void UIListView::setColumnVisible( int col, bool show )
{
if ( columnVisible( col ) == show )
return ;
ColumnData * data = m_data.find( col );
if ( show == false )
{
data->name = columnText( col );
data->size = columnWidth( col );
data->mode = columnWidthMode( col );
setColumnText ( col, "" );
setColumnWidth( col, 0 );
setColumnWidthMode( col, QListView::Manual );
header()->setResizeEnabled( false, col );
}
else
{
setColumnText ( col, data->name );
setColumnWidth( col, data->size );
setColumnWidthMode( col, data->mode );
header()->setResizeEnabled( true, col );
}
}
int visible(DataSet *terrain, GridPoint start, GridPoint end, float fNODATA)
{
GridPoint p;
float x0, y0, x1, y1, y_start;
float dx, dy, dydx;
int idx;
float h0, h1;
double dzds;
assert(start.r >= 0 && start.c >= 0);
assert(end.r >= 0 && end.c >= 0);
assert(start.r < terrain->grid.nrow && start.c < terrain->grid.ncol);
assert(end.r < terrain->grid.nrow && end.c < terrain->grid.ncol);
if (gpEqual(start, end)) {
gpSlope(terrain, start, end, h0, h1, dzds);
if (h0 == fNODATA || h1 == fNODATA)
return 0;
else
return 1;
}
// calculate slope in x and y
gpCenter(start, x0, y0);
gpCenter(end, x1, y1);
gpDiff(start, end, dx, dy);
if (dx == 0) {
idx = 0;
dydx = 0; // not used
}else {
// idx is +1 or -1
idx = (int)(dx / fabs(dx));
dydx = dy / dx;
}
// calculate the z gradient
gpSlope(terrain, start, end, h0, h1, dzds);
if (h0 == fNODATA || h1 == fNODATA)
return 0;
y_start = y1 = y0;
x1 = x0;
p = start;
// run through columns
while (p.c >= 0 && p.c < terrain->grid.ncol &&
p.r >= 0 && p.r < terrain->grid.nrow) {
// increment x1 by a column, or half a column
if (p.c == start.c || p.c == end.c)
x1 += .5 * idx;
else
x1 += idx;
// calculate next y intercept
y0 = y1;
if (idx == 0)
y1 = y0 + dy;
else
y1 = y_start + dydx * (x1 - x0);
// translate y intercept to row index
p.r = dy >= 0 ? (int)y0 : (int)(ceilf(y0) - 1);
// check column visibility
if (gpBefore(p, end, dx, dy) &&
!columnVisible(terrain, start, p, dzds, y0, y1, fNODATA))
return 0;
// proceed to next column
p.c += idx;
}
return 1;
}
