/*
* rcrv
*
* draws a rational curve
*
*/
void
rcrv(Coord (*geom)[4])
{
Matrix d, tmp;
float *m, xlast, ylast, zlast;
Token *tok;
int i;
if (!vdevice.initialised)
verror("rcrv: vogl not initialised");
mult4x4(d, vdevice.tbasis, geom);
/*
* Find the last point on the curve....
*/
xlast = d[0][0] + d[1][0] + d[2][0] + d[3][0];
ylast = d[0][1] + d[1][1] + d[2][1] + d[3][1];
zlast = d[0][2] + d[1][2] + d[2][2] + d[3][2];
/*
* Mult. by the precision matrix....
*/
mult4x4(tmp, e, d);
if (vdevice.inobject) {
tok = newtokens(21);
tok[0].i = RCURVE;
(++tok)->i = nsegs;
(++tok)->f = xlast;
(++tok)->f = ylast;
(++tok)->f = zlast;
m = (float *)tmp;
for (i = 0; i < 16; i++)
(++tok)->f = *m++;
return;
}
/*
* Multiply by the current transformation matrix.
*/
mult4x4(d, tmp, vdevice.transmat->m);
/*
* Draw the curve.....
*/
drcurve(nsegs, d);
/*
* Set the current world position to the last point (This
* is the untransformed one)
*/
vdevice.cpW[V_X] = xlast;
vdevice.cpW[V_Y] = ylast;
vdevice.cpW[V_Z] = zlast;
}
/*
* multmatrix
*
* Premultipy the top matrix on the stack by "mat"
*
*/
void
multmatrix(float (*mat)[4])
{
Matrix prod;
float *m;
Token *p;
int i;
if (vdevice.inobject) {
p = newtokens(17);
p[0].i = MULTMATRIX;
m = (float *)mat;
for (i = 0; i < 16; i++)
(++p)->f = *m++;
return;
}
mult4x4(prod, mat, vdevice.transmat->m);
loadmatrix(prod);
}
void FrustumPlanes::CalculateFrustumPlanes() {
// normalize value
float n = 0.0;
// Calculate a combined MVP from MV and P
mult4x4(_mvp, _p, _mv);
// Extract the frustum's left clipping plane and normalize it.
_planes[0][0] = _mvp[3] + _mvp[0];
_planes[0][1] = _mvp[7] + _mvp[4];
_planes[0][2] = _mvp[11] + _mvp[8];
_planes[0][3] = _mvp[15] + _mvp[12];
n = (float) sqrt(_planes[0][0] * _planes[0][0] +
_planes[0][1] * _planes[0][1] +
_planes[0][2] * _planes[0][2]);
_planes[0][0] /= n;
_planes[0][1] /= n;
_planes[0][2] /= n;
_planes[0][3] /= n;
// Extract the frustum's right clipping plane and normalize it.
_planes[1][0] = _mvp[3] - _mvp[0];
_planes[1][1] = _mvp[7] - _mvp[4];
_planes[1][2] = _mvp[11] - _mvp[8];
_planes[1][3] = _mvp[15] - _mvp[12];
n = (float) sqrt(_planes[1][0] * _planes[1][0] +
_planes[1][1] * _planes[1][1] +
_planes[1][2] * _planes[1][2]);
_planes[1][0] /= n;
_planes[1][1] /= n;
_planes[1][2] /= n;
_planes[1][3] /= n;
// Extract the frustum's bottom clipping plane and normalize it.
_planes[2][0] = _mvp[3] + _mvp[1];
_planes[2][1] = _mvp[7] + _mvp[5];
_planes[2][2] = _mvp[11] + _mvp[9];
_planes[2][3] = _mvp[15] + _mvp[13];
n = (float) sqrt(_planes[2][0] * _planes[2][0] +
_planes[2][1] * _planes[2][1] +
_planes[2][2] * _planes[2][2]);
_planes[2][0] /= n;
_planes[2][1] /= n;
_planes[2][2] /= n;
_planes[2][3] /= n;
// Extract the frustum's top clipping plane and normalize it.
_planes[3][0] = _mvp[3] - _mvp[1];
_planes[3][1] = _mvp[7] - _mvp[5];
_planes[3][2] = _mvp[11] - _mvp[9];
_planes[3][3] = _mvp[15] - _mvp[13];
n = (float) sqrt(_planes[3][0] * _planes[3][0] +
_planes[3][1] * _planes[3][1] +
_planes[3][2] * _planes[3][2]);
_planes[3][0] /= n;
_planes[3][1] /= n;
_planes[3][2] /= n;
_planes[3][3] /= n;
// Extract the frustum's far clipping plane and normalize it.
_planes[4][0] = _mvp[3] - _mvp[2];
_planes[4][1] = _mvp[7] - _mvp[6];
_planes[4][2] = _mvp[11] - _mvp[10];
_planes[4][3] = _mvp[15] - _mvp[14];
n = (float) sqrt(_planes[4][0] * _planes[4][0] +
_planes[4][1] * _planes[4][1] +
_planes[4][2] * _planes[4][2]);
_planes[4][0] /= n;
_planes[4][1] /= n;
_planes[4][2] /= n;
_planes[4][3] /= n;
// Extract the frustum's near clipping plane and normalize it.
_planes[5][0] = _mvp[3] + _mvp[2];
_planes[5][1] = _mvp[7] + _mvp[6];
_planes[5][2] = _mvp[11] + _mvp[10];
_planes[5][3] = _mvp[15] + _mvp[14];
n = (float) sqrt(_planes[5][0] * _planes[5][0] +
_planes[5][1] * _planes[5][1] +
_planes[5][2] * _planes[5][2] );
_planes[5][0] /= n;
_planes[5][1] /= n;
_planes[5][2] /= n;
_planes[5][3] /= n;
}
