scummvm/engines/saga/actor_path.cpp
D G Turner c825cc41a5 SAGA: Workaround fix for IHNM pathfinding glitches.
This fixes bug #3360396 - "IHNM: Can't use right monitor with ellen".
Have done a full playtest of IHNM to ensure this fixes the issue
without any other regressions.
Thanks to eriktorbjorn for creating this patch.
2012-06-17 02:10:04 +01:00

662 lines
16 KiB
C++

/* ScummVM - Graphic Adventure Engine
*
* ScummVM is the legal property of its developers, whose names
* are too numerous to list here. Please refer to the COPYRIGHT
* file distributed with this source distribution.
*
* 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 Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
#include "saga/saga.h"
#include "saga/actor.h"
#include "saga/objectmap.h"
#include "saga/scene.h"
namespace Saga {
static const PathDirectionData pathDirectionLUT[8][3] = {
{ { 0, 0, -1 }, { 7, -1, -1 }, { 4, 1, -1 } },
{ { 1, 1, 0 }, { 4, 1, -1 }, { 5, 1, 1 } },
{ { 2, 0, 1 }, { 5, 1, 1 }, { 6, -1, 1 } },
{ { 3, -1, 0 }, { 6, -1, 1 }, { 7, -1, -1 } },
{ { 0, 0, -1 }, { 1, 1, 0 }, { 4, 1, -1 } },
{ { 1, 1, 0 }, { 2, 0, 1 }, { 5, 1, 1 } },
{ { 2, 0, 1 }, { 3, -1, 0 }, { 6, -1, 1 } },
{ { 3, -1, 0 }, { 0, 0, -1 }, { 7, -1, -1 } }
};
static const int pathDirectionLUT2[8][2] = {
{ 0, -1 },
{ 1, 0 },
{ 0, 1 },
{ -1, 0 },
{ 1, -1 },
{ 1, 1 },
{ -1, 1 },
{ -1, -1 }
};
inline int16 int16Compare(int16 i1, int16 i2) {
return ((i1) > (i2) ? 1 : ((i1) < (i2) ? -1 : 0));
}
inline int16 quickDistance(const Point &point1, const Point &point2, int16 compressX) {
Point delta;
delta.x = ABS(point1.x - point2.x) / compressX;
delta.y = ABS(point1.y - point2.y);
return ((delta.x < delta.y) ? (delta.y + delta.x / 2) : (delta.x + delta.y / 2));
}
inline void calcDeltaS(const Point &point1, const Point &point2, Point &delta, Point &s) {
delta.x = point2.x - point1.x;
if (delta.x == 0) {
s.x = 0;
} else {
if (delta.x > 0) {
s.x = 1;
} else {
s.x = -1;
delta.x = -delta.x;
}
}
delta.y = point2.y - point1.y;
if (delta.y == 0) {
s.y = 0;
} else {
if (delta.y > 0) {
s.y = 1;
} else {
s.y = -1;
delta.y = -delta.y;
}
}
}
void Actor::findActorPath(ActorData *actor, const Point &fromPoint, const Point &toPoint) {
Point iteratorPoint;
Point bestPoint;
int maskType;
int i;
Rect intersect;
#ifdef ACTOR_DEBUG
_debugPointsCount = 0;
#endif
// WORKAROUND for bug #3360396. Path finding in IHNM is a bit buggy
// compared to the original, which occasionally leads to the player
// leaving the room instead of interacting with an object. So far, no
// one has figured out how to fix this properly. As a temporary [*]
// solution, we try to fix this on a case-by-case basis.
//
// The workaround is to assume that the player wants to stay in the
// room, unless he or she explicitly clicked on an exit zone.
//
// [*] And there is nothing more permanent than a temporary solution...
bool pathFindingWorkaround = false;
if (_vm->getGameId() == GID_IHNM) {
int chapter = _vm->_scene->currentChapterNumber();
int scene = _vm->_scene->currentSceneNumber();
// Ellen, in the room with the monitors.
if (chapter == 3 && scene == 54)
pathFindingWorkaround = true;
// Nimdok in the recovery room
if (chapter == 4 && scene == 71)
pathFindingWorkaround = true;
}
int hitZoneIndex;
const HitZone *hitZone;
bool restrictToRoom = false;
if (pathFindingWorkaround) {
restrictToRoom = true;
hitZoneIndex = _vm->_scene->_actionMap->hitTest(toPoint);
if (hitZoneIndex != -1) {
hitZone = _vm->_scene->_actionMap->getHitZone(hitZoneIndex);
if (hitZone->getFlags() & kHitZoneExit) {
restrictToRoom = false;
}
}
}
actor->_walkStepsCount = 0;
if (fromPoint == toPoint) {
actor->addWalkStepPoint(toPoint);
return;
}
for (iteratorPoint.y = 0; iteratorPoint.y < _yCellCount; iteratorPoint.y++) {
for (iteratorPoint.x = 0; iteratorPoint.x < _xCellCount; iteratorPoint.x++) {
if (_vm->_scene->validBGMaskPoint(iteratorPoint)) {
maskType = _vm->_scene->getBGMaskType(iteratorPoint);
setPathCell(iteratorPoint, _vm->_scene->getDoorState(maskType) ? kPathCellBarrier : kPathCellEmpty);
if (restrictToRoom) {
hitZoneIndex = _vm->_scene->_actionMap->hitTest(iteratorPoint);
if (hitZoneIndex != -1) {
hitZone = _vm->_scene->_actionMap->getHitZone(hitZoneIndex);
if (hitZone->getFlags() & kHitZoneExit) {
setPathCell(iteratorPoint, kPathCellBarrier);
}
}
}
} else {
setPathCell(iteratorPoint, kPathCellBarrier);
}
}
}
for (i = 0; i < _barrierCount; i++) {
intersect.left = MAX(_pathRect.left, _barrierList[i].left);
intersect.top = MAX(_pathRect.top, _barrierList[i].top);
intersect.right = MIN(_pathRect.right, _barrierList[i].right);
intersect.bottom = MIN(_pathRect.bottom, _barrierList[i].bottom);
for (iteratorPoint.y = intersect.top; iteratorPoint.y < intersect.bottom; iteratorPoint.y++) {
for (iteratorPoint.x = intersect.left; iteratorPoint.x < intersect.right; iteratorPoint.x++) {
setPathCell(iteratorPoint, kPathCellBarrier);
}
}
}
#ifdef ACTOR_DEBUG
for (iteratorPoint.y = 0; iteratorPoint.y < _yCellCount; iteratorPoint.y++) {
for (iteratorPoint.x = 0; iteratorPoint.x < _xCellCount; iteratorPoint.x++) {
if (getPathCell(iteratorPoint) == kPathCellBarrier) {
addDebugPoint(iteratorPoint, 24);
}
}
}
#endif
if (scanPathLine(fromPoint, toPoint)) {
actor->addWalkStepPoint(fromPoint);
actor->addWalkStepPoint(toPoint);
return;
}
i = fillPathArray(fromPoint, toPoint, bestPoint);
if (fromPoint == bestPoint) {
actor->addWalkStepPoint(bestPoint);
return;
}
if (i == 0) {
error("fillPathArray returns zero");
}
setActorPath(actor, fromPoint, bestPoint);
}
bool Actor::scanPathLine(const Point &point1, const Point &point2) {
Point point;
Point delta;
Point s;
Point fDelta;
int16 errterm;
calcDeltaS(point1, point2, delta, s);
point = point1;
fDelta.x = delta.x * 2;
fDelta.y = delta.y * 2;
if (delta.y > delta.x) {
errterm = fDelta.x - delta.y;
while (delta.y > 0) {
while (errterm >= 0) {
point.x += s.x;
errterm -= fDelta.y;
}
point.y += s.y;
errterm += fDelta.x;
if (!validPathCellPoint(point)) {
return false;
}
if (getPathCell(point) == kPathCellBarrier) {
return false;
}
delta.y--;
}
} else {
errterm = fDelta.y - delta.x;
while (delta.x > 0) {
while (errterm >= 0) {
point.y += s.y;
errterm -= fDelta.x;
}
point.x += s.x;
errterm += fDelta.y;
if (!validPathCellPoint(point)) {
return false;
}
if (getPathCell(point) == kPathCellBarrier) {
return false;
}
delta.x--;
}
}
return true;
}
int Actor::fillPathArray(const Point &fromPoint, const Point &toPoint, Point &bestPoint) {
int bestRating;
int currentRating;
Point bestPath;
int pointCounter;
const PathDirectionData *samplePathDirection;
Point nextPoint;
int directionCount;
int16 compressX = (_vm->getGameId() == GID_ITE) ? 2 : 1;
Common::List<PathDirectionData> pathDirectionQueue;
pointCounter = 0;
bestRating = quickDistance(fromPoint, toPoint, compressX);
bestPath = fromPoint;
for (int8 startDirection = 0; startDirection < 4; startDirection++) {
PathDirectionData tmp = { startDirection, fromPoint.x, fromPoint.y };
pathDirectionQueue.push_back(tmp);
}
if (validPathCellPoint(fromPoint)) {
setPathCell(fromPoint, kDirUp);
#ifdef ACTOR_DEBUG
addDebugPoint(fromPoint, 24+36);
#endif
}
while (!pathDirectionQueue.empty()) {
PathDirectionData curPathDirection = pathDirectionQueue.front();
pathDirectionQueue.pop_front();
for (directionCount = 0; directionCount < 3; directionCount++) {
samplePathDirection = &pathDirectionLUT[curPathDirection.direction][directionCount];
nextPoint = Point(curPathDirection.x, curPathDirection.y);
nextPoint.x += samplePathDirection->x;
nextPoint.y += samplePathDirection->y;
if (!validPathCellPoint(nextPoint)) {
continue;
}
if (getPathCell(nextPoint) != kPathCellEmpty) {
continue;
}
setPathCell(nextPoint, samplePathDirection->direction);
#ifdef ACTOR_DEBUG
addDebugPoint(nextPoint, samplePathDirection->direction + 96);
#endif
PathDirectionData tmp = {
samplePathDirection->direction,
nextPoint.x, nextPoint.y };
pathDirectionQueue.push_back(tmp);
++pointCounter;
if (nextPoint == toPoint) {
bestPoint = toPoint;
return pointCounter;
}
currentRating = quickDistance(nextPoint, toPoint, compressX);
if (currentRating < bestRating) {
bestRating = currentRating;
bestPath = nextPoint;
}
}
}
bestPoint = bestPath;
return pointCounter;
}
void Actor::setActorPath(ActorData *actor, const Point &fromPoint, const Point &toPoint) {
Point nextPoint;
int8 direction;
_pathList[0] = toPoint;
nextPoint = toPoint;
_pathListIndex = 0;
while (!(nextPoint == fromPoint)) {
direction = getPathCell(nextPoint);
if ((direction < 0) || (direction >= 8)) {
error("Actor::setActorPath error direction 0x%X", direction);
}
nextPoint.x -= pathDirectionLUT2[direction][0];
nextPoint.y -= pathDirectionLUT2[direction][1];
++_pathListIndex;
if (_pathListIndex >= _pathList.size()) {
_pathList.push_back(nextPoint);
} else {
_pathList[_pathListIndex] = nextPoint;
}
#ifdef ACTOR_DEBUG
addDebugPoint(nextPoint, 0x8a);
#endif
}
pathToNode();
removeNodes();
nodeToPath();
removePathPoints();
for (uint i = 0; i < _pathNodeList.size(); i++) {
actor->addWalkStepPoint(_pathNodeList[i].point);
}
}
void Actor::pathToNode() {
Point point1, point2, delta;
int direction;
int i;
direction = 0;
_pathNodeList.clear();
_pathNodeList.push_back(PathNode(_pathList[_pathListIndex]));
for (i = _pathListIndex; i > 0; i--) {
point1 = _pathList[i];
point2 = _pathList[i - 1];
if (direction == 0) {
delta.x = int16Compare(point2.x, point1.x);
delta.y = int16Compare(point2.y, point1.y);
direction++;
}
if ((point1.x + delta.x != point2.x) || (point1.y + delta.y != point2.y)) {
_pathNodeList.push_back(PathNode(point1));
direction--;
i++;
}
}
_pathNodeList.push_back(PathNode(_pathList[0]));
}
uint pathLine(PointList &pointList, uint idx, const Point &point1, const Point &point2) {
Point point;
Point delta;
Point tempPoint;
Point s;
int16 errterm;
uint res;
calcDeltaS(point1, point2, delta, s);
point = point1;
tempPoint.x = delta.x * 2;
tempPoint.y = delta.y * 2;
if (delta.y > delta.x) {
errterm = tempPoint.x - delta.y;
res = delta.y;
while (delta.y > 0) {
while (errterm >= 0) {
point.x += s.x;
errterm -= tempPoint.y;
}
point.y += s.y;
errterm += tempPoint.x;
if (idx >= pointList.size()) {
pointList.push_back(point);
} else {
pointList[idx] = point;
}
++idx;
delta.y--;
}
} else {
errterm = tempPoint.y - delta.x;
res = delta.x;
while (delta.x > 0) {
while (errterm >= 0) {
point.y += s.y;
errterm -= tempPoint.x;
}
point.x += s.x;
errterm += tempPoint.y;
if (idx >= pointList.size()) {
pointList.push_back(point);
} else {
pointList[idx] = point;
}
++idx;
delta.x--;
}
}
return res;
}
void Actor::nodeToPath() {
uint i;
Point point1, point2;
for (i = 0; i < _pathList.size(); i++) {
_pathList[i].x = _pathList[i].y = PATH_NODE_EMPTY;
}
_pathListIndex = 1;
_pathList[0] = _pathNodeList[0].point;
_pathNodeList[0].link = 0;
for (i = 0; i < _pathNodeList.size() - 1; i++) {
point1 = _pathNodeList[i].point;
point2 = _pathNodeList[i + 1].point;
_pathListIndex += pathLine(_pathList, _pathListIndex, point1, point2);
_pathNodeList[i + 1].link = _pathListIndex - 1;
}
_pathListIndex--;
_pathNodeList.back().link = _pathListIndex;
}
void Actor::removeNodes() {
uint i, j, k;
// If there are only two nodes, nothing to be done
if (_pathNodeList.size() <= 2)
return;
// If there is a direct connection between the first and last node, we can
// remove all nodes in between and are done.
if (scanPathLine(_pathNodeList.front().point, _pathNodeList.back().point)) {
_pathNodeList[1] = _pathNodeList.back();
_pathNodeList.resize(2);
}
if (_pathNodeList.size() <= 4)
return;
// Scan the nodes in reverse order, and look for a node which can be
// directly reached from the first node. If we find any, skip directly
// from the first node to that node (by marking all nodes in between as
// empty).
for (i = _pathNodeList.size() - 2; i > 1; i--) {
if (_pathNodeList[i].point.x == PATH_NODE_EMPTY) {
continue;
}
if (scanPathLine(_pathNodeList.front().point, _pathNodeList[i].point)) {
for (j = 1; j < i; j++) {
_pathNodeList[j].point.x = PATH_NODE_EMPTY;
}
break;
}
}
// Now do the reverse: Find the first node which is directly connected
// to the end node; if we find any, skip over all nodes in between.
for (i = 1; i < _pathNodeList.size() - 2; i++) {
if (_pathNodeList[i].point.x == PATH_NODE_EMPTY) {
continue;
}
if (scanPathLine(_pathNodeList.back().point, _pathNodeList[i].point)) {
for (j = i + 1; j < _pathNodeList.size() - 1; j++) {
_pathNodeList[j].point.x = PATH_NODE_EMPTY;
}
break;
}
}
condenseNodeList();
// Finally, try arbitrary combinations of non-adjacent nodes and see
// if we can skip over any of them.
for (i = 1; i < _pathNodeList.size() - 2; i++) {
if (_pathNodeList[i].point.x == PATH_NODE_EMPTY) {
continue;
}
for (j = i + 2; j < _pathNodeList.size() - 1; j++) {
if (_pathNodeList[j].point.x == PATH_NODE_EMPTY) {
continue;
}
if (scanPathLine(_pathNodeList[i].point, _pathNodeList[j].point)) {
for (k = i + 1; k < j; k++) {
_pathNodeList[k].point.x = PATH_NODE_EMPTY;
}
}
}
}
condenseNodeList();
}
/** Remove all empty nodes from _pathNodeList. */
void Actor::condenseNodeList() {
uint i, j, count;
count = _pathNodeList.size();
for (i = 1; i < _pathNodeList.size() - 1; i++) {
if (_pathNodeList[i].point.x == PATH_NODE_EMPTY) {
j = i + 1;
while (_pathNodeList[j].point.x == PATH_NODE_EMPTY) {
j++;
}
_pathNodeList[i] = _pathNodeList[j];
count = i + 1;
_pathNodeList[j].point.x = PATH_NODE_EMPTY;
if (j == _pathNodeList.size() - 1) {
break;
}
}
}
_pathNodeList.resize(count);
}
void Actor::removePathPoints() {
uint i, j, l;
int start;
int end;
Point point1, point2;
if (_pathNodeList.size() <= 2)
return;
PathNodeList newPathNodeList;
// Add the first node
newPathNodeList.push_back(_pathNodeList.front());
// Process all nodes between the first and the last.
for (i = 1; i < _pathNodeList.size() - 1; i++) {
newPathNodeList.push_back(_pathNodeList[i]);
for (j = 5; j > 0; j--) {
start = _pathNodeList[i].link - j;
end = _pathNodeList[i].link + j;
if (start < 0 || end > (int)_pathListIndex) {
continue;
}
point1 = _pathList[start];
point2 = _pathList[end];
if ((point1.x == PATH_NODE_EMPTY) || (point2.x == PATH_NODE_EMPTY)) {
continue;
}
if (scanPathLine(point1, point2)) {
for (l = 1; l < newPathNodeList.size(); l++) {
if (start <= newPathNodeList[l].link) {
newPathNodeList.resize(l + 1);
newPathNodeList.back().point = point1;
newPathNodeList.back().link = start;
newPathNodeList.resize(l + 2);
break;
}
}
newPathNodeList.back().point = point2;
newPathNodeList.back().link = end;
for (int k = start + 1; k < end; k++) {
_pathList[k].x = PATH_NODE_EMPTY;
}
break;
}
}
}
// Add the last node
newPathNodeList.push_back(_pathNodeList.back());
// Copy newPathNodeList into _pathNodeList, skipping any duplicate points
_pathNodeList.clear();
for (i = 0; i < newPathNodeList.size(); i++) {
if (((newPathNodeList.size() - 1) == i) || (newPathNodeList[i].point != newPathNodeList[i + 1].point)) {
_pathNodeList.push_back(newPathNodeList[i]);
}
}
}
#ifdef ACTOR_DEBUG
void Actor::drawPathTest() {
uint i;
for (i = 0; i < _debugPointsCount; i++) {
_vm->_gfx->setPixelColor(_debugPoints[i].point.x, _debugPoints[i].point.y, _debugPoints[i].color);
}
}
#endif
} // End of namespace Saga