[pulseview.git] / pv / data / logicsnapshot.cpp

/*
 * This file is part of the PulseView project.
 *
 * Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
 */

#include <extdef.h>

#include <assert.h>
#include <string.h>
#include <stdlib.h>
#include <math.h>

#include "config.h"
#include "logicsnapshot.h"

#include <libsigrok/libsigrok.hpp>

using std::lock_guard;
using std::recursive_mutex;
using std::max;
using std::min;
using std::pair;
using std::shared_ptr;

using sigrok::Logic;

namespace pv {
namespace data {

const int LogicSnapshot::MipMapScalePower = 4;
const int LogicSnapshot::MipMapScaleFactor = 1 << MipMapScalePower;
const float LogicSnapshot::LogMipMapScaleFactor = logf(MipMapScaleFactor);
const uint64_t LogicSnapshot::MipMapDataUnit = 64*1024;	// bytes

LogicSnapshot::LogicSnapshot(shared_ptr<Logic> logic,
                             const uint64_t expected_num_samples) :
	Snapshot(logic->unit_size()),
	_last_append_sample(0)
{
	set_capacity(expected_num_samples);

	lock_guard<recursive_mutex> lock(_mutex);
	memset(_mip_map, 0, sizeof(_mip_map));
	append_payload(logic);
}

LogicSnapshot::~LogicSnapshot()
{
	lock_guard<recursive_mutex> lock(_mutex);
	for (MipMapLevel &l : _mip_map)
		free(l.data);
}

uint64_t LogicSnapshot::unpack_sample(const uint8_t *ptr) const
{
#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
	return *(uint64_t*)ptr;
#else
	uint64_t value = 0;
	switch(_unit_size) {
	default:
		value |= ((uint64_t)ptr[7]) << 56;
		/* FALLTHRU */
	case 7:
		value |= ((uint64_t)ptr[6]) << 48;
		/* FALLTHRU */
	case 6:
		value |= ((uint64_t)ptr[5]) << 40;
		/* FALLTHRU */
	case 5:
		value |= ((uint64_t)ptr[4]) << 32;
		/* FALLTHRU */
	case 4:
		value |= ((uint32_t)ptr[3]) << 24;
		/* FALLTHRU */
	case 3:
		value |= ((uint32_t)ptr[2]) << 16;
		/* FALLTHRU */
	case 2:
		value |= ptr[1] << 8;
		/* FALLTHRU */
	case 1:
		value |= ptr[0];
		/* FALLTHRU */
	case 0:
		break;
	}
	return value;
#endif
}

void LogicSnapshot::pack_sample(uint8_t *ptr, uint64_t value)
{
#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
	*(uint64_t*)ptr = value;
#else
	switch(_unit_size) {
	default:
		ptr[7] = value >> 56;
		/* FALLTHRU */
	case 7:
		ptr[6] = value >> 48;
		/* FALLTHRU */
	case 6:
		ptr[5] = value >> 40;
		/* FALLTHRU */
	case 5:
		ptr[4] = value >> 32;
		/* FALLTHRU */
	case 4:
		ptr[3] = value >> 24;
		/* FALLTHRU */
	case 3:
		ptr[2] = value >> 16;
		/* FALLTHRU */
	case 2:
		ptr[1] = value >> 8;
		/* FALLTHRU */
	case 1:
		ptr[0] = value;
		/* FALLTHRU */
	case 0:
		break;
	}
#endif
}

void LogicSnapshot::append_payload(shared_ptr<Logic> logic)
{
	assert(_unit_size == logic->unit_size());
	assert((logic->data_length() % _unit_size) == 0);

	lock_guard<recursive_mutex> lock(_mutex);

	append_data(logic->data_pointer(),
		logic->data_length() / _unit_size);

	// Generate the first mip-map from the data
	append_payload_to_mipmap();
}

void LogicSnapshot::get_samples(uint8_t *const data,
	int64_t start_sample, int64_t end_sample) const
{
	assert(data);
	assert(start_sample >= 0);
	assert(start_sample <= (int64_t)_sample_count);
	assert(end_sample >= 0);
	assert(end_sample <= (int64_t)_sample_count);
	assert(start_sample <= end_sample);

	lock_guard<recursive_mutex> lock(_mutex);

	const size_t size = (end_sample - start_sample) * _unit_size;
	memcpy(data, (const uint8_t*)_data.data() + start_sample * _unit_size, size);
}

void LogicSnapshot::reallocate_mipmap_level(MipMapLevel &m)
{
	const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
		MipMapDataUnit) * MipMapDataUnit;
	if (new_data_length > m.data_length)
	{
		m.data_length = new_data_length;

		// Padding is added to allow for the uint64_t write word
		m.data = realloc(m.data, new_data_length * _unit_size +
			sizeof(uint64_t));
	}
}

void LogicSnapshot::append_payload_to_mipmap()
{
	MipMapLevel &m0 = _mip_map[0];
	uint64_t prev_length;
	const uint8_t *src_ptr;
	uint8_t *dest_ptr;
	uint64_t accumulator;
	unsigned int diff_counter;

	// Expand the data buffer to fit the new samples
	prev_length = m0.length;
	m0.length = _sample_count / MipMapScaleFactor;

	// Break off if there are no new samples to compute
	if (m0.length == prev_length)
		return;

	reallocate_mipmap_level(m0);

	dest_ptr = (uint8_t*)m0.data + prev_length * _unit_size;

	// Iterate through the samples to populate the first level mipmap
	const uint8_t *const end_src_ptr = (uint8_t*)_data.data() +
		m0.length * _unit_size * MipMapScaleFactor;
	for (src_ptr = (uint8_t*)_data.data() +
		prev_length * _unit_size * MipMapScaleFactor;
		src_ptr < end_src_ptr;)
	{
		// Accumulate transitions which have occurred in this sample
		accumulator = 0;
		diff_counter = MipMapScaleFactor;
		while (diff_counter-- > 0)
		{
			const uint64_t sample = unpack_sample(src_ptr);
			accumulator |= _last_append_sample ^ sample;
			_last_append_sample = sample;
			src_ptr += _unit_size;
		}

		pack_sample(dest_ptr, accumulator);
		dest_ptr += _unit_size;
	}

	// Compute higher level mipmaps
	for (unsigned int level = 1; level < ScaleStepCount; level++)
	{
		MipMapLevel &m = _mip_map[level];
		const MipMapLevel &ml = _mip_map[level-1];

		// Expand the data buffer to fit the new samples
		prev_length = m.length;
		m.length = ml.length / MipMapScaleFactor;

		// Break off if there are no more samples to computed
		if (m.length == prev_length)
			break;

		reallocate_mipmap_level(m);

		// Subsample the level lower level
		src_ptr = (uint8_t*)ml.data +
			_unit_size * prev_length * MipMapScaleFactor;
		const uint8_t *const end_dest_ptr =
			(uint8_t*)m.data + _unit_size * m.length;
		for (dest_ptr = (uint8_t*)m.data +
			_unit_size * prev_length;
			dest_ptr < end_dest_ptr;
			dest_ptr += _unit_size)
		{
			accumulator = 0;
			diff_counter = MipMapScaleFactor;
			while (diff_counter-- > 0)
			{
				accumulator |= unpack_sample(src_ptr);
				src_ptr += _unit_size;
			}

			pack_sample(dest_ptr, accumulator);
		}
	}
}

uint64_t LogicSnapshot::get_sample(uint64_t index) const
{
	assert(index < _sample_count);

	return unpack_sample((uint8_t*)_data.data() + index * _unit_size);
}

void LogicSnapshot::get_subsampled_edges(
	std::vector<EdgePair> &edges,
	uint64_t start, uint64_t end,
	float min_length, int sig_index)
{
	uint64_t index = start;
	unsigned int level;
	bool last_sample;
	bool fast_forward;

	assert(end <= get_sample_count());
	assert(start <= end);
	assert(min_length > 0);
	assert(sig_index >= 0);
	assert(sig_index < 64);

	lock_guard<recursive_mutex> lock(_mutex);

	const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
	const unsigned int min_level = max((int)floorf(logf(min_length) /
		LogMipMapScaleFactor) - 1, 0);
	const uint64_t sig_mask = 1ULL << sig_index;

	// Store the initial state
	last_sample = (get_sample(start) & sig_mask) != 0;
	edges.push_back(pair<int64_t, bool>(index++, last_sample));

	while (index + block_length <= end)
	{
		//----- Continue to search -----//
		level = min_level;

		// We cannot fast-forward if there is no mip-map data at
		// at the minimum level.
		fast_forward = (_mip_map[level].data != NULL);

		if (min_length < MipMapScaleFactor)
		{
			// Search individual samples up to the beginning of
			// the next first level mip map block
			const uint64_t final_index = min(end,
				pow2_ceil(index, MipMapScalePower));

			for (; index < final_index &&
				(index & ~(~0 << MipMapScalePower)) != 0;
				index++)
			{
				const bool sample =
					(get_sample(index) & sig_mask) != 0;

				// If there was a change we cannot fast forward
				if (sample != last_sample) {
					fast_forward = false;
					break;
				}
			}
		}
		else
		{
			// If resolution is less than a mip map block,
			// round up to the beginning of the mip-map block
			// for this level of detail
			const int min_level_scale_power =
				(level + 1) * MipMapScalePower;
			index = pow2_ceil(index, min_level_scale_power);
			if (index >= end)
				break;

			// We can fast forward only if there was no change
			const bool sample =
				(get_sample(index) & sig_mask) != 0;
			if (last_sample != sample)
				fast_forward = false;
		}

		if (fast_forward) {

			// Fast forward: This involves zooming out to higher
			// levels of the mip map searching for changes, then
			// zooming in on them to find the point where the edge
			// begins.

			// Slide right and zoom out at the beginnings of mip-map
			// blocks until we encounter a change
			while (1) {
				const int level_scale_power =
					(level + 1) * MipMapScalePower;
				const uint64_t offset =
					index >> level_scale_power;

				// Check if we reached the last block at this
				// level, or if there was a change in this block
				if (offset >= _mip_map[level].length ||
					(get_subsample(level, offset) &
						sig_mask))
					break;

				if ((offset & ~(~0 << MipMapScalePower)) == 0) {
					// If we are now at the beginning of a
					// higher level mip-map block ascend one
					// level
					if (level + 1 >= ScaleStepCount ||
						!_mip_map[level + 1].data)
						break;

					level++;
				} else {
					// Slide right to the beginning of the
					// next mip map block
					index = pow2_ceil(index + 1,
						level_scale_power);
				}
			}

			// Zoom in, and slide right until we encounter a change,
			// and repeat until we reach min_level
			while (1) {
				assert(_mip_map[level].data);

				const int level_scale_power =
					(level + 1) * MipMapScalePower;
				const uint64_t offset =
					index >> level_scale_power;

				// Check if we reached the last block at this
				// level, or if there was a change in this block
				if (offset >= _mip_map[level].length ||
					(get_subsample(level, offset) &
						sig_mask)) {
					// Zoom in unless we reached the minimum
					// zoom
					if (level == min_level)
						break;

					level--;
				} else {
					// Slide right to the beginning of the
					// next mip map block
					index = pow2_ceil(index + 1,
						level_scale_power);
				}
			}

			// If individual samples within the limit of resolution,
			// do a linear search for the next transition within the
			// block
			if (min_length < MipMapScaleFactor) {
				for (; index < end; index++) {
					const bool sample = (get_sample(index) &
						sig_mask) != 0;
					if (sample != last_sample)
						break;
				}
			}
		}

		//----- Store the edge -----//

		// Take the last sample of the quanization block
		const int64_t final_index = index + block_length;
		if (index + block_length > end)
			break;

		// Store the final state
		const bool final_sample =
			(get_sample(final_index - 1) & sig_mask) != 0;
		edges.push_back(pair<int64_t, bool>(index, final_sample));

		index = final_index;
		last_sample = final_sample;
	}

	// Add the final state
	const bool end_sample = get_sample(end) & sig_mask;
	if (last_sample != end_sample)
		edges.push_back(pair<int64_t, bool>(end, end_sample));
	edges.push_back(pair<int64_t, bool>(end + 1, end_sample));
}

uint64_t LogicSnapshot::get_subsample(int level, uint64_t offset) const
{
	assert(level >= 0);
	assert(_mip_map[level].data);
	return unpack_sample((uint8_t*)_mip_map[level].data +
		_unit_size * offset);
}

uint64_t LogicSnapshot::pow2_ceil(uint64_t x, unsigned int power)
{
	const uint64_t p = 1 << power;
	return (x + p - 1) / p * p;
}

} // namespace data
} // namespace pv
Commit	Line	Data
28a4c9c5	1	/*
b3f22de0	2	* This file is part of the PulseView project.
28a4c9c5 JH	3	*
	4	* Copyright (C) 2012 Joel Holdsworth <joel@airwebreathe.org.uk>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2 of the License, or
	9	* (at your option) any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	19	*/
	20
cef18fc6	21	#include <extdef.h>
28a4c9c5	22
f556bc6a	23	#include <assert.h>
4ceab49a	24	#include <string.h>
b36d8550	25	#include <stdlib.h>
4ceab49a JH	26	#include <math.h>
4ceab49a JH	27
9df8453f	28	#include "config.h"
1b1ec774	29	#include "logicsnapshot.h"
f556bc6a	30
e8d00928 ML	31	#include <libsigrok/libsigrok.hpp>
e8d00928 ML	32
3b68d03d JH	33	using std::lock_guard;
3b68d03d JH	34	using std::recursive_mutex;
819f4c25 JH	35	using std::max;
	36	using std::min;
	37	using std::pair;
e8d00928 ML	38	using std::shared_ptr;
	39
	40	using sigrok::Logic;
28a4c9c5	41
51e77110	42	namespace pv {
1b1ec774	43	namespace data {
51e77110	44
1b1ec774 JH	45	const int LogicSnapshot::MipMapScalePower = 4;
	46	const int LogicSnapshot::MipMapScaleFactor = 1 << MipMapScalePower;
	47	const float LogicSnapshot::LogMipMapScaleFactor = logf(MipMapScaleFactor);
	48	const uint64_t LogicSnapshot::MipMapDataUnit = 64*1024; // bytes
4ceab49a	49
e8d00928	50	LogicSnapshot::LogicSnapshot(shared_ptr<Logic> logic,
27d7c96b	51	const uint64_t expected_num_samples) :
e8d00928	52	Snapshot(logic->unit_size()),
4ceab49a	53	_last_append_sample(0)
f556bc6a	54	{
27d7c96b DK	55	set_capacity(expected_num_samples);
27d7c96b DK	56
7d29656f	57	lock_guard<recursive_mutex> lock(_mutex);
4ceab49a	58	memset(_mip_map, 0, sizeof(_mip_map));
f556bc6a JH	59	append_payload(logic);
	60	}
	61
1b1ec774	62	LogicSnapshot::~LogicSnapshot()
4ceab49a	63	{
7d29656f	64	lock_guard<recursive_mutex> lock(_mutex);
d9aecf1f	65	for (MipMapLevel &l : _mip_map)
4ceab49a JH	66	free(l.data);
	67	}
	68
8cb71705 MC	69	uint64_t LogicSnapshot::unpack_sample(const uint8_t *ptr) const
8cb71705 MC	70	{
9df8453f MC	71	#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
	72	return (uint64_t)ptr;
	73	#else
8cb71705 MC	74	uint64_t value = 0;
	75	switch(_unit_size) {
	76	default:
	77	value \|= ((uint64_t)ptr[7]) << 56;
	78	/* FALLTHRU */
	79	case 7:
	80	value \|= ((uint64_t)ptr[6]) << 48;
	81	/* FALLTHRU */
	82	case 6:
	83	value \|= ((uint64_t)ptr[5]) << 40;
	84	/* FALLTHRU */
	85	case 5:
	86	value \|= ((uint64_t)ptr[4]) << 32;
	87	/* FALLTHRU */
	88	case 4:
	89	value \|= ((uint32_t)ptr[3]) << 24;
	90	/* FALLTHRU */
	91	case 3:
	92	value \|= ((uint32_t)ptr[2]) << 16;
	93	/* FALLTHRU */
	94	case 2:
	95	value \|= ptr[1] << 8;
	96	/* FALLTHRU */
	97	case 1:
	98	value \|= ptr[0];
	99	/* FALLTHRU */
	100	case 0:
	101	break;
	102	}
	103	return value;
9df8453f	104	#endif
8cb71705 MC	105	}
	106
	107	void LogicSnapshot::pack_sample(uint8_t *ptr, uint64_t value)
	108	{
9df8453f MC	109	#ifdef HAVE_UNALIGNED_LITTLE_ENDIAN_ACCESS
	110	(uint64_t)ptr = value;
	111	#else
8cb71705 MC	112	switch(_unit_size) {
	113	default:
	114	ptr[7] = value >> 56;
	115	/* FALLTHRU */
	116	case 7:
	117	ptr[6] = value >> 48;
	118	/* FALLTHRU */
	119	case 6:
	120	ptr[5] = value >> 40;
	121	/* FALLTHRU */
	122	case 5:
	123	ptr[4] = value >> 32;
	124	/* FALLTHRU */
	125	case 4:
	126	ptr[3] = value >> 24;
	127	/* FALLTHRU */
	128	case 3:
	129	ptr[2] = value >> 16;
	130	/* FALLTHRU */
	131	case 2:
	132	ptr[1] = value >> 8;
	133	/* FALLTHRU */
	134	case 1:
	135	ptr[0] = value;
	136	/* FALLTHRU */
	137	case 0:
	138	break;
	139	}
9df8453f	140	#endif
8cb71705 MC	141	}
8cb71705 MC	142
e8d00928	143	void LogicSnapshot::append_payload(shared_ptr<Logic> logic)
28a4c9c5	144	{
e8d00928 ML	145	assert(_unit_size == logic->unit_size());
e8d00928 ML	146	assert((logic->data_length() % _unit_size) == 0);
f556bc6a	147
7d29656f JH	148	lock_guard<recursive_mutex> lock(_mutex);
7d29656f JH	149
e8d00928 ML	150	append_data(logic->data_pointer(),
e8d00928 ML	151	logic->data_length() / _unit_size);
4ceab49a JH	152
	153	// Generate the first mip-map from the data
	154	append_payload_to_mipmap();
	155	}
	156
ed990f11 JH	157	void LogicSnapshot::get_samples(uint8_t *const data,
	158	int64_t start_sample, int64_t end_sample) const
	159	{
	160	assert(data);
	161	assert(start_sample >= 0);
0fbda3c2	162	assert(start_sample <= (int64_t)_sample_count);
ed990f11	163	assert(end_sample >= 0);
0fbda3c2	164	assert(end_sample <= (int64_t)_sample_count);
ed990f11 JH	165	assert(start_sample <= end_sample);
	166
	167	lock_guard<recursive_mutex> lock(_mutex);
	168
	169	const size_t size = (end_sample - start_sample) * _unit_size;
c82c7e4e	170	memcpy(data, (const uint8_t)_data.data() + start_sample _unit_size, size);
ed990f11 JH	171	}
ed990f11 JH	172
023887ca	173	void LogicSnapshot::reallocate_mipmap_level(MipMapLevel &m)
4ceab49a JH	174	{
	175	const uint64_t new_data_length = ((m.length + MipMapDataUnit - 1) /
	176	MipMapDataUnit) * MipMapDataUnit;
333d5bbc	177	if (new_data_length > m.data_length)
4ceab49a JH	178	{
4ceab49a JH	179	m.data_length = new_data_length;
8fe60279 JH	180
	181	// Padding is added to allow for the uint64_t write word
	182	m.data = realloc(m.data, new_data_length * _unit_size +
	183	sizeof(uint64_t));
4ceab49a JH	184	}
	185	}
	186
1b1ec774	187	void LogicSnapshot::append_payload_to_mipmap()
4ceab49a JH	188	{
	189	MipMapLevel &m0 = _mip_map[0];
	190	uint64_t prev_length;
	191	const uint8_t *src_ptr;
	192	uint8_t *dest_ptr;
	193	uint64_t accumulator;
	194	unsigned int diff_counter;
	195
	196	// Expand the data buffer to fit the new samples
	197	prev_length = m0.length;
77bff0b1	198	m0.length = _sample_count / MipMapScaleFactor;
4ceab49a JH	199
4ceab49a JH	200	// Break off if there are no new samples to compute
333d5bbc	201	if (m0.length == prev_length)
4ceab49a JH	202	return;
4ceab49a JH	203
023887ca	204	reallocate_mipmap_level(m0);
4ceab49a JH	205
	206	dest_ptr = (uint8_t)m0.data + prev_length _unit_size;
	207
	208	// Iterate through the samples to populate the first level mipmap
c82c7e4e	209	const uint8_t const end_src_ptr = (uint8_t)_data.data() +
4ceab49a	210	m0.length * _unit_size * MipMapScaleFactor;
c82c7e4e	211	for (src_ptr = (uint8_t*)_data.data() +
4ceab49a JH	212	prev_length * _unit_size * MipMapScaleFactor;
	213	src_ptr < end_src_ptr;)
	214	{
	215	// Accumulate transitions which have occurred in this sample
	216	accumulator = 0;
	217	diff_counter = MipMapScaleFactor;
333d5bbc	218	while (diff_counter-- > 0)
4ceab49a	219	{
8cb71705	220	const uint64_t sample = unpack_sample(src_ptr);
4ceab49a JH	221	accumulator \|= _last_append_sample ^ sample;
	222	_last_append_sample = sample;
	223	src_ptr += _unit_size;
	224	}
	225
8cb71705	226	pack_sample(dest_ptr, accumulator);
4ceab49a JH	227	dest_ptr += _unit_size;
	228	}
	229
	230	// Compute higher level mipmaps
333d5bbc	231	for (unsigned int level = 1; level < ScaleStepCount; level++)
4ceab49a JH	232	{
	233	MipMapLevel &m = _mip_map[level];
	234	const MipMapLevel &ml = _mip_map[level-1];
	235
	236	// Expand the data buffer to fit the new samples
	237	prev_length = m.length;
	238	m.length = ml.length / MipMapScaleFactor;
	239
	240	// Break off if there are no more samples to computed
333d5bbc	241	if (m.length == prev_length)
4ceab49a JH	242	break;
4ceab49a JH	243
023887ca	244	reallocate_mipmap_level(m);
4ceab49a JH	245
	246	// Subsample the level lower level
	247	src_ptr = (uint8_t*)ml.data +
	248	_unit_size * prev_length * MipMapScaleFactor;
023887ca	249	const uint8_t *const end_dest_ptr =
4ceab49a	250	(uint8_t)m.data + _unit_size m.length;
333d5bbc	251	for (dest_ptr = (uint8_t*)m.data +
4ceab49a JH	252	_unit_size * prev_length;
	253	dest_ptr < end_dest_ptr;
	254	dest_ptr += _unit_size)
	255	{
	256	accumulator = 0;
	257	diff_counter = MipMapScaleFactor;
333d5bbc	258	while (diff_counter-- > 0)
4ceab49a	259	{
8cb71705	260	accumulator \|= unpack_sample(src_ptr);
4ceab49a JH	261	src_ptr += _unit_size;
	262	}
	263
8cb71705	264	pack_sample(dest_ptr, accumulator);
4ceab49a JH	265	}
4ceab49a JH	266	}
28a4c9c5	267	}
2858b391	268
1b1ec774	269	uint64_t LogicSnapshot::get_sample(uint64_t index) const
2858b391	270	{
3f96c34a	271	assert(index < _sample_count);
2858b391	272
c82c7e4e	273	return unpack_sample((uint8_t)_data.data() + index _unit_size);
2858b391 JH	274	}
2858b391 JH	275
1b1ec774	276	void LogicSnapshot::get_subsampled_edges(
2858b391	277	std::vector<EdgePair> &edges,
60b0c2da	278	uint64_t start, uint64_t end,
0b02e057	279	float min_length, int sig_index)
2858b391	280	{
60b0c2da JH	281	uint64_t index = start;
60b0c2da JH	282	unsigned int level;
7d0d64f9 JH	283	bool last_sample;
7d0d64f9 JH	284	bool fast_forward;
0b02e057	285
0b02e057	286	assert(end <= get_sample_count());
2858b391	287	assert(start <= end);
0b02e057	288	assert(min_length > 0);
2858b391	289	assert(sig_index >= 0);
80d50141	290	assert(sig_index < 64);
2858b391	291
7d29656f JH	292	lock_guard<recursive_mutex> lock(_mutex);
7d29656f JH	293
60b0c2da JH	294	const uint64_t block_length = (uint64_t)max(min_length, 1.0f);
60b0c2da JH	295	const unsigned int min_level = max((int)floorf(logf(min_length) /
0b02e057	296	LogMipMapScaleFactor) - 1, 0);
7d0d64f9	297	const uint64_t sig_mask = 1ULL << sig_index;
2858b391	298
7d0d64f9 JH	299	// Store the initial state
	300	last_sample = (get_sample(start) & sig_mask) != 0;
	301	edges.push_back(pair<int64_t, bool>(index++, last_sample));
2858b391	302
333d5bbc	303	while (index + block_length <= end)
2858b391	304	{
7d0d64f9	305	//----- Continue to search -----//
0b02e057	306	level = min_level;
f06ab143 JH	307
	308	// We cannot fast-forward if there is no mip-map data at
	309	// at the minimum level.
	310	fast_forward = (_mip_map[level].data != NULL);
2858b391	311
333d5bbc	312	if (min_length < MipMapScaleFactor)
0b02e057 JH	313	{
	314	// Search individual samples up to the beginning of
	315	// the next first level mip map block
7d0d64f9	316	const uint64_t final_index = min(end,
0b02e057 JH	317	pow2_ceil(index, MipMapScalePower));
0b02e057 JH	318
333d5bbc	319	for (; index < final_index &&
0b02e057 JH	320	(index & ~(~0 << MipMapScalePower)) != 0;
	321	index++)
	322	{
	323	const bool sample =
	324	(get_sample(index) & sig_mask) != 0;
7d0d64f9 JH	325
7d0d64f9 JH	326	// If there was a change we cannot fast forward
333d5bbc	327	if (sample != last_sample) {
7d0d64f9	328	fast_forward = false;
0b02e057	329	break;
7d0d64f9	330	}
0b02e057 JH	331	}
	332	}
	333	else
	334	{
	335	// If resolution is less than a mip map block,
	336	// round up to the beginning of the mip-map block
	337	// for this level of detail
	338	const int min_level_scale_power =
	339	(level + 1) * MipMapScalePower;
	340	index = pow2_ceil(index, min_level_scale_power);
333d5bbc	341	if (index >= end)
0b02e057 JH	342	break;
0b02e057 JH	343
7d0d64f9 JH	344	// We can fast forward only if there was no change
	345	const bool sample =
	346	(get_sample(index) & sig_mask) != 0;
f06ab143 JH	347	if (last_sample != sample)
f06ab143 JH	348	fast_forward = false;
0b02e057 JH	349	}
0b02e057 JH	350
333d5bbc	351	if (fast_forward) {
7d0d64f9 JH	352
	353	// Fast forward: This involves zooming out to higher
	354	// levels of the mip map searching for changes, then
	355	// zooming in on them to find the point where the edge
	356	// begins.
	357
	358	// Slide right and zoom out at the beginnings of mip-map
	359	// blocks until we encounter a change
333d5bbc	360	while (1) {
7d0d64f9 JH	361	const int level_scale_power =
	362	(level + 1) * MipMapScalePower;
	363	const uint64_t offset =
	364	index >> level_scale_power;
7d0d64f9 JH	365
	366	// Check if we reached the last block at this
	367	// level, or if there was a change in this block
333d5bbc	368	if (offset >= _mip_map[level].length \|\|
7d0d64f9 JH	369	(get_subsample(level, offset) &
7d0d64f9 JH	370	sig_mask))
0b02e057 JH	371	break;
0b02e057 JH	372
333d5bbc	373	if ((offset & ~(~0 << MipMapScalePower)) == 0) {
7d0d64f9 JH	374	// If we are now at the beginning of a
	375	// higher level mip-map block ascend one
	376	// level
333d5bbc	377	if (level + 1 >= ScaleStepCount \|\|
7d0d64f9 JH	378	!_mip_map[level + 1].data)
	379	break;
	380
	381	level++;
	382	} else {
	383	// Slide right to the beginning of the
	384	// next mip map block
	385	index = pow2_ceil(index + 1,
	386	level_scale_power);
	387	}
0b02e057	388	}
7d0d64f9 JH	389
	390	// Zoom in, and slide right until we encounter a change,
	391	// and repeat until we reach min_level
333d5bbc	392	while (1) {
7d0d64f9 JH	393	assert(_mip_map[level].data);
	394
	395	const int level_scale_power =
	396	(level + 1) * MipMapScalePower;
	397	const uint64_t offset =
	398	index >> level_scale_power;
7d0d64f9 JH	399
	400	// Check if we reached the last block at this
	401	// level, or if there was a change in this block
333d5bbc	402	if (offset >= _mip_map[level].length \|\|
7d0d64f9 JH	403	(get_subsample(level, offset) &
	404	sig_mask)) {
	405	// Zoom in unless we reached the minimum
	406	// zoom
333d5bbc	407	if (level == min_level)
7d0d64f9 JH	408	break;
	409
	410	level--;
	411	} else {
	412	// Slide right to the beginning of the
	413	// next mip map block
	414	index = pow2_ceil(index + 1,
	415	level_scale_power);
	416	}
0b02e057	417	}
0b02e057	418
7d0d64f9 JH	419	// If individual samples within the limit of resolution,
	420	// do a linear search for the next transition within the
	421	// block
333d5bbc UH	422	if (min_length < MipMapScaleFactor) {
333d5bbc UH	423	for (; index < end; index++) {
7d0d64f9 JH	424	const bool sample = (get_sample(index) &
7d0d64f9 JH	425	sig_mask) != 0;
333d5bbc	426	if (sample != last_sample)
7d0d64f9 JH	427	break;
7d0d64f9 JH	428	}
0b02e057 JH	429	}
	430	}
	431
7d0d64f9 JH	432	//----- Store the edge -----//
	433
	434	// Take the last sample of the quanization block
	435	const int64_t final_index = index + block_length;
333d5bbc	436	if (index + block_length > end)
7d0d64f9 JH	437	break;
	438
	439	// Store the final state
	440	const bool final_sample =
	441	(get_sample(final_index - 1) & sig_mask) != 0;
	442	edges.push_back(pair<int64_t, bool>(index, final_sample));
	443
	444	index = final_index;
	445	last_sample = final_sample;
2858b391 JH	446	}
	447
	448	// Add the final state
175d6573 JH	449	const bool end_sample = get_sample(end) & sig_mask;
	450	if (last_sample != end_sample)
	451	edges.push_back(pair<int64_t, bool>(end, end_sample));
	452	edges.push_back(pair<int64_t, bool>(end + 1, end_sample));
2858b391	453	}
0b02e057	454
1b1ec774	455	uint64_t LogicSnapshot::get_subsample(int level, uint64_t offset) const
b2bcbe51 JH	456	{
	457	assert(level >= 0);
	458	assert(_mip_map[level].data);
8cb71705	459	return unpack_sample((uint8_t*)_mip_map[level].data +
b2bcbe51 JH	460	_unit_size * offset);
	461	}
	462
1b1ec774	463	uint64_t LogicSnapshot::pow2_ceil(uint64_t x, unsigned int power)
0b02e057	464	{
60b0c2da JH	465	const uint64_t p = 1 << power;
60b0c2da JH	466	return (x + p - 1) / p * p;
0b02e057	467	}
51e77110	468
1b1ec774	469	} // namespace data
51e77110	470	} // namespace pv