1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
//---------------------------------------------------------------------------//
// Copyright (c) 2013-2014 Kyle Lutz <kyle.r.lutz@gmail.com>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//
#ifndef BOOST_COMPUTE_INTEROP_VTK_BOUNDS_HPP
#define BOOST_COMPUTE_INTEROP_VTK_BOUNDS_HPP
#include <vector>
#include <iterator>
#include <boost/compute/system.hpp>
#include <boost/compute/command_queue.hpp>
#include <boost/compute/algorithm/copy_n.hpp>
#include <boost/compute/algorithm/reduce.hpp>
#include <boost/compute/container/array.hpp>
namespace boost {
namespace compute {
/// Calculates the bounds for the points in the range [\p first, \p last) and
/// stores the result in \p bounds.
///
/// For example, this can be used to implement the GetBounds() method for a
/// vtkMapper subclass.
template<class PointIterator>
inline void vtk_compute_bounds(PointIterator first,
PointIterator last,
double bounds[6],
command_queue &queue = system::default_queue())
{
typedef typename std::iterator_traits<PointIterator>::value_type T;
const context &context = queue.get_context();
// compute min and max point
array<T, 2> extrema(context);
reduce(first, last, extrema.begin() + 0, min<T>(), queue);
reduce(first, last, extrema.begin() + 1, max<T>(), queue);
// copy results to host buffer
std::vector<T> buffer(2);
copy_n(extrema.begin(), 2, buffer.begin(), queue);
// copy to vtk-style bounds
bounds[0] = buffer[0][0]; bounds[1] = buffer[1][0];
bounds[2] = buffer[0][1]; bounds[3] = buffer[1][1];
bounds[4] = buffer[0][2]; bounds[5] = buffer[1][2];
}
} // end compute namespace
} // end boost namespace
#endif // BOOST_COMPUTE_INTEROP_VTK_BOUNDS_HPP
|
