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|
/*************************************************************************
* *
* Open Dynamics Engine, Copyright (C) 2001-2003 Russell L. Smith. *
* All rights reserved. Email: russ@q12.org Web: www.q12.org *
* *
* This library is free software; you can redistribute it and/or *
* modify it under the terms of EITHER: *
* (1) The GNU Lesser General Public License as published by the Free *
* Software Foundation; either version 2.1 of the License, or (at *
* your option) any later version. The text of the GNU Lesser *
* General Public License is included with this library in the *
* file LICENSE.TXT. *
* (2) The BSD-style license that is included with this library in *
* the file LICENSE-BSD.TXT. *
* *
* This library 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 files *
* LICENSE.TXT and LICENSE-BSD.TXT for more details. *
* *
*************************************************************************/
/*
* Sweep and Prune adaptation/tweaks for ODE by Aras Pranckevicius.
* Additional work by David Walters
* Original code:
* OPCODE - Optimized Collision Detection
* Copyright (C) 2001 Pierre Terdiman
* Homepage: http://www.codercorner.com/Opcode.htm
*
* This version does complete radix sort, not "classical" SAP. So, we
* have no temporal coherence, but are able to handle any movement
* velocities equally well.
*/
#include <ode/common.h>
#include <ode/collision_space.h>
#include <ode/collision.h>
#include "config.h"
#include "matrix.h"
#include "collision_kernel.h"
#include "collision_space_internal.h"
// Reference counting helper for radix sort global data.
//static void RadixSortRef();
//static void RadixSortDeref();
// --------------------------------------------------------------------------
// Radix Sort Context
// --------------------------------------------------------------------------
struct RaixSortContext
{
public:
RaixSortContext(): mCurrentSize(0), mCurrentUtilization(0), mRanksValid(false), mRanksBuffer(NULL), mPrimaryRanks(NULL) {}
~RaixSortContext() { FreeRanks(); }
// OPCODE's Radix Sorting, returns a list of indices in sorted order
const uint32* RadixSort( const float* input2, uint32 nb );
private:
void FreeRanks();
void AllocateRanks(sizeint nNewSize);
void ReallocateRanksIfNecessary(sizeint nNewSize);
private:
void SetCurrentSize(sizeint nValue) { mCurrentSize = nValue; }
sizeint GetCurrentSize() const { return mCurrentSize; }
void SetCurrentUtilization(sizeint nValue) { mCurrentUtilization = nValue; }
sizeint GetCurrentUtilization() const { return mCurrentUtilization; }
uint32 *GetRanks1() const { return mPrimaryRanks; }
uint32 *GetRanks2() const { return mRanksBuffer + ((mRanksBuffer + mCurrentSize) - mPrimaryRanks); }
void SwapRanks() { mPrimaryRanks = GetRanks2(); }
bool AreRanksValid() const { return mRanksValid; }
void InvalidateRanks() { mRanksValid = false; }
void ValidateRanks() { mRanksValid = true; }
private:
sizeint mCurrentSize; //!< Current size of the indices list
sizeint mCurrentUtilization; //!< Current utilization of the indices list
bool mRanksValid;
uint32* mRanksBuffer; //!< Two lists allocated sequentially in a single block
uint32* mPrimaryRanks;
};
void RaixSortContext::AllocateRanks(sizeint nNewSize)
{
dIASSERT(GetCurrentSize() == 0);
mRanksBuffer = new uint32[2 * nNewSize];
mPrimaryRanks = mRanksBuffer;
SetCurrentSize(nNewSize);
}
void RaixSortContext::FreeRanks()
{
SetCurrentSize(0);
delete[] mRanksBuffer;
}
void RaixSortContext::ReallocateRanksIfNecessary(sizeint nNewSize)
{
sizeint nCurUtilization = GetCurrentUtilization();
if (nNewSize != nCurUtilization)
{
sizeint nCurSize = GetCurrentSize();
if ( nNewSize > nCurSize )
{
// Free previously used ram
FreeRanks();
// Get some fresh one
AllocateRanks(nNewSize);
}
InvalidateRanks();
SetCurrentUtilization(nNewSize);
}
}
// --------------------------------------------------------------------------
// SAP space code
// --------------------------------------------------------------------------
struct dxSAPSpace : public dxSpace
{
// Constructor / Destructor
dxSAPSpace( dSpaceID _space, int sortaxis );
~dxSAPSpace();
// dxSpace
virtual dxGeom* getGeom(int i);
virtual void add(dxGeom* g);
virtual void remove(dxGeom* g);
virtual void dirty(dxGeom* g);
virtual void computeAABB();
virtual void cleanGeoms();
virtual void collide( void *data, dNearCallback *callback );
virtual void collide2( void *data, dxGeom *geom, dNearCallback *callback );
private:
//--------------------------------------------------------------------------
// Local Declarations
//--------------------------------------------------------------------------
//! A generic couple structure
struct Pair
{
uint32 id0; //!< First index of the pair
uint32 id1; //!< Second index of the pair
// Default and Value Constructor
Pair() {}
Pair( uint32 i0, uint32 i1 ) : id0( i0 ), id1( i1 ) {}
};
//--------------------------------------------------------------------------
// Helpers
//--------------------------------------------------------------------------
/**
* Complete box pruning.
* Returns a list of overlapping pairs of boxes, each box of the pair
* belongs to the same set.
*
* @param count [in] number of boxes.
* @param geoms [in] geoms of boxes.
* @param pairs [out] array of overlapping pairs.
*/
void BoxPruning( int count, const dxGeom** geoms, dArray< Pair >& pairs );
//--------------------------------------------------------------------------
// Implementation Data
//--------------------------------------------------------------------------
// We have two lists (arrays of pointers) to dirty and clean
// geoms. Each geom knows it's index into the corresponding list
// (see macros above).
dArray<dxGeom*> DirtyList; // dirty geoms
dArray<dxGeom*> GeomList; // clean geoms
// For SAP, we ultimately separate "normal" geoms and the ones that have
// infinite AABBs. No point doing SAP on infinite ones (and it doesn't handle
// infinite geoms anyway).
dArray<dxGeom*> TmpGeomList; // temporary for normal geoms
dArray<dxGeom*> TmpInfGeomList; // temporary for geoms with infinite AABBs
// Our sorting axes. (X,Z,Y is often best). Stored *2 for minor speedup
// Axis indices into geom's aabb are: min=idx, max=idx+1
uint32 ax0idx;
uint32 ax1idx;
uint32 ax2idx;
// pruning position array scratch pad
// NOTE: this is float not dReal because of the OPCODE radix sorter
dArray< float > poslist;
RaixSortContext sortContext;
};
// Creation
dSpaceID dSweepAndPruneSpaceCreate( dxSpace* space, int axisorder ) {
return new dxSAPSpace( space, axisorder );
}
//==============================================================================
#define GEOM_ENABLED(g) (((g)->gflags & GEOM_ENABLE_TEST_MASK) == GEOM_ENABLE_TEST_VALUE)
// HACK: We abuse 'next' and 'tome' members of dxGeom to store indices into dirty/geom lists.
#define GEOM_SET_DIRTY_IDX(g,idx) { (g)->next_ex = (dxGeom*)(sizeint)(idx); }
#define GEOM_SET_GEOM_IDX(g,idx) { (g)->tome_ex = (dxGeom**)(sizeint)(idx); }
#define GEOM_GET_DIRTY_IDX(g) ((int)(sizeint)(g)->next_ex)
#define GEOM_GET_GEOM_IDX(g) ((int)(sizeint)(g)->tome_ex)
#define GEOM_INVALID_IDX (-1)
/*
* A bit of repetitive work - similar to collideAABBs, but doesn't check
* if AABBs intersect (because SAP returns pairs with overlapping AABBs).
*/
static void collideGeomsNoAABBs( dxGeom *g1, dxGeom *g2, void *data, dNearCallback *callback )
{
dIASSERT( (g1->gflags & GEOM_AABB_BAD)==0 );
dIASSERT( (g2->gflags & GEOM_AABB_BAD)==0 );
// no contacts if both geoms on the same body, and the body is not 0
if (g1->body == g2->body && g1->body) return;
// test if the category and collide bitfields match
if ( ((g1->category_bits & g2->collide_bits) ||
(g2->category_bits & g1->collide_bits)) == 0) {
return;
}
dReal *bounds1 = g1->aabb;
dReal *bounds2 = g2->aabb;
// check if either object is able to prove that it doesn't intersect the
// AABB of the other
if (g1->AABBTest (g2,bounds2) == 0) return;
if (g2->AABBTest (g1,bounds1) == 0) return;
// the objects might actually intersect - call the space callback function
callback (data,g1,g2);
}
dxSAPSpace::dxSAPSpace( dSpaceID _space, int axisorder ) : dxSpace( _space )
{
type = dSweepAndPruneSpaceClass;
// Init AABB to infinity
aabb[0] = -dInfinity;
aabb[1] = dInfinity;
aabb[2] = -dInfinity;
aabb[3] = dInfinity;
aabb[4] = -dInfinity;
aabb[5] = dInfinity;
ax0idx = ( ( axisorder ) & 3 ) << 1;
ax1idx = ( ( axisorder >> 2 ) & 3 ) << 1;
ax2idx = ( ( axisorder >> 4 ) & 3 ) << 1;
}
dxSAPSpace::~dxSAPSpace()
{
CHECK_NOT_LOCKED(this);
if ( cleanup ) {
// note that destroying each geom will call remove()
for ( ; DirtyList.size(); dGeomDestroy( DirtyList[ 0 ] ) ) {}
for ( ; GeomList.size(); dGeomDestroy( GeomList[ 0 ] ) ) {}
}
else {
// just unhook them
for ( ; DirtyList.size(); remove( DirtyList[ 0 ] ) ) {}
for ( ; GeomList.size(); remove( GeomList[ 0 ] ) ) {}
}
}
dxGeom* dxSAPSpace::getGeom( int i )
{
dUASSERT( i >= 0 && i < count, "index out of range" );
int dirtySize = DirtyList.size();
if( i < dirtySize )
return DirtyList[i];
else
return GeomList[i-dirtySize];
}
void dxSAPSpace::add( dxGeom* g )
{
CHECK_NOT_LOCKED (this);
dAASSERT(g);
dUASSERT(g->tome_ex == 0 && g->next_ex == 0, "geom is already in a space");
// add to dirty list
GEOM_SET_DIRTY_IDX( g, DirtyList.size() );
GEOM_SET_GEOM_IDX( g, GEOM_INVALID_IDX );
DirtyList.push( g );
dxSpace::add(g);
}
void dxSAPSpace::remove( dxGeom* g )
{
CHECK_NOT_LOCKED(this);
dAASSERT(g);
dUASSERT(g->parent_space == this,"object is not in this space");
// remove
int dirtyIdx = GEOM_GET_DIRTY_IDX(g);
int geomIdx = GEOM_GET_GEOM_IDX(g);
// must be in one list, not in both
dUASSERT(
(dirtyIdx==GEOM_INVALID_IDX && geomIdx>=0 && geomIdx<GeomList.size()) ||
(geomIdx==GEOM_INVALID_IDX && dirtyIdx>=0 && dirtyIdx<DirtyList.size()),
"geom indices messed up" );
if( dirtyIdx != GEOM_INVALID_IDX ) {
// we're in dirty list, remove
int dirtySize = DirtyList.size();
if (dirtyIdx != dirtySize-1) {
dxGeom* lastG = DirtyList[dirtySize-1];
DirtyList[dirtyIdx] = lastG;
GEOM_SET_DIRTY_IDX(lastG,dirtyIdx);
}
GEOM_SET_DIRTY_IDX(g,GEOM_INVALID_IDX);
DirtyList.setSize( dirtySize-1 );
} else {
// we're in geom list, remove
int geomSize = GeomList.size();
if (geomIdx != geomSize-1) {
dxGeom* lastG = GeomList[geomSize-1];
GeomList[geomIdx] = lastG;
GEOM_SET_GEOM_IDX(lastG,geomIdx);
}
GEOM_SET_GEOM_IDX(g,GEOM_INVALID_IDX);
GeomList.setSize( geomSize-1 );
}
dxSpace::remove(g);
}
void dxSAPSpace::dirty( dxGeom* g )
{
dAASSERT(g);
dUASSERT(g->parent_space == this, "object is not in this space");
// check if already dirtied
int dirtyIdx = GEOM_GET_DIRTY_IDX(g);
if( dirtyIdx != GEOM_INVALID_IDX )
return;
int geomIdx = GEOM_GET_GEOM_IDX(g);
dUASSERT( geomIdx>=0 && geomIdx<GeomList.size(), "geom indices messed up" );
// remove from geom list, place last in place of this
int geomSize = GeomList.size();
if (geomIdx != geomSize-1) {
dxGeom* lastG = GeomList[geomSize-1];
GeomList[geomIdx] = lastG;
GEOM_SET_GEOM_IDX(lastG,geomIdx);
}
GeomList.setSize( geomSize-1 );
// add to dirty list
GEOM_SET_GEOM_IDX( g, GEOM_INVALID_IDX );
GEOM_SET_DIRTY_IDX( g, DirtyList.size() );
DirtyList.push( g );
}
void dxSAPSpace::computeAABB()
{
// TODO?
}
void dxSAPSpace::cleanGeoms()
{
int dirtySize = DirtyList.size();
if( !dirtySize )
return;
// compute the AABBs of all dirty geoms, clear the dirty flags,
// remove from dirty list, place into geom list
lock_count++;
int geomSize = GeomList.size();
GeomList.setSize( geomSize + dirtySize ); // ensure space in geom list
for( int i = 0; i < dirtySize; ++i ) {
dxGeom* g = DirtyList[i];
if( IS_SPACE(g) ) {
((dxSpace*)g)->cleanGeoms();
}
g->recomputeAABB();
dIASSERT((g->gflags & GEOM_AABB_BAD) == 0);
g->gflags &= ~GEOM_DIRTY;
// remove from dirty list, add to geom list
GEOM_SET_DIRTY_IDX( g, GEOM_INVALID_IDX );
GEOM_SET_GEOM_IDX( g, geomSize + i );
GeomList[geomSize+i] = g;
}
// clear dirty list
DirtyList.setSize( 0 );
lock_count--;
}
void dxSAPSpace::collide( void *data, dNearCallback *callback )
{
dAASSERT (callback);
lock_count++;
cleanGeoms();
// by now all geoms are in GeomList, and DirtyList must be empty
int geom_count = GeomList.size();
dUASSERT( geom_count == count, "geom counts messed up" );
// separate all ENABLED geoms into infinite AABBs and normal AABBs
TmpGeomList.setSize(0);
TmpInfGeomList.setSize(0);
int axis0max = ax0idx + 1;
for( int i = 0; i < geom_count; ++i ) {
dxGeom* g = GeomList[i];
if( !GEOM_ENABLED(g) ) // skip disabled ones
continue;
const dReal& amax = g->aabb[axis0max];
if( amax == dInfinity ) // HACK? probably not...
TmpInfGeomList.push( g );
else
TmpGeomList.push( g );
}
// do SAP on normal AABBs
dArray< Pair > overlapBoxes;
int tmp_geom_count = TmpGeomList.size();
if ( tmp_geom_count > 0 )
{
// Generate a list of overlapping boxes
BoxPruning( tmp_geom_count, (const dxGeom**)TmpGeomList.data(), overlapBoxes );
}
// collide overlapping
int overlapCount = overlapBoxes.size();
for( int j = 0; j < overlapCount; ++j )
{
const Pair& pair = overlapBoxes[ j ];
dxGeom* g1 = TmpGeomList[ pair.id0 ];
dxGeom* g2 = TmpGeomList[ pair.id1 ];
collideGeomsNoAABBs( g1, g2, data, callback );
}
int infSize = TmpInfGeomList.size();
int normSize = TmpGeomList.size();
int m, n;
for ( m = 0; m < infSize; ++m )
{
dxGeom* g1 = TmpInfGeomList[ m ];
// collide infinite ones
for( n = m+1; n < infSize; ++n ) {
dxGeom* g2 = TmpInfGeomList[n];
collideGeomsNoAABBs( g1, g2, data, callback );
}
// collide infinite ones with normal ones
for( n = 0; n < normSize; ++n ) {
dxGeom* g2 = TmpGeomList[n];
collideGeomsNoAABBs( g1, g2, data, callback );
}
}
lock_count--;
}
void dxSAPSpace::collide2( void *data, dxGeom *geom, dNearCallback *callback )
{
dAASSERT (geom && callback);
// TODO: This is just a simple N^2 implementation
lock_count++;
cleanGeoms();
geom->recomputeAABB();
// intersect bounding boxes
int geom_count = GeomList.size();
for ( int i = 0; i < geom_count; ++i ) {
dxGeom* g = GeomList[i];
if ( GEOM_ENABLED(g) )
collideAABBs (g,geom,data,callback);
}
lock_count--;
}
void dxSAPSpace::BoxPruning( int count, const dxGeom** geoms, dArray< Pair >& pairs )
{
// Size the poslist (+1 for infinity end cap)
poslist.setSize( count );
// 1) Build main list using the primary axis
// NOTE: uses floats instead of dReals because that's what radix sort wants
for( int i = 0; i < count; ++i )
poslist[ i ] = (float)TmpGeomList[i]->aabb[ ax0idx ];
// 2) Sort the list
const uint32* Sorted = sortContext.RadixSort( poslist.data(), count );
// 3) Prune the list
const uint32* const LastSorted = Sorted + count;
const uint32* RunningAddress = Sorted;
bool bExitLoop;
Pair IndexPair;
while ( Sorted < LastSorted )
{
IndexPair.id0 = *Sorted++;
// empty, this loop just advances RunningAddress
for (bExitLoop = false; poslist[*RunningAddress++] < poslist[IndexPair.id0]; )
{
if (RunningAddress == LastSorted)
{
bExitLoop = true;
break;
}
}
if ( bExitLoop || RunningAddress == LastSorted) // Not a bug!!!
{
break;
}
const float idx0ax0max = (float)geoms[IndexPair.id0]->aabb[ax0idx+1]; // To avoid wrong decisions caused by rounding errors, cast the AABB element to float similarly as we did at the function beginning
const dReal idx0ax1max = geoms[IndexPair.id0]->aabb[ax1idx+1];
const dReal idx0ax2max = geoms[IndexPair.id0]->aabb[ax2idx+1];
for (const uint32* RunningAddress2 = RunningAddress; poslist[ IndexPair.id1 = *RunningAddress2++ ] <= idx0ax0max; )
{
const dReal* aabb0 = geoms[ IndexPair.id0 ]->aabb;
const dReal* aabb1 = geoms[ IndexPair.id1 ]->aabb;
// Intersection?
if ( idx0ax1max >= aabb1[ax1idx] && aabb1[ax1idx+1] >= aabb0[ax1idx]
&& idx0ax2max >= aabb1[ax2idx] && aabb1[ax2idx+1] >= aabb0[ax2idx] )
{
pairs.push( IndexPair );
}
if (RunningAddress2 == LastSorted)
{
break;
}
}
} // while ( RunningAddress < LastSorted && Sorted < LastSorted )
}
//==============================================================================
//------------------------------------------------------------------------------
// Radix Sort
//------------------------------------------------------------------------------
#define CHECK_PASS_VALIDITY(pass) \
/* Shortcut to current counters */ \
const uint32* CurCount = &mHistogram[pass<<8]; \
\
/* Reset flag. The sorting pass is supposed to be performed. (default) */ \
bool PerformPass = true; \
\
/* Check pass validity */ \
\
/* If all values have the same byte, sorting is useless. */ \
/* It may happen when sorting bytes or words instead of dwords. */ \
/* This routine actually sorts words faster than dwords, and bytes */ \
/* faster than words. Standard running time (O(4*n))is reduced to O(2*n) */ \
/* for words and O(n) for bytes. Running time for floats depends on actual values... */ \
\
/* Get first byte */ \
uint8 UniqueVal = *(((const uint8*)input)+pass); \
\
/* Check that byte's counter */ \
if(CurCount[UniqueVal]==nb) PerformPass=false;
// WARNING ONLY SORTS IEEE FLOATING-POINT VALUES
const uint32* RaixSortContext::RadixSort( const float* input2, uint32 nb )
{
union _type_cast_union
{
_type_cast_union(const float *floats): asFloats(floats) {}
_type_cast_union(const uint32 *uints32): asUInts32(uints32) {}
const float *asFloats;
const uint32 *asUInts32;
const uint8 *asUInts8;
};
const uint32* input = _type_cast_union(input2).asUInts32;
// Resize lists if needed
ReallocateRanksIfNecessary(nb);
// Allocate histograms & offsets on the stack
uint32 mHistogram[256*4];
uint32* mLink[256];
// Create histograms (counters). Counters for all passes are created in one run.
// Pros: read input buffer once instead of four times
// Cons: mHistogram is 4Kb instead of 1Kb
// Floating-point values are always supposed to be signed values, so there's only one code path there.
// Please note the floating point comparison needed for temporal coherence! Although the resulting asm code
// is dreadful, this is surprisingly not such a performance hit - well, I suppose that's a big one on first
// generation Pentiums....We can't make comparison on integer representations because, as Chris said, it just
// wouldn't work with mixed positive/negative values....
{
/* Clear counters/histograms */
memset(mHistogram, 0, 256*4*sizeof(uint32));
/* Prepare to count */
const uint8* p = _type_cast_union(input).asUInts8;
const uint8* pe = &p[nb*4];
uint32* h0= &mHistogram[0]; /* Histogram for first pass (LSB) */
uint32* h1= &mHistogram[256]; /* Histogram for second pass */
uint32* h2= &mHistogram[512]; /* Histogram for third pass */
uint32* h3= &mHistogram[768]; /* Histogram for last pass (MSB) */
bool AlreadySorted = true; /* Optimism... */
if (!AreRanksValid())
{
/* Prepare for temporal coherence */
const float* Running = input2;
float PrevVal = *Running;
while(p!=pe)
{
/* Read input input2 in previous sorted order */
float Val = *Running++;
/* Check whether already sorted or not */
if(Val<PrevVal) { AlreadySorted = false; break; } /* Early out */
/* Update for next iteration */
PrevVal = Val;
/* Create histograms */
h0[*p++]++; h1[*p++]++; h2[*p++]++; h3[*p++]++;
}
/* If all input values are already sorted, we just have to return and leave the */
/* previous list unchanged. That way the routine may take advantage of temporal */
/* coherence, for example when used to sort transparent faces. */
if(AlreadySorted)
{
uint32* const Ranks1 = GetRanks1();
for(uint32 i=0;i<nb;i++) Ranks1[i] = i;
return Ranks1;
}
}
else
{
/* Prepare for temporal coherence */
uint32* const Ranks1 = GetRanks1();
uint32* Indices = Ranks1;
float PrevVal = input2[*Indices];
while(p!=pe)
{
/* Read input input2 in previous sorted order */
float Val = input2[*Indices++];
/* Check whether already sorted or not */
if(Val<PrevVal) { AlreadySorted = false; break; } /* Early out */
/* Update for next iteration */
PrevVal = Val;
/* Create histograms */
h0[*p++]++; h1[*p++]++; h2[*p++]++; h3[*p++]++;
}
/* If all input values are already sorted, we just have to return and leave the */
/* previous list unchanged. That way the routine may take advantage of temporal */
/* coherence, for example when used to sort transparent faces. */
if(AlreadySorted) { return Ranks1; }
}
/* Else there has been an early out and we must finish computing the histograms */
while(p!=pe)
{
/* Create histograms without the previous overhead */
h0[*p++]++; h1[*p++]++; h2[*p++]++; h3[*p++]++;
}
}
// Compute #negative values involved if needed
uint32 NbNegativeValues = 0;
// An efficient way to compute the number of negatives values we'll have to deal with is simply to sum the 128
// last values of the last histogram. Last histogram because that's the one for the Most Significant Byte,
// responsible for the sign. 128 last values because the 128 first ones are related to positive numbers.
uint32* h3= &mHistogram[768];
for(uint32 i=128;i<256;i++) NbNegativeValues += h3[i]; // 768 for last histogram, 128 for negative part
// Radix sort, j is the pass number (0=LSB, 3=MSB)
for(uint32 j=0;j<4;j++)
{
// Should we care about negative values?
if(j!=3)
{
// Here we deal with positive values only
CHECK_PASS_VALIDITY(j);
if(PerformPass)
{
uint32* const Ranks2 = GetRanks2();
// Create offsets
mLink[0] = Ranks2;
for(uint32 i=1;i<256;i++) mLink[i] = mLink[i-1] + CurCount[i-1];
// Perform Radix Sort
const uint8* InputBytes = _type_cast_union(input).asUInts8;
InputBytes += j;
if (!AreRanksValid())
{
for(uint32 i=0;i<nb;i++)
{
*mLink[InputBytes[i<<2]]++ = i;
}
ValidateRanks();
}
else
{
uint32* const Ranks1 = GetRanks1();
uint32* Indices = Ranks1;
uint32* const IndicesEnd = Ranks1 + nb;
while(Indices!=IndicesEnd)
{
uint32 id = *Indices++;
*mLink[InputBytes[id<<2]]++ = id;
}
}
// Swap pointers for next pass. Valid indices - the most recent ones - are in mRanks after the swap.
SwapRanks();
}
}
else
{
// This is a special case to correctly handle negative values
CHECK_PASS_VALIDITY(j);
if(PerformPass)
{
uint32* const Ranks2 = GetRanks2();
// Create biased offsets, in order for negative numbers to be sorted as well
mLink[0] = Ranks2 + NbNegativeValues; // First positive number takes place after the negative ones
for(uint32 i=1;i<128;i++) mLink[i] = mLink[i-1] + CurCount[i-1]; // 1 to 128 for positive numbers
// We must reverse the sorting order for negative numbers!
mLink[255] = Ranks2;
for(uint32 i=0;i<127;i++) mLink[254-i] = mLink[255-i] + CurCount[255-i]; // Fixing the wrong order for negative values
for(uint32 i=128;i<256;i++) mLink[i] += CurCount[i]; // Fixing the wrong place for negative values
// Perform Radix Sort
if (!AreRanksValid())
{
for(uint32 i=0;i<nb;i++)
{
uint32 Radix = input[i]>>24; // Radix byte, same as above. AND is useless here (uint32).
// ### cmp to be killed. Not good. Later.
if(Radix<128) *mLink[Radix]++ = i; // Number is positive, same as above
else *(--mLink[Radix]) = i; // Number is negative, flip the sorting order
}
ValidateRanks();
}
else
{
uint32* const Ranks1 = GetRanks1();
for(uint32 i=0;i<nb;i++)
{
uint32 Radix = input[Ranks1[i]]>>24; // Radix byte, same as above. AND is useless here (uint32).
// ### cmp to be killed. Not good. Later.
if(Radix<128) *mLink[Radix]++ = Ranks1[i]; // Number is positive, same as above
else *(--mLink[Radix]) = Ranks1[i]; // Number is negative, flip the sorting order
}
}
// Swap pointers for next pass. Valid indices - the most recent ones - are in mRanks after the swap.
SwapRanks();
}
else
{
// The pass is useless, yet we still have to reverse the order of current list if all values are negative.
if(UniqueVal>=128)
{
if (!AreRanksValid())
{
uint32* const Ranks2 = GetRanks2();
// ###Possible?
for(uint32 i=0;i<nb;i++)
{
Ranks2[i] = nb-i-1;
}
ValidateRanks();
}
else
{
uint32* const Ranks1 = GetRanks1();
uint32* const Ranks2 = GetRanks2();
for(uint32 i=0;i<nb;i++) Ranks2[i] = Ranks1[nb-i-1];
}
// Swap pointers for next pass. Valid indices - the most recent ones - are in mRanks after the swap.
SwapRanks();
}
}
}
}
// Return indices
uint32* const Ranks1 = GetRanks1();
return Ranks1;
}
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