blender-archive/source/blender/blenlib/BLI_utildefines_iter.h

/* SPDX-License-Identifier: GPL-2.0-or-later */

#pragma once

/** \file
 * \ingroup bli
 *
 * General looping helpers, use `BLI_FOREACH` prefix.
 */

/**
 * Even value distribution.
 *
 * \a src must be larger than \a dst,
 * \a dst defines the number of iterations, their values are evenly spaced.
 *
 * The following pairs represent (src, dst) arguments and the values they loop over.
 * <pre>
 * (19, 4) ->    [2, 7, 11. 16]
 * (100, 5) ->   [9, 29, 49, 69, 89]
 * (100, 3) ->   [16, 49, 83]
 * (100, 100) -> [0..99]
 * </pre>
 * \note this is mainly useful for numbers that might not divide evenly into eachother.
 */
#define BLI_FOREACH_SPARSE_RANGE(src, dst, i) \
  for (int _src = (src), _src2 = _src * 2, _dst2 = (dst)*2, _error = _dst2 - _src, i = 0, _delta; \
       ((void)(_delta = divide_floor_i(_error, _dst2)), (void)(i -= _delta), (i < _src)); \
       _error -= (_delta * _dst2) + _src2)
File headers: SPDX License migration Use a shorter/simpler license convention, stops the header taking so much space. Follow the SPDX license specification: https://spdx.org/licenses - C/C++/objc/objc++ - Python - Shell Scripts - CMake, GNUmakefile While most of the source tree has been included - `./extern/` was left out. - `./intern/cycles` & `./intern/atomic` are also excluded because they use different header conventions. doc/license/SPDX-license-identifiers.txt has been added to list SPDX all used identifiers. See P2788 for the script that automated these edits. Reviewed By: brecht, mont29, sergey Ref D14069 2022-02-11 09:07:11 +11:00			`/* SPDX-License-Identifier: GPL-2.0-or-later */`
BLI_utildefines_iter: Use for iteration helpers 2017-09-19 20:21:52 +10:00
			`#pragma once`

doxygen: add newline after \file While \file doesn't need an argument, it can't have another doxy command after it. 2019-02-18 08:08:12 +11:00			`/** \file`
			`* \ingroup bli`
BLI_utildefines_iter: Use for iteration helpers 2017-09-19 20:21:52 +10:00			`*`
			* General looping helpers, use `BLI_FOREACH` prefix.
			`*/`

			`/**`
			`* Even value distribution.`
			`*`
			`* \a src must be larger than \a dst,`
			`* \a dst defines the number of iterations, their values are evenly spaced.`
			`*`
			`* The following pairs represent (src, dst) arguments and the values they loop over.`
			`* <pre>`
			`* (19, 4) -> [2, 7, 11. 16]`
			`* (100, 5) -> [9, 29, 49, 69, 89]`
			`* (100, 3) -> [16, 49, 83]`
			`* (100, 100) -> [0..99]`
			`* </pre>`
			`* \note this is mainly useful for numbers that might not divide evenly into eachother.`
			`*/`
			`#define BLI_FOREACH_SPARSE_RANGE(src, dst, i) \`
			`for (int _src = (src), _src2 = _src * 2, _dst2 = (dst)*2, _error = _dst2 - _src, i = 0, _delta; \`
			`((void)(_delta = divide_floor_i(_error, _dst2)), (void)(i -= _delta), (i < _src)); \`
			`_error -= (_delta * _dst2) + _src2)`