Changeset - r7833:774556885fd7
[Not reviewed]
master
0 10 0
truelight - 17 years ago 2007-11-04 23:06:39
truelight@openttd.org
(svn r11383) -Codechange: fixed all the mess around KillFirstBit (tnx to Rubidium and skidd13)
10 files changed with 22 insertions and 41 deletions:
0 comments (0 inline, 0 general)
src/macros.h
Show inline comments
 
@@ -354,7 +354,7 @@ template<typename T> static inline T TOG
 
 */
 
#define IS_CUSTOM_SPRITE(sprite) ((sprite) >= SPR_SIGNALS_BASE)
 

	
 
extern const byte _ffb_64[128];
 
extern const byte _ffb_64[64];
 

	
 
/**
 
 * Returns the first occure of a bit in a 6-bit value (from right).
 
@@ -369,17 +369,6 @@ extern const byte _ffb_64[128];
 
#define FIND_FIRST_BIT(x) _ffb_64[(x)]
 

	
 
/**
 
 * Returns a value with the first occured of a bit set to zero.
 
 *
 
 * Returns x with the first bit from LSB that is not zero set
 
 * to zero. So, 110100 returns 110000, 000001 returns 000000, etc.
 
 *
 
 * @param x The value to returned a new value
 
 * @return The value which the first bit is set to zero
 
 */
 
#define KILL_FIRST_BIT(x) _ffb_64[(x) + 64]
 

	
 
/**
 
 * Finds the position of the first bit in an integer.
 
 *
 
 * This function returns the position of the first bit set in the
 
@@ -416,14 +405,15 @@ Faster ( or at least cleaner ) implement
 
 * Clear the first bit in an integer.
 
 *
 
 * This function returns a value where the first bit (from LSB)
 
 * is cleared. This function checks only the bits of 0x3F3F!
 
 * is cleared.
 
 * So, 110100 returns 110000, 000001 returns 000000, etc.
 
 *
 
 * @param value The value to clear the first bit
 
 * @return The new value with the first bit cleared
 
 */
 
static inline uint KillFirstBit2x64(uint value)
 
template<typename T> static inline T KillFirstBit(T value)
 
{
 
	return value &= (uint)(value - 1) | 0x3FFFC0C0;
 
	return value &= (T)(value - 1);
 
}
 

	
 
/**
src/pathfind.cpp
Show inline comments
 
@@ -234,7 +234,7 @@ static uint SkipToEndOfTunnel(TrackPathF
 
	return flotr.tile;
 
}
 

	
 
const byte _ffb_64[128] = {
 
const byte _ffb_64[64] = {
 
 0,  0,  1,  0,  2,  0,  1,  0,
 
 3,  0,  1,  0,  2,  0,  1,  0,
 
 4,  0,  1,  0,  2,  0,  1,  0,
 
@@ -243,15 +243,6 @@ const byte _ffb_64[128] = {
 
 3,  0,  1,  0,  2,  0,  1,  0,
 
 4,  0,  1,  0,  2,  0,  1,  0,
 
 3,  0,  1,  0,  2,  0,  1,  0,
 

	
 
 0,  0,  0,  2,  0,  4,  4,  6,
 
 0,  8,  8, 10,  8, 12, 12, 14,
 
 0, 16, 16, 18, 16, 20, 20, 22,
 
16, 24, 24, 26, 24, 28, 28, 30,
 
 0, 32, 32, 34, 32, 36, 36, 38,
 
32, 40, 40, 42, 40, 44, 44, 46,
 
32, 48, 48, 50, 48, 52, 52, 54,
 
48, 56, 56, 58, 56, 60, 60, 62,
 
};
 

	
 
static void TPFMode1(TrackPathFinder* tpf, TileIndex tile, DiagDirection direction);
 
@@ -307,10 +298,10 @@ static inline void TPFMode1_NormalCase(T
 
	bits &= 0xBF;
 

	
 
	if (bits != 0) {
 
		if (!tpf->disable_tile_hash || (tpf->rd.cur_length <= 64 && (KILL_FIRST_BIT(bits) == 0 || ++tpf->rd.depth <= 7))) {
 
		if (!tpf->disable_tile_hash || (tpf->rd.cur_length <= 64 && (KillFirstBit(bits) == 0 || ++tpf->rd.depth <= 7))) {
 
			do {
 
				int i = FIND_FIRST_BIT(bits);
 
				bits = KILL_FIRST_BIT(bits);
 
				bits = KillFirstBit(bits);
 

	
 
				tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i + 8) : i);
 
				RememberData rd = tpf->rd;
 
@@ -391,7 +382,7 @@ static void TPFMode1(TrackPathFinder* tp
 

	
 
	do {
 
		uint i = FIND_FIRST_BIT(bits);
 
		bits = KILL_FIRST_BIT(bits);
 
		bits = KillFirstBit(bits);
 

	
 
		tpf->the_dir = (Trackdir)((_otherdir_mask[direction] & (byte)(1 << i)) ? (i + 8) : i);
 
		RememberData rd = tpf->rd;
 
@@ -803,7 +794,7 @@ start_at:
 
				bits = TrackdirBitsToTrackBits((TrackdirBits)(ts & TRACKDIR_BIT_MASK));
 

	
 
				/* Check that the tile contains exactly one track */
 
				if (bits == 0 || KILL_FIRST_BIT(bits) != 0) break;
 
				if (bits == 0 || KillFirstBit(bits) != 0) break;
 

	
 
				if (!HASBIT(tpf->railtypes, GetRailType(tile))) {
 
					bits = TRACK_BIT_NONE;
src/rail.h
Show inline comments
 
@@ -370,7 +370,7 @@ static inline Track FindFirstTrack(Track
 
 */
 
static inline Track TrackBitsToTrack(TrackBits tracks)
 
{
 
	assert(tracks == INVALID_TRACK_BIT || (tracks != TRACK_BIT_NONE && KILL_FIRST_BIT(tracks & TRACK_BIT_MASK) == 0));
 
	assert(tracks == INVALID_TRACK_BIT || (tracks != TRACK_BIT_NONE && KillFirstBit(tracks & TRACK_BIT_MASK) == TRACK_BIT_NONE));
 
	return tracks != INVALID_TRACK_BIT ? (Track)FIND_FIRST_BIT(tracks & TRACK_BIT_MASK) : INVALID_TRACK;
 
}
 

	
 
@@ -785,7 +785,7 @@ static inline bool HasPowerOnRail(RailTy
 
static inline bool TracksOverlap(TrackBits bits)
 
{
 
	/* With no, or only one track, there is no overlap */
 
	if (bits == 0 || KILL_FIRST_BIT(bits) == 0) return false;
 
	if (bits == TRACK_BIT_NONE || KillFirstBit(bits) == TRACK_BIT_NONE) return false;
 
	/* We know that there are at least two tracks present. When there are more
 
	 * than 2 tracks, they will surely overlap. When there are two, they will
 
	 * always overlap unless they are lower & upper or right & left. */
src/rail_cmd.cpp
Show inline comments
 
@@ -802,7 +802,7 @@ CommandCost CmdBuildSingleSignal(TileInd
 
	{
 
		/* See if this is a valid track combination for signals, (ie, no overlap) */
 
		TrackBits trackbits = GetTrackBits(tile);
 
		if (KILL_FIRST_BIT(trackbits) != 0 && /* More than one track present */
 
		if (KillFirstBit(trackbits) != TRACK_BIT_NONE && /* More than one track present */
 
				trackbits != TRACK_BIT_HORZ &&
 
				trackbits != TRACK_BIT_VERT) {
 
			return CMD_ERROR;
src/roadveh_cmd.cpp
Show inline comments
 
@@ -1211,7 +1211,7 @@ static Trackdir RoadFindPathToDest(Vehic
 
	}
 

	
 
	/* Only one track to choose between? */
 
	if (!(KillFirstBit2x64(trackdirs))) {
 
	if (KillFirstBit(trackdirs) != TRACKDIR_BIT_NONE) {
 
		return_track(FindFirstBit2x64(trackdirs));
 
	}
 

	
src/train_cmd.cpp
Show inline comments
 
@@ -2188,10 +2188,10 @@ static Track ChooseTrainTrack(Vehicle* v
 
	TIC()
 
#endif
 

	
 
	assert((tracks & ~0x3F) == 0);
 
	assert((tracks & ~TRACK_BIT_MASK) == 0);
 

	
 
	/* quick return in case only one possible track is available */
 
	if (KILL_FIRST_BIT(tracks) == 0) return FindFirstTrack(tracks);
 
	if (KillFirstBit(tracks) == TRACK_BIT_NONE) return FindFirstTrack(tracks);
 

	
 
	if (_patches.yapf.rail_use_yapf) {
 
		Trackdir trackdir = YapfChooseRailTrack(v, tile, enterdir, tracks, &path_not_found);
src/yapf/yapf_base.hpp
Show inline comments
 
@@ -192,8 +192,8 @@ public:
 
	/** add multiple nodes - direct children of the given node */
 
	FORCEINLINE void AddMultipleNodes(Node* parent, const TrackFollower &tf)
 
	{
 
		bool is_choice = (KillFirstBit2x64(tf.m_new_td_bits) != 0);
 
		for (TrackdirBits rtds = tf.m_new_td_bits; rtds != TRACKDIR_BIT_NONE; rtds = (TrackdirBits)KillFirstBit2x64(rtds)) {
 
		bool is_choice = (KillFirstBit(tf.m_new_td_bits) != TRACKDIR_BIT_NONE);
 
		for (TrackdirBits rtds = tf.m_new_td_bits; rtds != TRACKDIR_BIT_NONE; rtds = KillFirstBit(rtds)) {
 
			Trackdir td = (Trackdir)FindFirstBit2x64(rtds);
 
			Node& n = Yapf().CreateNewNode();
 
			n.Set(parent, tf.m_new_tile, td, is_choice);
src/yapf/yapf_common.hpp
Show inline comments
 
@@ -32,8 +32,8 @@ public:
 
	/// Called when YAPF needs to place origin nodes into open list
 
	void PfSetStartupNodes()
 
	{
 
		bool is_choice = (KillFirstBit2x64(m_orgTrackdirs) != 0);
 
		for (TrackdirBits tdb = m_orgTrackdirs; tdb != TRACKDIR_BIT_NONE; tdb = (TrackdirBits)KillFirstBit2x64(tdb)) {
 
		bool is_choice = (KillFirstBit(m_orgTrackdirs) != TRACKDIR_BIT_NONE);
 
		for (TrackdirBits tdb = m_orgTrackdirs; tdb != TRACKDIR_BIT_NONE; tdb = KillFirstBit(tdb)) {
 
			Trackdir td = (Trackdir)FindFirstBit2x64(tdb);
 
			Node& n1 = Yapf().CreateNewNode();
 
			n1.Set(NULL, m_orgTile, td, is_choice);
src/yapf/yapf_costrail.hpp
Show inline comments
 
@@ -387,7 +387,7 @@ no_entry_cost: // jump here at the begin
 
			}
 

	
 
			/* Check if the next tile is not a choice. */
 
			if (KillFirstBit2x64(tf_local.m_new_td_bits) != 0) {
 
			if (KillFirstBit(tf_local.m_new_td_bits) != TRACKDIR_BIT_NONE) {
 
				/* More than one segment will follow. Close this one. */
 
				end_segment_reason |= ESRB_CHOICE_FOLLOWS;
 
				break;
src/yapf/yapf_road.cpp
Show inline comments
 
@@ -97,7 +97,7 @@ public:
 
			if (!F.Follow(tile, trackdir)) break;
 

	
 
			// if there are more trackdirs available & reachable, we are at the end of segment
 
			if (KillFirstBit2x64(F.m_new_td_bits) != 0) break;
 
			if (KillFirstBit(F.m_new_td_bits) != TRACKDIR_BIT_NONE) break;
 

	
 
			Trackdir new_td = (Trackdir)FindFirstBit2x64(F.m_new_td_bits);
 

	
0 comments (0 inline, 0 general)