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Feb 98 Challenge

Volume Number: 14 (1998)
Issue Number: 2
Column Tag: Programmer's Challenge

Programmer's Challenge

by Bob Boonstra, Westford, MA

Image Decoder

This month's Challenge is much easier to state than it will be to implement. Your task this month is to write a decoder for Graphics Interchange Format images. GIF is a data stream-oriented file format used to define the transmission protocol of LZW-encoded bitmap data. Your code will read a file containing a GIF and draw the image in an offscreen graphics world. There are two versions of the GIF specification; this Challenge includes only the earlier and more common GIF87a format, not the GIF89a format. The format description is too long to include here, but you can find the GIF87a specification at: ftp://ftp.ncsa.uiuc.edu/misc/file.formats/graphics.formats/gif87a.doc

Other useful information on graphics formats in general is available at: http://www.cis.ohio-state.edu/hypertext/faq/usenet/graphics/fileformats-faq/top.html

The prototype for the code you should write is:

#include <QDOffscreen.h>
#include <stdio.h>
GWorldPtr ReadImage(FILE *inputFile);

The inputFile will have been opened for you in binary mode by the calling routine. ReadImage should read and parse the image, create a GWorld with the appropriate color table, draw the image in the GWorld, and return a GWorld pointer to the calling routine. The solution that correctly decodes a variety of images in the least amount of execution time will be the winner.

I thought for some time about the Compuserve / Unisys / LZW patent controverty before selecting this topic for the Challenge. The LZW algorithm used in GIF compression is patented by Unisys, and Unisys requires that any commercial software product that uses this algorithm, including software that reads GIF images, requires a license from Unisys. Freely distributed software does not require a license. Since the Challenge doesn't result in a software product, much less a commercial product, I decided to go ahead with this exploration of decoding efficiency.

This will be a native PowerPC Challenge, using the latest CodeWarrior environment. Solutions must be coded in C, C++, or Pascal. This Challenge was suggested by Peter Lewis, who earns 2 Challenge points for the suggestion.

Three Months Ago Winner

Congratulations to Jeff Mallett (Boulder Creek, CA) for submitting the winning entry to the Pente(tm) Challenge. The objective was to accumulate, in minimum execution time, the most points in a round-robin tournament of the board game Pente(tm). With only three entries, the tournament required only six games for each player to compete against each other player twice, once playing first and once playing second. Both the winning entry and the third-place entry by Randy Boring employed an alpha-beta search technique to find the best move, and both entries were successful in winning most of their games. Jeff's entry, however, was more efficient about pruning the search tree and therefore required significantly less execution time than Randy's entry. Since a point was deducted for each second of execution time, the winning entry lost significantly fewer points for inefficiency. In addition, the scoring algorithm in Jeff's AddStone routine takes advantage of all three methods of scoring points: captures, winning by placing 5 stones in a row, and leaving sequences of 4-in-a-row on the board at the conclusion of a game. His solution earned more points as a result, even though it won the same number of games as Randy's.

The table below lists the number of tournament wins, points earned, cumulative score, code size, data size, and programming language for each entry. The number in parentheses after the entrant's name is the total number of Challenge points earned in all Challenges to date prior to this one.

Name               Wins   Points   Score  Code  Data  Language
Jeff Mallett (74)    3      33     32.03  4872  7923    C
Sebastian Maurer     0      10      9.97  4860  208     C++
Randy Boring (66)    3      23   -374.90  7672  2649    C

Top 20 Contestants

Here are the Top Contestants for the Programmer's Challenge. The numbers below include points awarded over the 24 most recent contests, including points earned by this month's entrants. The scores have been adjusted to correct an error made in assigning points for the Stratego Challenge printed in the November issue.

Rank Name               Points
 1.  Munter, Ernst        200  
 2.  Boring, Randy         73
 3.  Cooper, Greg          61
 4.  Lewis, Peter          59
 5.  Mallett, Jeff         50
 6.  Nicolle, Ludovic      48
 7.  Murphy, ACC           34
 8.  Gregg, Xan            33
 9.  Antoniewicz, Andy     24
10.  Day, Mark             20
11.  Higgins, Charles      20
12.  Larsson, Gustav       20
13.  Studer, Thomas        20
14.  Gundrum, Eric         15
15.  Hart, Alan            14
16.  O'Connor, Turlough    14
17.  Picao, Miguel Cruz    14
18.  Saxton, Tom           12
19.  Cutts, Kevin          11
20.  8-way tie             10

There are three ways to earn points: (1) scoring in the top 5 of any Challenge, (2) being the first person to find a bug in a published winning solution or, (3) being the first person to suggest a Challenge that I use. The points you can win are:

1st place            20 points
2nd place            10 points
3rd place             7 points
4th place             4 points
5th place             2 points
finding bug           2 points
suggesting Challenge  2 points

Here is Jeff's winning solution:

MyPente.c
Copyright © 1997 Jeff Mallett
//
// Do a depth=1 search to sort moves. Then do a higher
// depth alpha-beta search to select the best move.
//
// Plays for score rather than to win. For example,
// doesn't try to win by getting 5 captures since
// there is no score incentive for this. It could be
// retuned to play for a win instead.

#include "Pente.h"

#define SEARCH_DEPTH 4
enum {
 _FRIEND = 0x0001,
 _ENEMY = 0x0002,
 _EMPTY = 0x0004,
 _WALL  = 0x0008
};

#define BORDER    1
#define BORDERS    2
#define INFINITY   32600
#define NA      0
#define MAX_CELLS   (31 + BORDERS) * (31 + BORDERS)

#define ESTIMATE_PLUS 1
#define WIN      2000
#define CAPTURE_SCORE 240
#define VULNERABLE   150

static short CHAIN_SCORE2[3][3] = {  //[color][open]
 { NA, NA, NA },
 { -1, -9, -2 },      // FRIEND
 { 1, 9, 2 }      // ENEMY
};
static short CHAIN_SCORE3[3][3] = {  //[color][open]
 { NA, NA, NA },
 { 3, 16, 40 },      // FRIEND
 { -2,-10,-30 }      // ENEMY
};
static short CHAIN_SCORE4[3][3] = {  //[color][open]
 {  NA, NA, NA },
 { 230, 240, 250 },  // FRIEND
 { -150,-155,-160 }  // ENEMY
};
static short CHAIN_SCORE5[3] = {    //[color]
 NA, WIN, -WIN
};
//                 1  2  3  4
static short BLOCK_SCORE[5] = { NA, 0, 14, 14, 22};
static short THREATS[] = {
 NA, NA,
 25, // 2: tria
 30, // 3: half-open four
 350, // 4: double trias
 370, // 5: tria + half-open four
 450, // 6: tessera or 2 half-open fours
 500, 500, 500, 500, 500, 500, 500, 500, 500, 500
};

static short gPreScore[MAX_CELLS], gEstimates[MAX_CELLS];
static short *gEstimatesStart, *gEstimatesEnd;
static short gBoard[MAX_CELLS], *gBoardStart, *gBoardEnd;
static short *gFirstStone, *gLastStone;
static short *gKillers[SEARCH_DEPTH], gPreviousThreats;
static short gDirections[8], *gDirectionsEnd;
static short gMoveNum, gScore, gStartDepth;
static short gBoardHalfSize, gSideLength, gBoardMax;
static short gCumCapturesFriend, gCumCapturesEnemy;
static short gAdjustment, gSE;

#define ADJUST(a)    ( (a) + gAdjustment )
#define TRANSLATE(x, y) \
 (gSideLength * ADJUST(y) + ADJUST(x))
#define GET_INDEX(p) ((p) - gBoard)
#define GET_X(i)   ( ((i) % gSideLength) - gAdjustment )
#define GET_Y(i)   ( ((i) / gSideLength) - gAdjustment )
#define UPDATE_ENDPOINTS(pSq, a, b) \
 if (pSq < a) a = pSq; \
 if (pSq > b) b = pSq

#define OPPONENT(side) (3 - (side))
#define OCCUPIED(x)   ((x) & (_FRIEND | _ENEMY))
#define EMPTY(x)    ((x) == _EMPTY)

// gChanges -- Array of unsigned longs containing data to
// undo moves
//   list of:
//     <pointer to position> <old position value>
//   terminated by a OL
static unsigned long gChanges[256], *gChangesEnd;
#define PUSH(x)    *(gChangesEnd++) = (x)
#define START_SAVE  PUSH(0L)
#define PUSH_SQ(pSq) \
  { PUSH((long)*(pSq)); PUSH((unsigned long)(pSq)); }
#define POP      *(--gChangesEnd)
#define TOP      *gChangesEnd

static short * ChooseNextMove();
static short AddStone(short alpha, short beta, short *pSq,
        short color, short depth,
        short capturesFriend, short capturesEnemy,
        short *firstStone, short *lastStone);
static long MyFindCaptures(Capture capture[], short *pSq,
        short us, short them);
static Boolean MyFindFive(short *pSq, short color);

InitPente
void InitPente(
 long boardHalfSize  /* e.g., 9 for a 19x19 board */
       /* all coordinates between -boardHalfSize
        and +boardHalfSize */
) {
 short i, j, *pSq;
 
 gBoardHalfSize = boardHalfSize;
 gSideLength = boardHalfSize * 2 + 1 + BORDERS;
 gSE = gSideLength + 1;
 gDirections[0] = -gSE;                // NW
 gDirections[1] = -gSideLength;        // N
 gDirections[2] = -gSideLength + 1;     // NE
 gDirections[3] = -1;                // W
 gDirections[4] = gSE;                // SE
 gDirections[5] = gSideLength;        // S
 gDirections[6] = gSideLength - 1;      // SW
 gDirections[7] = 1;                  // E
 gDirectionsEnd = &gDirections[8];
 
 gBoardMax = gSideLength * gSideLength;
 i = (gSideLength + 1) * BORDER;
 gBoardStart = &gBoard[i];
 gBoardEnd = &gBoard[gBoardMax - i];
 gEstimatesStart = &gEstimates[i];
 gEstimatesEnd = &gEstimates[gBoardMax - i];
 gFirstStone = gBoardEnd;
 gLastStone = gBoardStart;
 
 pSq = gBoard;
 do {
  *pSq = _WALL;
 } while (++pSq != gBoardStart);
 do {
  *pSq = _EMPTY;
 } while (++pSq != gBoardEnd);
 do {
  *pSq = _WALL;
 } while (++pSq < &gBoard[gBoardMax]);
 for (i = BORDER + boardHalfSize * 2 + 1;
    i<gBoardMax-gSideLength; i += gSideLength)
  for (j=0; j<BORDERS; ++j)
   gBoard[i+j] = _WALL;
 gCumCapturesFriend = gCumCapturesEnemy = gMoveNum = 0;
 gAdjustment = gBoardHalfSize + BORDER;
 gStartDepth = SEARCH_DEPTH - 1;
}

Pente
void Pente(
 Point opponentsMove,      /* your opponent moved here */
 Boolean playingFirst,      /* ignore opponentMove */
 Point *yourMove,          /* return your move here */
 Capture claimCaptures[],    /* return captured pairs here */
 long *numCaptures,       /* return # of claimCaptures */
 Boolean *claimVictory     /* return true if you claim
               victory with this move */
) {
 Point move;
 Capture opponentCaptures[8];
 
 short *pSq, *pNewSq, *d;
 short score, bestScore, i;
 short *pBestMove;
 
 *numCaptures = 0;
 *claimVictory = false;
 if (playingFirst) { // *** MOVE 1
  move.h = move.v = 0;
  pSq = &gBoard[TRANSLATE(0, 0)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 1;
  return;
 }
 
 i = TRANSLATE(opponentsMove.h, opponentsMove.v);
 pSq = &gBoard[i];
 *pSq = _ENEMY;
 UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
 ++gMoveNum;

 if (gMoveNum == 1) { // *** MOVE 2
  move.h = move.v = -2;
  pSq = &gBoard[TRANSLATE(-2, -2)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 2;
  return;
 }
 
 if (gMoveNum == 2) { // *** MOVE 3
  if (opponentsMove.v < opponentsMove.h) {
   if (opponentsMove.v < -opponentsMove.h) {
    // top triangle
    move.h = 0;
    move.v = 4;
   } else {
    // right triangle
    move.h = -4;
    move.v = 0;
   }
  } else {
   if (opponentsMove.v >= -opponentsMove.h) {
    // bottom triangle
    move.h = 0;
    move.v = -4;
   } else {
    // left triangle
    move.h = 4;
    move.v = 0;
   }
  }
  pSq = &gBoard[TRANSLATE(move.h, move.v)];
  *pSq = _FRIEND;
  UPDATE_ENDPOINTS(pSq, gFirstStone, gLastStone);
  *yourMove = move;
  gMoveNum = 3;
  return;
 }

 gChangesEnd = gChanges;
 gCumCapturesEnemy +=
   MyFindCaptures(opponentCaptures, &gBoard[i],
           _ENEMY, _FRIEND);
 for (pSq = gEstimatesStart; pSq != gEstimatesEnd; ++pSq)
  *pSq = 0;
 for (pSq = gFirstStone; pSq <= gLastStone; ++pSq)
  if (OCCUPIED(*pSq)) {
   d = gDirections;
   do {
    pNewSq = pSq + *d;
    if (EMPTY(*pNewSq)) {
     gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     pNewSq += *d;
     if (EMPTY(*pNewSq)) {
      gEstimates[GET_INDEX(pNewSq)] += ESTIMATE_PLUS;
     }
    }
   } while (++d != gDirectionsEnd);
  }

 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
  if (gEstimates[GET_INDEX(pSq)]) {
   i = GET_INDEX(pSq);
   gScore = gEstimates[i];
   gPreScore[i] = AddStone(-INFINITY, INFINITY, pSq,
            _FRIEND, 0, gCumCapturesFriend,
            gCumCapturesEnemy, gFirstStone,
            gLastStone);
  }

 for (i=0; i<SEARCH_DEPTH; ++i)
  gKillers[i] = NULL;
 bestScore = -INFINITY;
 pBestMove = NULL;
 pSq = ChooseNextMove();
 while (pSq) {
  i = GET_INDEX(pSq);
  gScore = gEstimates[i];
  score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
       gStartDepth, gCumCapturesFriend,
       gCumCapturesEnemy, gFirstStone, gLastStone);
  gEstimates[i] = -1; // searched
  if (score > bestScore) {
   bestScore = score;
   pBestMove = pSq;
  }
  pSq = ChooseNextMove();
 }
  
 if (bestScore == -INFINITY) {
  for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq)
   if (EMPTY(*pSq) && !gEstimates[GET_INDEX(pSq)]) {
    gScore = 0;
    score = AddStone(-INFINITY, -bestScore, pSq, _FRIEND,
                  gStartDepth, gCumCapturesFriend,
                  gCumCapturesEnemy, gFirstStone, gLastStone);
    if (score > bestScore) {
     bestScore = score;
     pBestMove = pSq;
    }
   }
  if (bestScore == -INFINITY) {
   DebugStr("\p no move found - Pente");
   return; //no move
  }
 }
 
 *pBestMove = _FRIEND;
 UPDATE_ENDPOINTS(pBestMove, gFirstStone, gLastStone);
 i = GET_INDEX(pBestMove);
 move.h = GET_X(i);
 move.v = GET_Y(i);
 *yourMove = move;
 ++gMoveNum;
 // find captures
 *numCaptures = MyFindCaptures(claimCaptures, pBestMove,
          _FRIEND, _ENEMY);
 gCumCapturesFriend += *numCaptures;
 if (gCumCapturesFriend >= 5) {
  *claimVictory = true;
 } else {
  *claimVictory = MyFindFive(pBestMove, _FRIEND);
 }
}

TermPente
void TermPente(void) { }

ChooseNextMove
short * ChooseNextMove()
{
 short i, *pSq;
 short *found = NULL;
 short high = -INFINITY;
 for (pSq = gBoardStart; pSq != gBoardEnd; ++pSq) {
  i = GET_INDEX(pSq);
  if (gEstimates[i] > 0 && gPreScore[i] > high) {
   found = pSq;
   high = gPreScore[i];
  }
 }
 return found;
}

AddStone
// Alpha-beta search routine
// returns score of how good it is for color
// alpha and beta apply for the opponent after the move
// is made
// gScore is absolute: + for _FRIEND
short AddStone(short alpha, short beta, short *pSq,
    short color, short depth, short capturesFriend,
    short capturesEnemy, short *firstStone,
    short *lastStone)
{
 register short *pNewSq, *d;
 short x, bestScore, t, *pEnd;
 short open, *killer;
 short threats, blocks, vulnerable;
 short opponent = OPPONENT(color);
 short saveScore = gScore;
  
 START_SAVE;
 threats = blocks = vulnerable = 0;
 d = gDirections;
 do {
  pNewSq = pSq + *d;
  
  if (*pNewSq == color) { // Next to friend
   if (d <= &gDirections[3]) {
    x = 1;
    open = 0;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     open = 1;
    for (pNewSq = pSq + *(d+4); *pNewSq == color;
       pNewSq += *(d+4))
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   } else {
    t = *(pSq + *(d-4));
    if (t == color)
     continue;
    x = 1;
    open = 0;
    if (EMPTY(t))
     open = 1;
    for (pNewSq += *d; *pNewSq == color; pNewSq += *d)
     ++x;
    if (EMPTY(*pNewSq))
     ++open;
   }
   
   switch (x) {
    case 1:  // 2-in-a-row
     gScore += CHAIN_SCORE2[color][open];
     if (open == 1)
      ++vulnerable;
     break;
    case 2:  // 3-in-a-row
     gScore += CHAIN_SCORE3[color][open];
     if (open == 2)
      threats += 2;        // tria = 2
     break;
    case 3:  // 4-in-a-row
     gScore += CHAIN_SCORE4[color][open];
     threats += open * 3;  // tessera = 6, half-open = 3
     break;
    default:  // 5-in-a-row (or more)
     gScore += CHAIN_SCORE5[color];
     threats = -99;        // game over
     break;
   }
   
  } else if (*pNewSq == opponent) {  // Next to enemy
   x = 1;
   for (pNewSq += *d; *pNewSq == opponent; pNewSq += *d)
    ++x;
    
   if (EMPTY(*pNewSq)) {
    blocks += BLOCK_SCORE[x];
   } else if (x == 2 && *pNewSq == color) {
    t = CAPTURE_SCORE;
    if (color != _FRIEND)
     t = -t;
    gScore += t;
    if (color == _FRIEND) {
     if (++capturesFriend >= 5) {
      threats = -99;  // game over
     }
    } else {  // color == _ENEMY
     if (++capturesEnemy >= 5) {
      threats = -99;  // game over
     }
    }
    if (depth) {
     pNewSq = pSq + *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
     pNewSq += *d;
     PUSH_SQ(pNewSq);
     *pNewSq = _EMPTY;
    }
   }
  }
 } while (++d != gDirectionsEnd);
  
 if (threats < 0) {
  // Game over
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;
  goto RESTORE;
 }
   
  // Not forced to make a bad move
 if (color == _FRIEND) {
  if (gScore < saveScore)
   gScore = saveScore;
 } else if (gScore > saveScore)
  gScore = saveScore;
 if (depth) {
  // Add stone
  PUSH_SQ(pSq);
  *pSq = color;
  UPDATE_ENDPOINTS(pSq, firstStone, lastStone);
  --depth; 
  gPreviousThreats = threats;
  bestScore = -INFINITY;
  // Killer move?
  killer = gKillers[depth];
  if (killer && EMPTY(*killer)) {
   saveScore = gScore;
    bestScore = AddStone(-beta, -alpha, killer,
           opponent, depth, capturesFriend,
           capturesEnemy, firstStone, lastStone);
   gScore = saveScore;
   if (bestScore > alpha) {
    if (bestScore >= beta) {
     bestScore = -bestScore;
     goto RESTORE;
    }
    alpha = bestScore;
   }
  }
  
  pEnd = lastStone + gSE;
  if (pEnd >= gBoardEnd)
   pEnd = gBoardEnd - 1;
  pSq = firstStone - gSE;
  if (pSq < gBoardStart)
   pSq = gBoardStart;
  do {
   if (EMPTY(*pSq) && pSq != killer) {
    d = gDirections;
    do {
     pNewSq = pSq + *d;
     if (OCCUPIED(*pNewSq) &&
        (*(pNewSq + *d) == *pNewSq ||
         *(pSq  - *d) == *pNewSq))
      break;
    } while (++d != gDirectionsEnd);
    if (d != gDirectionsEnd) {
     saveScore = gScore;
      t = AddStone(-beta, -alpha, pSq, opponent,
         depth, capturesFriend, capturesEnemy,
         firstStone, lastStone);
     gScore = saveScore;
     if (t > bestScore) {
      bestScore = t;
      if (t > alpha) {
       if (t >= beta) {
        gKillers[depth] = pSq;
        break;
       }
       if (depth >= gStartDepth-1)
        gKillers[depth] = pSq;
       alpha = t;
      }
     }
    }
   }
  } while (++pSq <= pEnd);
  if (bestScore == -INFINITY) {
   ++depth;
   goto TERMINAL;
  }
  bestScore = -bestScore;
  
 } else { // !depth
TERMINAL:
  bestScore = gScore;
  if (color != _FRIEND)
   bestScore = -bestScore;

  // Winning threats
  if (gPreviousThreats >= 5) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats >= 5) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats == 4) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats == 4) {
   bestScore += THREATS[threats];
  } else if (gPreviousThreats) {
   bestScore -= THREATS[gPreviousThreats];
  } else if (threats) {
   bestScore += THREATS[threats];
  }
  bestScore += blocks - vulnerable * VULNERABLE;
 }
 
RESTORE: 
 while (POP) {
  pSq = (short *)TOP;
  *pSq = POP;
 }
  
 return bestScore;
}

MyFindCaptures
long MyFindCaptures(Capture capture[], short *pSq,
          short us, short them)
{
 short i, *p1, *p2;
 short myCaptures = 0;
 short *d = gDirections;
 
 do {
  p1 = pSq + *d;
  if (*p1 == them) {
   p2 = p1 + *d;
   if (*p2 == them && *(p2 + *d) == us) {
    *p1 = *p2 = _EMPTY;
    i = GET_INDEX(p1);
    capture[myCaptures].stone1.h = GET_X(i);
    capture[myCaptures].stone1.v = GET_Y(i);
    i = GET_INDEX(p2);
    capture[myCaptures].stone2.h = GET_X(i);
    capture[myCaptures].stone2.v = GET_Y(i);
    ++myCaptures;
   }
  }
 } while (++d != gDirectionsEnd);
 return myCaptures;
}

MyFindFive
Boolean MyFindFive(short *pSq, short color)
{
 short x, *d, *pNewSq, i;
 
 d = gDirections;
 i = 0;
 do {
  x = 1;
  for (pNewSq = pSq + *d; *pNewSq == color; pNewSq += *d)
   ++x;
  for (pNewSq = pSq + *(d+4); *pNewSq == color;
     pNewSq += *(d+4))
   ++x;
  if (x >= 5)
   return true;
  ++d;
 } while (++i < 4);
 return false;
}
 

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WALTR is designed to make it easy to upload and convert any music or video file to an iPad or iPhone format for native playback. It supports a huge variety of media file types, including MP3, MP4,... Read more
Audio Hijack 3.1 - Record and enhance au...
Audio Hijack (was Audio Hijack Pro) drastically changes the way you use audio on your computer, giving you the freedom to listen to audio when you want and how you want. Record and enhance any audio... Read more
PopChar 7.1 - Floating window shows avai...
We're also selling a 5-license family pack for only $25.99! PopChar helps you get the most out of your font collection. With its crystal-clear interface, PopChar X provides a frustration-free way to... Read more
BBEdit 11.1.1 - Powerful text and HTML e...
BBEdit is the leading professional HTML and text editor for the Mac. Specifically crafted in response to the needs of Web authors and software developers, this award-winning product provides a... Read more
Picasa 3.9.139 - Organize, edit, and sha...
Picasa and Picasa Web Albums allows you to organize, edit, and upload your photos to the Web from your computer in quick, simple steps. Arrange your photos into folders and albums and erase their... Read more
Mac DVDRipper Pro 5.0.5 - Copy, backup,...
Mac DVDRipper Pro is the DVD backup solution that lets you protect your DVDs from scratches, save your batteries by reading your movies from your hard disk, manage your collection with just a few... Read more
NetShade 6.2 - Browse privately using an...
This promotion is for NetShade and 1 year of Proxy and VPN services NetShade is an anonymous proxy and VPN app+service for Mac. Unblock your Internet through NetShade's high-speed proxy and VPN... Read more

Block Fortress has a Big New Update for...
Block Fortress is a survival-style game that's as fun as it is blocky. It's also just gotten a rather sizeable update that adds a lot more cool stuff. [Read more] | Read more »
Simple and Surreal Star Base Sim rymdkap...
I really like rymdkapsel. Not just because I'm a sucker for games that are cleverly simple or highly stylisitc, but because it's fun and challenging. Actually it's extremely challenging, which is why I was excited to learn that it's getting a couple... | Read more »
Check out the anticipated Angel Stone in...
Fincon has finally revealed Angel Stone in action in the first ever official gameplay trailer for the anticipated hack and slasher. Angel Stone is set in a post-apocalyptic world in which humanity is in danger of being wiped out by the demonic... | Read more »
Moleskine Timepage is an All-New Calenda...
Moleskine Timepage is a bit of a departure for the notebook manufacturer (since it has little to do with notebooks), but it certainly carries their simple and elegant style quite well. [Read more] | Read more »
Jog on Over and Check Out the New Runtas...
Runtastic has put out a fair number of apps to help you sleep, track excercise, and train various parts of your body. Now it's time for your legs to have their own time in the spotlight with Runtastic Leg Trainer. [Read more] | Read more »
It's Lights Out in the Upcoming Pla...
Ember’s Journey is a stark puzzle platformer with a twist: the entire game is played in darkness. The only light you can see by is the one emanating from your own character. [Read more] | Read more »
MooVee - Your Movies Guru (Entertainmen...
MooVee - Your Movies Guru 1.0 Device: iOS iPhone Category: Entertainment Price: $1.99, Version: 1.0 (iTunes) Description: MooVee helps you effortlessly manage your movies, on your iPhone. | Read more »
Geometry Wars 3: Dimensions (Games)
Geometry Wars 3: Dimensions 1.0.0 Device: iOS Universal Category: Games Price: $4.99, Version: 1.0.0 (iTunes) Description: Enjoy the next chapter in the award-winning Geometry Wars franchise and enjoy stunning, console-quality... | Read more »
CHAOS RINGS Ⅲ (Games)
CHAOS RINGS Ⅲ 1.0.0 Device: iOS Universal Category: Games Price: $19.99, Version: 1.0.0 (iTunes) Description: The newest addition to the popular smartphone RPG series is finally here! ・CHAOS RINGS Overview | Read more »
The Popular Insight Series of Travel Gui...
Getting around in a country when you can't understand the primary language can be tough. Fortunately there are several options available to help wold travellers with the important stuff like giving directions to a cab driver or asking where the... | Read more »

Price Scanner via MacPrices.net

Top Markets Saturation To Slow Global Smartph...
According to a new mobile phone forecast from the International Data Corporation (IDC) Worldwide Quarterly Mobile Phone Tracker, smartphone shipments are expected to grow 11.3% in 2015 — down from 27... Read more
Apple refurbished 2014 13-inch Retina MacBook...
The Apple Store has Apple Certified Refurbished 2014 13″ Retina MacBook Pros available for up to $400 off original MSRP, starting at $979. An Apple one-year warranty is included with each model, and... Read more
What Would the ideal Apple Productivity Platf...
For the past four years I’ve kept a foot in both the Mac and iPad camps respectively. my daily computing hours divided about 50/50 between the two devices with remarkable consistency. However, there’... Read more
PageMeUp 1.2.1 Ten Dollar Page Layout Applica...
Paris, France-based Softobe, an OS X software development company, has announced that their PageMeUp v. 1.2.1, is available on the Mac App Store for $9.99. The license can be installed on up to 5... Read more
Eight New Products For USB Type-C Application...
Fresco Logic, specialists in advanced connectivity technologies and ICs, has introduced two new product families targeting the Type-C connector recently introduced across a number of consumer... Read more
Scripps National Spelling Bee Launches Buzzwo...
Scripps National Spelling Bee fans can monitor the action at the 2015 Spelling Bee with the new Buzzworthy app for iOS, Android and Windows mobile devices. The free Buzzworthy app provides friendly... Read more
13-inch 2.5GHz MacBook Pro on sale for $120 o...
B&H Photo has the 13″ 2.5GHz MacBook Pro on sale for $979 including free shipping plus NY sales tax only. Their price is $120 off MSRP, and it’s the lowest price for this model (except for Apple’... Read more
27-inch 3.3GHz 5K iMac on sale for $1899, $10...
B&H Photo has the new 27″ 3.3GHz 5K iMac on sale for $1899.99 including free shipping plus NY tax only. Their price is $100 off MSRP. Read more
Save up to $50 on iPad Air 2, NY tax only, fr...
B&H Photo has iPad Air 2s on sale for up to $50 off MSRP including free shipping plus NY sales tax only: - 16GB iPad Air 2 WiFi: $469 $30 off - 64GB iPad Air 2 WiFi: $549.99 $50 off - 128GB iPad... Read more
Updated Mac Price Trackers
We’ve updated our Mac Price Trackers with the latest information on prices, bundles, and availability on systems from Apple’s authorized internet/catalog resellers: - 15″ MacBook Pros - 13″ MacBook... Read more

Jobs Board

*Apple* Retail - Multiple Positions (US) - A...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
Program Manager, *Apple* Community Support...
**Job Summary** Apple Support Communities ( discussions. apple .com) helps customers get the most from their Apple products and services by providing access to Read more
Senior Data Scientist, *Apple* Retail - Onl...
**Job Summary** Apple Retail - Online sells Apple products to customers around the world. In addition to selling Apple products with unique services such as iPad Read more
*Apple* Solutions Consultant - Retail Sales...
**Job Summary** As an Apple Solutions Consultant (ASC) you are the link between our customers and our products. Your role is to drive the Apple business in a retail Read more
*Apple* Watch SW Application Project Manager...
**Job Summary** The Apple Watch software team is looking for an Application Engineering Project Manager to work on new projects for Apple . The successful candidate Read more
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