* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#include "logicdatasnapshot.h"
+#include "extdef.h"
#include <assert.h>
+#include <string.h>
+#include <math.h>
+
+#include <boost/foreach.hpp>
+
+#include "logicdatasnapshot.h"
-#include <QDebug>
+using namespace std;
+
+const int LogicDataSnapshot::MipMapScalePower = 4;
+const int LogicDataSnapshot::MipMapScaleFactor = 1 << MipMapScalePower;
+const float LogicDataSnapshot::LogMipMapScaleFactor = logf(MipMapScaleFactor);
+const uint64_t LogicDataSnapshot::MipMapDataUnit = 64*1024; // bytes
LogicDataSnapshot::LogicDataSnapshot(
const sr_datafeed_logic &logic) :
- DataSnapshot(logic.unitsize)
+ DataSnapshot(logic.unitsize),
+ _last_append_sample(0)
{
+ memset(_mip_map, 0, sizeof(_mip_map));
append_payload(logic);
}
+LogicDataSnapshot::~LogicDataSnapshot()
+{
+ BOOST_FOREACH(MipMapLevel &l, _mip_map)
+ free(l.data);
+}
+
void LogicDataSnapshot::append_payload(
const sr_datafeed_logic &logic)
{
assert(_unit_size == logic.unitsize);
- qDebug() << "SR_DF_LOGIC (length =" << logic.length
- << ", unitsize = " << logic.unitsize << ")";
-
+ const uint64_t prev_length = _data_length;
append_data(logic.data, logic.length);
+
+ // Generate the first mip-map from the data
+ append_payload_to_mipmap();
+}
+
+void LogicDataSnapshot::reallocate_mip_map(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;
+ m.data = realloc(m.data, new_data_length * _unit_size);
+ }
+}
+
+void LogicDataSnapshot::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 = _data_length / MipMapScaleFactor;
+
+ // Break off if there are no new samples to compute
+ if(m0.length == prev_length)
+ return;
+
+ reallocate_mip_map(m0);
+
+ dest_ptr = (uint8_t*)m0.data + prev_length * _unit_size;
+
+ // Iterate through the samples to populate the first level mipmap
+ accumulator = 0;
+ diff_counter = MipMapScaleFactor;
+ const uint8_t *end_src_ptr = (uint8_t*)_data +
+ m0.length * _unit_size * MipMapScaleFactor;
+ for(src_ptr = (uint8_t*)_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 = *(uint64_t*)src_ptr;
+ accumulator |= _last_append_sample ^ sample;
+ _last_append_sample = sample;
+ src_ptr += _unit_size;
+ }
+
+ *(uint64_t*)dest_ptr = accumulator;
+ dest_ptr += _unit_size;
+ }
+
+ // Compute higher level mipmaps
+ for(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_mip_map(m);
+
+ // Subsample the level lower level
+ src_ptr = (uint8_t*)ml.data +
+ _unit_size * prev_length * MipMapScaleFactor;
+ const uint8_t *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 |= *(uint64_t*)src_ptr;
+ src_ptr += _unit_size;
+ }
+
+ *(uint64_t*)dest_ptr = accumulator;
+ }
+ }
+}
+
+uint64_t LogicDataSnapshot::get_sample(uint64_t index) const
+{
+ assert(_data);
+ assert(index >= 0 && index < _data_length);
+
+ return *(uint64_t*)((uint8_t*)_data + index * _unit_size);
+}
+
+void LogicDataSnapshot::get_subsampled_edges(
+ std::vector<EdgePair> &edges,
+ int64_t start, int64_t end,
+ float min_length, int sig_index)
+{
+ int64_t index;
+ int level;
+
+ assert(start >= 0);
+ assert(end <= get_sample_count());
+ assert(start <= end);
+ assert(min_length > 0);
+ assert(sig_index >= 0);
+ assert(sig_index < SR_MAX_NUM_PROBES);
+
+ const int min_level = max((int)floorf(logf(min_length) /
+ LogMipMapScaleFactor) - 1, 0);
+ const uint64_t sig_mask = 1 << sig_index;
+
+ // Add the initial state
+ bool last_sample = get_sample(start) & sig_mask;
+ edges.push_back(pair<int64_t, bool>(start, last_sample));
+
+ index = start + 1;
+ for(index = start + 1; index < end;)
+ {
+ level = min_level;
+
+ if(min_length < MipMapScaleFactor)
+ {
+ // Search individual samples up to the beginning of
+ // the next first level mip map block
+ const uint64_t final_sample = min(end,
+ pow2_ceil(index, MipMapScalePower));
+
+ for(index;
+ index < final_sample &&
+ (index & ~(~0 << MipMapScalePower)) != 0;
+ index++)
+ {
+ const bool sample =
+ (get_sample(index) & sig_mask) != 0;
+ if(sample != last_sample)
+ 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);
+ }
+
+ // 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;
+ assert(offset >= 0);
+
+ // 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 ||
+ (*(uint64_t*)((uint8_t*)_mip_map[level].data +
+ _unit_size * 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(!_mip_map[level + 1].data)
+ break;
+
+ level++;
+ }
+ else
+ {
+ // Slide right to the beginning of the next mip
+ // map block
+ index = pow2_ceil(index, 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;
+ assert(offset >= 0);
+
+ // 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 ||
+ (*(uint64_t*)((uint8_t*)_mip_map[level].data +
+ _unit_size * 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, 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; index < end; index++)
+ {
+ const bool sample =
+ (get_sample(index) & sig_mask) != 0;
+ if(sample != last_sample)
+ break;
+ }
+ }
+
+ if(index < end)
+ {
+ // Take the last sample of the quanization block
+ const int64_t block_length = (int64_t)max(min_length, 1.0f);
+ const int64_t rem = index % block_length;
+ const int64_t final_index = min(index + (rem == 0 ? 0 :
+ block_length - rem), end);
+
+ // Store the final state
+ const bool final_sample = get_sample(final_index) & sig_mask;
+ edges.push_back(pair<int64_t, bool>(
+ final_index, final_sample));
+
+ // Continue to sample
+ index = final_index;
+ last_sample = final_sample;
+
+ index++;
+ }
+ }
+
+ // Add the final state
+ edges.push_back(pair<int64_t, bool>(end,
+ get_sample(end) & sig_mask));
+}
+
+int64_t LogicDataSnapshot::pow2_ceil(int64_t x, unsigned int power)
+{
+ const int64_t p = 1 << power;
+ return ((x < 0) ? x : (x + p - 1)) / p * p;
}