item scale

yvanvds · 09-12-2010 08:42 PM

Hey, i know i can scale a Game::Item with the scale member variable. But how to scale just one dimension instead of all 3 at the same time?

Regards,

yvan

Zervox · 09-12-2010 09:06 PM

youmesh.scale(Vec(0,0,0));

**Esenthel** · 09-13-2010 05:00 PM

it's better to scale drawing matrix instead of the mesh
physical actors don't support non-uniform scales

yvanvds · 09-13-2010 09:29 PM

Well i did try to scale the mesh, like Zervox suggested. Works great on its own but then every item with the same mesh is also changed. And it seems there is no copy constructor for a mesh, so i guess i'm not meant to copy them when i create an object?

For matrixes, i came up with this code, but obviously i'm doing something wrong since it only makes the object disappear.

Code:

// setup new scaling

Vec scale;

scale.x = 1.0 + (lastWidth - tmp);

scale.y = 1.0;

scale.z = 1.0 + (lastWidth - tmp);

// get the item matrix and scale it

Matrix m;

item->matrix();

m.setScale(scale);

// add matrix to the item again

item->matrix(m);

Guess i have to look at the Matrix tutorials again?

Dynad · 09-13-2010 09:56 PM

Well you need to set its matrix before drawing.

SetMatrix(MatrixIdentity);

yvanvds · 09-19-2010 11:52 AM

Well i don't get it. I must be using matrix the wrong way, but i've read the tutorials over and over again, and can't see how i should do this.

I've moved the scale function to the item's drawSolid routine. And made sure it's called. If I use the SetMatrix(m) function, all my objects are on the same spot. I don't see why since i'm only changing the scaling.

And if i use this->matrix(m), nothing happens.

If anyone would like to see the code:

Code:

UInt Item::drawPrepare() {

    UInt modes = __super::drawPrepare() | IndexToFlag(RM_OVERLAY) | IndexToFlag(RM_SOLID);

    return modes;

}

void Item::drawSolid() {

     // newScale is set from another function

    Vec tempScale;

    tempScale.x = 1.0 + (oldScale - newScale);

    tempScale.y = 1.0;

    tempScale.z = 1.0 + (oldScale - newScale);

    oldScale = newScale;

    Matrix m;

    m = this->matrix();

    m.setScale(tempScale);

    SetMatrix(m);

    //this->matrix(m);

    __super::drawSolid();

}

Driklyn · 09-19-2010 09:12 PM

Any method that starts with "set" resets the matrix when called. Try using "m.scale(tempScale);" instead.

item scale
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