106     xvol->tex->ctr.y = 0.0;  in newextvol()
196     if (ry->d.y == 0.0) {  in ext_volume_texture()
197         if ((ry->o.y < bx->min.y) || (ry->o.y > bx->max.y))  in ext_volume_texture()
201         ty1 = (bx->min.y - ry->o.y) / ry->d.y;  in ext_volume_texture()
202         ty2 = (bx->max.y - ry->o.y) / ry->d.y;  in ext_volume_texture()
248     bln.y = fabs(bx->min.y - bx->max.y);  in ext_volume_texture()
258             pnt.y = ((ry->o.y + (ry->d.y * t)) - bx->min.y) / bln.y;  in ext_volume_texture()
262             scalar = xvol->evaluator(pnt.x, pnt.y, pnt.z);  in ext_volume_texture()
278                 N.x = (xvol->evaluator(pnt.x - ddt, pnt.y, pnt.z) -  in ext_volume_texture()
279                        xvol->evaluator(pnt.x + ddt, pnt.y, pnt.z)) *  in ext_volume_texture()
282                 N.y = (xvol->evaluator(pnt.x, pnt.y - ddt, pnt.z) -  in ext_volume_texture()
283                        xvol->evaluator(pnt.x, pnt.y + ddt, pnt.z)) *  in ext_volume_texture()
286                 N.z = (xvol->evaluator(pnt.x, pnt.y, pnt.z - ddt) -  in ext_volume_texture()
287                        xvol->evaluator(pnt.x, pnt.y, pnt.z + ddt)) *  in ext_volume_texture()
291                 if ((N.x * N.x + N.y * N.y + N.z * N.z) > 0.0) {  in ext_volume_texture()