mirrors
/
OpenTTD
mirror of https://github.com/OpenTTD/OpenTTD.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

(svn r26309) -Codechange: instead of memsetting a byte array with zero, use a set for marking the flow area of a river

This commit is contained in:
rubidium 2014-02-06 20:51:01 +00:00
parent 30a95966ec
commit f99d380583
1 changed files with 16 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

30
src/landscape.cpp
View File

@ -32,6 +32,7 @@
#include "company_func.h"
#include "pathfinder/npf/aystar.h"
#include <list>
#include <set>
#include "table/strings.h"
#include "table/sprites.h"
@ -1095,18 +1096,20 @@ static void BuildRiver(TileIndex begin, TileIndex end)
/**
* Try to flow the river down from a given begin.
* @param marks Array for temporary of iterated tiles.
* @param spring The springing point of the river.
* @param begin The begin point we are looking from; somewhere down hill from the spring.
* @return True iff a river could/has been built, otherwise false.
*/
static bool FlowRiver(bool *marks, TileIndex spring, TileIndex begin)
static bool FlowRiver(TileIndex spring, TileIndex begin)
{
#define SET_MARK(x) marks.insert(x)
#define IS_MARKED(x) (marks.find(x) != marks.end())
uint height = TileHeight(begin);
if (IsWaterTile(begin)) return DistanceManhattan(spring, begin) > _settings_game.game_creation.min_river_length;
MemSetT(marks, 0, MapSize());
marks[begin] = true;
std::set<TileIndex> marks;
SET_MARK(begin);
/* Breadth first search for the closest tile we can flow down to. */
std::list<TileIndex> queue;
@ -1127,8 +1130,8 @@ static bool FlowRiver(bool *marks, TileIndex spring, TileIndex begin)
for (DiagDirection d = DIAGDIR_BEGIN; d < DIAGDIR_END; d++) {
TileIndex t2 = end + TileOffsByDiagDir(d);
if (IsValidTile(t2) && !marks[t2] && FlowsDown(end, t2)) {
marks[t2] = true;
if (IsValidTile(t2) && !IS_MARKED(t2) && FlowsDown(end, t2)) {
SET_MARK(t2);
count++;
queue.push_back(t2);
}
@ -1137,13 +1140,14 @@ static bool FlowRiver(bool *marks, TileIndex spring, TileIndex begin)
if (found) {
/* Flow further down hill. */
found = FlowRiver(marks, spring, end);
found = FlowRiver(spring, end);
} else if (count > 32) {
/* Maybe we can make a lake. Find the Nth of the considered tiles. */
TileIndex lakeCenter = 0;
for (int i = RandomRange(count - 1); i != 0; lakeCenter++) {
if (marks[lakeCenter]) i--;
}
int i = RandomRange(count - 1) + 1;
std::set<TileIndex>::const_iterator cit = marks.begin();
while (--i) cit++;
lakeCenter = *cit;
if (IsValidTile(lakeCenter) &&
/* A river, or lake, can only be built on flat slopes. */
@ -1167,6 +1171,7 @@ static bool FlowRiver(bool *marks, TileIndex spring, TileIndex begin)
}
}
marks.clear();
if (found) BuildRiver(begin, end);
return found;
}
@ -1181,19 +1186,16 @@ static void CreateRivers()
uint wells = ScaleByMapSize(4 << _settings_game.game_creation.amount_of_rivers);
SetGeneratingWorldProgress(GWP_RIVER, wells + 256 / 64); // Include the tile loop calls below.
bool *marks = CallocT<bool>(MapSize());
for (; wells != 0; wells--) {
IncreaseGeneratingWorldProgress(GWP_RIVER);
for (int tries = 0; tries < 128; tries++) {
TileIndex t = RandomTile();
if (!CircularTileSearch(&t, 8, FindSpring, NULL)) continue;
if (FlowRiver(marks, t, t)) break;
if (FlowRiver(t, t)) break;
}
}
free(marks);
/* Run tile loop to update the ground density. */
for (uint i = 0; i != 256; i++) {
if (i % 64 == 0) IncreaseGeneratingWorldProgress(GWP_RIVER);