtual IMeshSceneNode *        addCubeSceneNode (f32 size=10.0f, ISceneNode *parent=0, s32 id=-1, const core::vector3df &position=core::vector3df(0, 0, 0), const core::vector3df &rotation=core::vector3df(0, 0, 0), const core::vector3df &scale=core::vector3df(1.0f, 1.0f, 1.0f))=0
///Adds a cube scene node.

When you skipped the first default parameter it created a cube of size 10, then you scaled it 10 times so the cube size is now 100.

It worked by passing 1.0f to the addCubeSceneNode function