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Refactor|World|Map: Extracted algorithm for map element path intercep…
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…tion

Map now provides all the API mechanisms to implement this algorithm
outside of the map itself. In the future this can be wrapped up into
class similar to LineOfSight.
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@danij-deng
danij-deng committed Oct 11, 2013
1 parent ece0b61 commit 104d96c
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Showing 7 changed files with 212 additions and 174 deletions.
8 changes: 4 additions & 4 deletions doomsday/api/api_map.h
View file
Expand Up @@ -95,15 +95,15 @@ struct intercept_s;
///@}

/**
* @defgroup lineBoxIteratorFlags Line Box Iterator Flags
* @defgroup lineIteratorFlags Line Iterator Flags
* @ingroup apiFlags world
*/
///@{
#define LBF_SECTOR 0x1 ///< Process map lines defining sectors
#define LBF_POLYOBJ 0x2 ///< Process map lines defining polyobjs
#define LIF_SECTOR 0x1 ///< Process map lines defining sectors
#define LIF_POLYOBJ 0x2 ///< Process map lines defining polyobjs

/// Process all map line types.
#define LBF_ALL LBF_SECTOR | LBF_POLYOBJ
#define LIF_ALL LIF_SECTOR | LIF_POLYOBJ
///@}

/**
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46 changes: 24 additions & 22 deletions doomsday/client/include/world/map.h
View file
Expand Up @@ -451,7 +451,10 @@ class Map
Polyobj **poly, Plane **plane, Surface **surface) const;

int mobjBoxIterator(AABoxd const &box,
int (*callback) (struct mobj_s *, void *), void *context = 0) const;
int (*callback) (struct mobj_s *mobj, void *context), void *context = 0) const;

int mobjPathIterator(Vector2d const &from, Vector2d const &to,
int (*callback) (struct mobj_s *mobj, void *context), void *context = 0) const;

/**
* Lines and Polyobj lines (note polyobj lines are iterated first).
Expand All @@ -461,24 +464,30 @@ class Map
* equal to this will be skipped over (can be used to avoid processing
* a line multiple times during complex / non-linear traversals.
*
* @param flags @ref lineBoxIteratorFlags
* @param flags @ref lineIteratorFlags
*/
int lineBoxIterator(AABoxd const &box, int flags,
int (*callback) (Line *, void *), void *context = 0) const;
int (*callback) (Line *line, void *context), void *context = 0) const;

/// @copydoc lineBoxIterator()
inline int lineBoxIterator(AABoxd const &box,
int (*callback) (Line *, void *), void *context = 0) const
int (*callback) (Line *line, void *context), void *context = 0) const
{
return lineBoxIterator(box, LBF_ALL, callback, context);
return lineBoxIterator(box, LIF_ALL, callback, context);
}

/**
* @param flags @ref lineIteratorFlags
*/
int linePathIterator(Vector2d const &from, Vector2d const &to, int flags,
int (*callback) (Line *line, void *context), void *context = 0) const;

int bspLeafBoxIterator(AABoxd const &box, Sector *sector,
int (*callback) (BspLeaf *, void *), void *context = 0) const;
int (*callback) (BspLeaf *bspLeaf, void *context), void *context = 0) const;

/// @copydoc bspLeafsBoxIterator()
inline int bspLeafBoxIterator(AABoxd const &box,
int (*callback) (BspLeaf *, void *), void *context = 0) const
int (*callback) (BspLeaf *bspLeaf, void *context), void *context = 0) const
{
return bspLeafBoxIterator(box, 0, callback, context);
}
Expand All @@ -490,7 +499,8 @@ class Map
* multiple times during complex / non-linear traversals.
*/
int polyobjBoxIterator(AABoxd const &box,
int (*callback) (struct polyobj_s *, void *), void *context = 0) const;
int (*callback) (struct polyobj_s *polyobj, void *context),
void *context = 0) const;

/**
* The callback function will be called once for each line that crosses
Expand All @@ -506,10 +516,10 @@ class Map
* above or under the sector.
*/
int mobjTouchedSectorIterator(struct mobj_s *mo,
int (*callback) (Sector *, void *), void *context = 0) const;
int (*callback) (Sector *sector, void *context), void *context = 0) const;

int lineTouchingMobjIterator(Line *line,
int (*callback) (struct mobj_s *, void *), void *context = 0) const;
int (*callback) (struct mobj_s *mobj, void *context), void *context = 0) const;

/**
* Increment validCount before using this. 'func' is called for each mobj
Expand All @@ -520,29 +530,21 @@ class Map
* a bunch of LineMobjs iterations.)
*/
int sectorTouchingMobjIterator(Sector *sector,
int (*callback) (struct mobj_s *, void *), void *context = 0) const;

/**
* Trace a line between @a from and @a to, making a callback for each
* interceptable object linked within Blockmap cells which cover the path
* this defines.
*/
int pathTraverse(de::Vector2d const &from, de::Vector2d const &to, int flags,
traverser_t callback, void *context = 0);
int (*callback) (struct mobj_s *mobj, void *context), void *context = 0) const;

/**
* Retrieve an immutable copy of the LOS trace line state.
*
* @todo Map should not own this data.
*/
divline_t const &traceLine() const;
divline_t &traceLine() const;

/**
* Retrieve an immutable copy of the LOS TraceOpening state.
*
* @todo Map should not own this data.
*/
TraceOpening const &traceOpening() const;
TraceOpening &traceOpening() const;

/**
* Update the TraceOpening state for according to the opening defined by the
Expand Down Expand Up @@ -675,7 +677,7 @@ class Map
*
* @note This result is not cached. May return @c 0 if no bias sources exist.
*/
BiasSource *biasSourceNear(de::Vector3d const &point) const;
BiasSource *biasSourceNear(Vector3d const &point) const;

/**
* Lookup the unique index for the given bias @a source.
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131 changes: 125 additions & 6 deletions doomsday/client/src/world/api_map.cpp
View file
Expand Up @@ -45,6 +45,7 @@

#ifdef __CLIENT__
# include "render/lightgrid.h"
# include "render/r_main.h" // validCount
#endif

using namespace de;
Expand Down Expand Up @@ -1624,38 +1625,156 @@ DENG_EXTERN_C int BspLeaf_BoxIterator(AABoxd const *box, Sector *sector,
return App_World().map().bspLeafBoxIterator(*box, sector, callback, context);
}

static void collectLineIntercept(Line &line, divline_t const &traceLos)
{
fixed_t lineFromX[2] = { DBL2FIX(line.fromOrigin().x), DBL2FIX(line.fromOrigin().y) };
fixed_t lineToX[2] = { DBL2FIX( line.toOrigin().x), DBL2FIX( line.toOrigin().y) };

// Is this line crossed?
// Avoid precision problems with two routines.
int s1, s2;
if(traceLos.direction[VX] > FRACUNIT * 16 || traceLos.direction[VY] > FRACUNIT * 16 ||
traceLos.direction[VX] < -FRACUNIT * 16 || traceLos.direction[VY] < -FRACUNIT * 16)
{
s1 = V2x_PointOnLineSide(lineFromX, traceLos.origin, traceLos.direction);
s2 = V2x_PointOnLineSide(lineToX, traceLos.origin, traceLos.direction);
}
else
{
s1 = line.pointOnSide(Vector2d(FIX2FLT(traceLos.origin[VX]),
FIX2FLT(traceLos.origin[VY]))) < 0;
s2 = line.pointOnSide(Vector2d(FIX2FLT(traceLos.origin[VX] + traceLos.direction[VX]),
FIX2FLT(traceLos.origin[VY] + traceLos.direction[VY]))) < 0;
}
if(s1 == s2) return;

fixed_t lineDirectionX[2] = { DBL2FIX(line.direction().x), DBL2FIX(line.direction().y) };

// On the correct side of the trace origin?
float distance = FIX2FLT(V2x_Intersection(lineFromX, lineDirectionX,
traceLos.origin, traceLos.direction));
if(distance >= 0)
{
P_AddIntercept(ICPT_LINE, distance, &line);
}
}

static int collectCellLineInterceptsWorker(Line *line, void *context)
{
collectLineIntercept(*line, *static_cast<divline_t *>(context));
return false; // Continue iteration.
}

static void collectMobjIntercept(mobj_t &mobj, divline_t const &traceLos)
{
// Ignore cameras.
if(mobj.dPlayer && (mobj.dPlayer->flags & DDPF_CAMERA))
return;

// Check a corner to corner crossection for hit.
AABoxd const aaBox = Mobj_AABox(mobj);

vec2d_t from, to;
if((traceLos.direction[VX] ^ traceLos.direction[VY]) > 0)
{
// \ Slope
V2d_Set(from, aaBox.minX, aaBox.maxY);
V2d_Set(to, aaBox.maxX, aaBox.minY);
}
else
{
// / Slope
V2d_Set(from, aaBox.minX, aaBox.minY);
V2d_Set(to, aaBox.maxX, aaBox.maxY);
}

// Is this line crossed?
if(Divline_PointOnSide(&traceLos, from) == Divline_PointOnSide(&traceLos, to))
return;

// Calculate interception point.
divline_t dl;
dl.origin[VX] = DBL2FIX(from[VX]);
dl.origin[VY] = DBL2FIX(from[VY]);
dl.direction[VX] = DBL2FIX(to[VX] - from[VX]);
dl.direction[VY] = DBL2FIX(to[VY] - from[VY]);
coord_t distance = FIX2FLT(Divline_Intersection(&dl, &traceLos));

// On the correct side of the trace origin?
if(distance >= 0)
{
P_AddIntercept(ICPT_MOBJ, distance, &mobj);
}
}

static int collectCellMobjInterceptsWorker(mobj_t *mobj, void *context)
{
collectMobjIntercept(*mobj, *static_cast<divline_t *>(context));
return false; // Continue iteration.
}

static int traverseMapPath(Map &map, Vector2d const &from, Vector2d const &to,
int flags, traverser_t callback, void *context = 0)
{
// A new trace begins.
divline_t &traceLine = map.traceLine();

traceLine.origin[VX] = FLT2FIX(from.x);
traceLine.origin[VY] = FLT2FIX(from.y);
traceLine.direction[VX] = FLT2FIX(to.x - from.x);
traceLine.direction[VY] = FLT2FIX(to.y - from.y);

P_ClearIntercepts();
validCount++;

// Step #1: Collect intercepts.
if(flags & PT_ADDLINES)
{
map.linePathIterator(from, to, LIF_ALL, collectCellLineInterceptsWorker, &traceLine);
}
if(flags & PT_ADDMOBJS)
{
map.mobjPathIterator(from, to, collectCellMobjInterceptsWorker, &traceLine);
}

// Step #2: Process sorted intercepts.
return P_TraverseIntercepts(callback, context);
}

#undef P_PathTraverse2
DENG_EXTERN_C int P_PathTraverse2(const_pvec2d_t from, const_pvec2d_t to,
int flags, traverser_t callback, void *context)
{
if(!App_World().hasMap()) return false; // Continue iteration.
return App_World().map().pathTraverse(from, to, flags, callback, context);
return traverseMapPath(App_World().map(), from, to, flags, callback, context);
}

#undef P_PathTraverse
DENG_EXTERN_C int P_PathTraverse(const_pvec2d_t from, const_pvec2d_t to,
int flags, traverser_t callback)
{
if(!App_World().hasMap()) return false; // Continue iteration.
return App_World().map().pathTraverse(from, to, flags, callback);
return traverseMapPath(App_World().map(), from, to, flags, callback);
}

#undef P_PathXYTraverse2
DENG_EXTERN_C int P_PathXYTraverse2(coord_t fromX, coord_t fromY,
coord_t toX, coord_t toY, int flags, traverser_t callback, void *context)
{
if(!App_World().hasMap()) return false; // Continue iteration.
return App_World().map().pathTraverse(Vector2d(fromX, fromY), Vector2d(toX, toY),
flags, callback, context);
return traverseMapPath(App_World().map(),
Vector2d(fromX, fromY), Vector2d(toX, toY),
flags, callback, context);
}

#undef P_PathXYTraverse
DENG_EXTERN_C int P_PathXYTraverse(coord_t fromX, coord_t fromY, coord_t toX, coord_t toY, int flags,
traverser_t callback)
{
if(!App_World().hasMap()) return false; // Continue iteration.
return App_World().map().pathTraverse(Vector2d(fromX, fromY), Vector2d(toX, toY),
flags, callback);
return traverseMapPath(App_World().map(),
Vector2d(fromX, fromY), Vector2d(toX, toY),
flags, callback);
}

#undef P_CheckLineSight
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