TweetFollow Us on Twitter

Line Art Rotation
Volume Number:6
Issue Number:5
Column Tag:C Forum

Related Info: Quickdraw

Line Art Rotation

By Jeffrey J. Martin, College Station, TX

Note: Source code files accompanying article are located on MacTech CD-ROM or source code disks.

[ Jeff Martin is a student at Texas A&M University working on his bachelors in computer science. He has been a personal computer technician at the campus computer center, a system operator on the campus mainframes, and now freelances graphic work for various professors. He hopes that one day a motion picture computer animation company will take him away from all of this.]

This being my first stab at an article, I will try to keep it short while leaving in all of the essential vitamins and nutrients. In that spirit my user interface will bring back nostalgic thoughts to those past Apple II and TRS-80 users, and any PC people will feel right at home.

The essence of this program is to show how a seemingly complicated transformation and rotation can be applied to an array of points that form any arbitrary line art.

Of course to form a transformation on the array of points (e.g. offset the points to the left) we simply add some delta x(dx) and/or delta y(dy) to every point:

/* 1 */

for(i=0;i<numofpoints;i++)
  {points[i].h+=dx;points[i].v+=dy;}

Now rotation is a little harder, but to spare you the heartache, it can be shown that for rotation about the origin(fig 1):

So the trick of rotating about some arbitrary point is to first transform that pivot point to be the origin(transforming every other point by the save amount). Second, perform the rotation of all points by the angle theta. Third, transform the pivot back(once again transforming all other points as well).

Now all of this may seem to be a costly maneuver, but the fact is that we can roll all of these into a single matrix multiplication, using homogeneous coordinates:

where

form one matrix.

Fig. 2 shows the multiplication of a homogeneous coordinate and a translation matrix. Please verify that this results in (X+dx,Y+dy) (if unfamiliar with matrix multiplication see mult procedure in program).

Similarly figure 3 shows multiplication with a rotation matrix - an exact translation of our rotation equations in matix form.

So the translation, rotation, and inverse translation matrices are as shown in figure 4. Which forms one matrix to be multiplied times the vertices.

The following program allows the user to enter in points with the mouse until a key is pressed. At that time the user then uses the mouse to enter a pivot point. The program uses the pivot point to form the translation and inverse translation matrices(from the x and y coordinates). The program then forms a rotation matrix of a constant rotation angle(Π/20) and calculates the new vertices based on the values of the old ones. The program undraws the old lines and redraws the new and calculates again until the object has rotated through a shift of 4Π(2 rotations). press the mouse button again to exit program.

Once again, I point out that the code does not follow the user guidelines, but then it is not exactly meant to be an application in itself. Build your own program around it and see what you can do. One suggestion is to cancel the erasing of the object to achieve spirograph patterns. I think too many of the submissions to MacTutor contain an interface that we all know too well, and for those just interested in the algorithms it can mean a lot of extra work. Have Fun.

/* 2 */

#include<math.h>
int errno;

void mult();  /*out matrix mult proc*/
/*floating value of points to avoid roundoff*/
typedef struct rec {float h,v;} points;
main()
{
  int buttondown=0, /*flagg for mouse       */
      n=-1,         /*number of vertices    */
      keypressed=0, /*flagg for key         */
      flip=0,       /*to allow alternating  */
      flop=1,       /*vertices to be drawn  */
      i;            /*array counter         */
  float x,          /*angle counter         */
      T[3][3],      /*translation matrix    */
      Tinv[3][3],   /*translate back        */
      Rz[3][3],     /*rotate matrix         */
      c[3][3],      /*result of T&R         */
      d[3][3];      /*result of c&Tinv      */
  long curtick,     /*for delay loop        */
       lastick;     /*for delay loop        */
  EventRecord nextevent;/*to get mouse&key  */
  Point origin,dummy;   /*pivot and locator */
  points points[2][30];/*vertices(don’t draw Eiffel tower)  */
  WindowPtr scnwdw;    /*window pointer     */
  Rect      scnrect;   /*window rect        */
/*************************************
*  Set things up                     *
*************************************/
InitGraf(&thePort);
InitFonts();
InitWindows();
InitDialogs((Ptr)0L);
TEInit();
InitMenus();
scnrect=screenBits.bounds;
InsetRect(&scnrect,10,25);
scnwdw=NewWindow(0,&scnrect,”\p”,TRUE,dBoxProc, -1,FALSE,0);
SetPort(scnwdw);
InitCursor();
  
/*************************************
*  Get points                        *
*************************************/
  while(!keypressed)
  {
    buttondown=0;
    SystemTask();
    if(GetNextEvent(-1,&nextevent))
      if(nextevent.what==mouseDown) buttondown=1;
      else if(nextevent.what==keyDown) keypressed=1;
    if(buttondown) /*get a point and draw it*/ 
    {
      GetMouse(&dummy);
      points[0][++n].h=dummy.h;points[0][n].v=dummy.v; 
      if(n==0)
        MoveTo((int)points[0][0].h,(int)points[0][0].v);
      LineTo((int)points[0][n].h,(int)points[0][n].v);
    } /*end of get point*/
  }  /*end of get points*/
  
/*************************************
*  Get origin                        *
*************************************/
  buttondown=0;
  do
  {
    SystemTask();
    if(GetNextEvent(-1,&nextevent))
      if(nextevent.what==mouseDown) buttondown=1;
  }while(!buttondown);
  GetMouse(&origin);
  
/*************************************
*  Make translation matrix           *
*************************************/
  T[0][0]=1;T[0][1]=0;T[0][2]=0;
  T[1][0]=0;T[1][1]=1;T[1][2]=0;
  T[2][0]=-origin.h;T[2][1]=-origin.v;T[2][2]=1;
  Tinv[0][0]=1;Tinv[0][1]=0;Tinv[0][2]=0;
  Tinv[1][0]=0;Tinv[1][1]=1;Tinv[1][2]=0;
  Tinv[2][0]=origin.h;Tinv[2][1]=origin.v;Tinv[2][2]=1;
  Rz[0][2]=0;Rz[1][2]=0;Rz[2][0]=0;Rz[2][1]=0;Rz[2][2]=1;
/*************************************
*  Rotate                            *
*************************************/
  x=0.157;  /*rotation angle - about 9 degrees*/
  Rz[0][0]=Rz[1][1]=cos(x);Rz[0][1]=sin(x);
  Rz[1][0]=-Rz[0][1];
  mult(T,Rz,c);
  mult(c,Tinv,d);
  for(x=.157;x<=12.56;x+=0.157)
  {
    flip++;flip=flip%2;flop++;flop=flop%2;
    for(i=0;i<=n;i++)
    {
      points[flip][i].h=points[flop][i].h*d[0][0]
                    +points[flop][i].v*d[1][0]+1*d[2][0];
      points[flip][i].v=points[flop][i].h*d[0][1]
                    +points[flop][i].v*d[1][1]+1*d[2][1];
    }  /*end update points*/
    ForeColor(whiteColor);  /*undraw flop*/
    lastick=TickCount(); /*time delay for retace to improve animation*/
    do{curtick=TickCount();} while(lastick+1>curtick);
    MoveTo((int)points[flop][0].h,(int)points[flop][0].v);
    for(i=1;i<=n;i++) LineTo((int)points[flop][i].h,(int)points[flop][i].v);
    ForeColor(blackColor);  /*draw flip*/
    lastick=TickCount();    
    do{curtick=TickCount();} while(lastick+1>curtick);
    MoveTo((int)points[flip][0].h,(int)points[flip][0].v);
    for(i=1;i<=n;i++) LineTo((int)points[flip][i].h,(int)points[flip][i].v);
  }  /*end rotate*/
    
/*************************************
*  End everything                    *
*************************************/
  buttondown=0;
  do
  {
    SystemTask();
    if(GetNextEvent(-1,&nextevent))
      if(nextevent.what==mouseDown) buttondown=1;
  }while(!buttondown);
DisposeWindow(scnwdw);
}  /*program end*/

void mult(A,B,C)
  float A[][3],B[][3],C[][3];
{
  int i,j,k;
  
  for(i=0;i<=2;i++)
    for(j=0;j<=2;j++)
    {
      C[i][j]=0.0;
      for(k=0;k<=2;k++)
        C[i][j]+=A[i][k]*B[k][j];
    }
}  /*end mult*/

3D Modeling & Rotation

The main thrust of this exercise is to extend the line art rotation into 3D object rotation using the same techniques as the 2D, while also implementing parallel projection as our means of 3D modeling.

The first part of the exercise requires that we define an object in a structure that we can easily manipulate. Using a cube for simplicity, we will start by defining the center of the cube and an array of vertices, vertex[2][# of pts] (see GetPoints in program). Referring to fig. 1, each vertex corresponds to a corner of the cube. The second dimension of the array is to provide a destination for transformed vertices. Having both sets will allow us to undraw and immediately redraw the shape - minimizing the hangtime between redrawing allows for smoother animation.

Figure 1.

Next let us construct an array of lines connecting these vertices. Each element of the line array refers to the index of the beginning and ending vertex of that particular line. This array will never change. Think of when you roll a die - the edges still go between the same corners, but the position of the corners has changed.

The next construct is the translation and inverse translation matrixes. As in 2D rotation, we must transform our local center of rotation to the origin, rotate, then translate back.

The idea of homogeneous coordinates was introduced in the last article and is now extended into 3D by adding a fourth term. Fig. 2 shows our homogeneous coordinate as a 1x4 matrix times our translation matrix(4x4). The purpose of this multiplication is to add a dx, dy and dz to every point, in order to center our vertices about the origin. Please verify that the matrix multiplication results in X+dx,Y+dy,Z+dz (if unfamiliar with matrix multiplication see matmult in program).

Figure 2.

Now we once again reach the challenging concept of rotation. Although similar to 2D, we now have the option of rotating around the X and Y as well as the Z-axis.

The simplest, rotation about the z-axis, is just as in our 2D rotations, because none of the z-values change. If this is hard to understand, think about this: if you look straight down a pencil with the point a foot away from you and spin it a half turn, the point is still a foot away, but the writing is now on the other side. The equations for the changes in the X and Y are as follows:

  Xnew=XoldCos(Ø) + YoldSin(Ø)
  Ynew=-XoldSin(Ø) + YoldCos(Ø)

The 3D representation in matrix form with a vertex multiplication is in fig. 3. And the proof of all this is in that dusty old trigonometry book up on your shelf. (once again direct multiplication of fig. 3 will yield the preceding equations).

Figure 3.

Similarly rotation about the X axis changes none of the x-values, and rotation about Y changes none of the y-values. The transformation equations are given as follows:

Rotation about the X:

 Ynew=YoldCos(Ø) + ZoldSin(Ø)
 Znew=-YoldSin(Ø)+ZoldCos(Ø)

Rotation about the Y:

   Xnew=XoldCos(Ø) - ZoldSin(Ø)
 Znew=XoldSin(Ø) + ZoldCos(Ø)

The corresponding matrices are shown in figures 4 and 5.

Figure 4.

Figure 5.

Once again we will construct a new array of vertices from a single transformation matrix formed from the translation to the origin, rotation about an axis, and translation back. Therefore creating the new vertices:

 Vnew=Vold*T*Rz*Tinv

or after combining T*Rz*Tinv into a single Master Transformation(MT):

 Vnew=Vold*MT

Finally the trick of parallel projection when viewing an object from down the Z axis is that all you have to do is draw lines between the x,y components of the points (ignore the z). For those mathematically inclined, you will realize that this is just the projection of those 3D lines on the X-Y plane (see fig. 6).

Figure 6.

The particular stretch of code I’ve included implements this transformation on the cube for rotation along the X and Y axes of the center of the cube using the arrow keys. The successive transformations of the vertices are loaded into the flip of the array (vertex[flip][pnt.#]). Then the flop is undrawn while the flip is drawn as mentioned previously and flip and flop are changed to their corresponding 0 or 1.

After launching, the application immediately draws the cube and then rotates it in response to the arrows. The program exits after a single mouse click.

Once again the code is not intended to match up to the guidelines - but is intended for use with other code or simple instructional purposes. It is concise as possible and should be easy to type in. A quick change to numofpts and numoflines as well as your own vertex and and line definitions would allow you to spin your favorite initial into its most flattering orientation.

The inspiration for this program came from the floating couch problem presented in Dirk Gently’s Holistic Detective Agency, by Douglas Adams. If enough interest is shown, perhaps a future article would include hidden line removal and color rendering techniques. After all, it was a red couch.

One last suggestion for those truly interested is to pull your shape definition in from a 3D cad program that will export in text format, such as Super 3D or AutoCad.

Anyway, on with the show

/* 3 */

#include<math.h>
/* Following is inline macro for drawing lines */
#define viewpts(s) {for(i=0;i<numoflns;i++)  \
                     { MoveTo((int)vertex[s][line[i].v1].x,  \
                       (int)vertex[s][line[i].v1].y); \
                       LineTo((int)vertex[s][line[i].v2].x, \
                       (int)vertex[s][line[i].v2].y); }}  
 
#define numofpts 8 /* A cube has eight vertices */
#define numoflns 12    /* lines for every face. */

/* the following are the data structs for vertices and lines*/ typedef 
struct rec1 {float x,y,z;} point3d;
typedef struct rec2 {int v1,v2;} edge;
void mult();/* Matrices multiplication */

main()
{
  point3d vertex[2][8], /* array of 3D pts   */
          center;/* centroid of cube */
  edge    line[12];/* array of lines */
  int     buttondown=0, /* mousedwn flag(for prog end)*/
          keypressed=0,       /* keydwn flg(for arrows)     */
          flip=0,             /* This is index for vertex so*/
          flop=1,             /* can undraw flip & draw flop*/
          i,                  /* counter           */
          rot=0; /* Flag for direction of rotat*/
  long    low;   /* low word of keydwn message */
  float   a,/* Particular angle of rotat     */
          R[4][4], /* Rotation matrix*/
          c[4][4], /* Product of trans & rot mats*/
          d[4][4], /* Product of c and inv trans */
          T[4][4],Tinv[4][4], /* Translation & inv trans    */
          x=0.087266;/* Algle of rot in rad  */
  EventRecord nextevent;
  KeyMap    thekeys;
  WindowPtr scnwdw;
  Rect      scnrect;
/*********************************************
*  Set things up *
*********************************************/
InitGraf(&thePort);
InitFonts();
FlushEvents(everyEvent,0);
InitWindows();
InitMenus();
TEInit();
InitDialogs(0);
InitCursor();
scnrect=screenBits.bounds;
InsetRect(&scnrect,50,50);
scnwdw=NewWindow(0,&scnrect,”\p”,TRUE,dBoxProc,-1,FALSE,0);
  
/*********************************************
*  Get points. Arbitrary cube.*
*********************************************/
center.x=300;center.y=200;center.z=120;
vertex[0][0].x=280;vertex[0][0].y=220;vertex[0][0].z=100;
vertex[0][1].x=320;vertex[0][1].y=220;vertex[0][1].z=100;
vertex[0][2].x=320;vertex[0][2].y=180;vertex[0][2].z=100;
vertex[0][3].x=280;vertex[0][3].y=180;vertex[0][3].z=100;
vertex[0][4].x=280;vertex[0][4].y=220;vertex[0][4].z=140;
vertex[0][5].x=320;vertex[0][5].y=220;vertex[0][5].z=140;
vertex[0][6].x=320;vertex[0][6].y=180;vertex[0][6].z=140;
vertex[0][7].x=280;vertex[0][7].y=180;vertex[0][7].z=140;
line[0].v1=0;line[0].v2=1;
line[1].v1=1;line[1].v2=2;
line[2].v1=2;line[2].v2=3;
line[3].v1=3;line[3].v2=0;
line[4].v1=0;line[4].v2=4;
line[5].v1=1;line[5].v2=5;
line[6].v1=2;line[6].v2=6;
line[7].v1=3;line[7].v2=7;
line[8].v1=4;line[8].v2=5;
line[9].v1=5;line[9].v2=6;
line[10].v1=6;line[10].v2=7;
line[11].v1=7;line[11].v2=4;
T[0][0]=1;T[0][1]=0;T[0][2]=0;T[0][3]=0;
T[1][0]=0;T[1][1]=1;T[1][2]=0;T[1][3]=0;
T[2][0]=0;T[2][1]=0;T[2][2]=1;T[2][3]=0;
T[3][0]=-center.x;T[3][1]=-center.y;T[3][2]=-center.z;T[3][3]=1;
Tinv[0][0]=1;Tinv[0][1]=0;Tinv[0][2]=0;Tinv[0][3]=0;
Tinv[1][0]=0;Tinv[1][1]=1;Tinv[1][2]=0;Tinv[1][3]=0;
Tinv[2][0]=0;Tinv[2][1]=0;Tinv[2][2]=1;Tinv[2][3]=0;
Tinv[3][0]=center.x;Tinv[3][1]=center.y;Tinv[3][2]=center.z;Tinv[3][3]=1;

/*********************************************
*  Rotate *
*********************************************/
viewpts(flip);   /* This draws first set of pts*/
  while(!buttondown) /* Mini event loop*/
  {
    keypressed=0;
    SystemTask();
    if(GetNextEvent(-1,&nextevent))
      if(nextevent.what==mouseDown) buttondown=1;
      else if(nextevent.what==keyDown) keypressed=1;
      else if(nextevent.what==autoKey) keypressed=1;
    if(keypressed) /* Find out which one     */
    {
      keypressed=0;
      low=LoWord(nextevent.message);
      low=BitShift(low,-8);
      if(low==126) {rot=1;a=-x;} /* Set dir flag and-*/
      if(low==124) {rot=2;a=-x;} /* angle(pos or neg */
      if(low==125) {rot=3;a=x;}
      if(low==123) {rot=4;a=x;}
      switch(rot)
      {
        case 1:/* Both of these are rot about the X axis */
        case 3: R[0][0]=1;R[0][1]=0;R[0][2]=0;R[0][3]=0;
 R[1][0]=0;R[1][1]=cos(a);R[1][2]=sin(a);R[1][3]=0;
 R[2][0]=0;R[2][1]=-sin(a);R[2][2]=cos(a);R[2][3]=0;
 R[3][0]=0;R[3][1]=0;R[3][2]=0;R[3][3]=1;break;
        case 2:/* Both of these are rot about the Y axis */
        case 4: 
 R[0][0]=cos(a);
 R[0][1]=0;R[0][2]=-sin(a);R[0][3]=0;
       R[1][0]=0;R[1][1]=1;R[1][2]=0;R[1][3]=0;
       R[2][0]=sin(a);R[2][1]=0;R[2][2]=cos(a);R[2][3]=0;
       R[3][0]=0;R[3][1]=0;R[3][2]=0;R[3][3]=1;break;
      }  /*end switch*/
      mult(T,R,c); /* Combine trans & rotation */
      mult(c,Tinv,d);/* Combine that and inv trans */
      flip++;flip=flip%2;flop++;flop=flop%2; /* flip flop   */
      /* The following actually calculates new vert of rotat*/
      for(i=0;i<numofpts;i++)
      {
        vertex[flip][i].x=vertex[flop][i].x*d[0][0]
                    +vertex[flop][i].y*d[1][0]
                    +vertex[flop][i].z*d[2][0]
                    +1*d[3][0];
        vertex[flip][i].y=vertex[flop][i].x*d[0][1]
                    +vertex[flop][i].y*d[1][1]
                    +vertex[flop][i].z*d[2][1]
                    +1*d[3][1];
        vertex[flip][i].z=vertex[flop][i].x*d[0][2]
                    +vertex[flop][i].y*d[1][2]
                    +vertex[flop][i].z*d[2][2]
                    +1*d[3][2];
       }
       ForeColor(whiteColor);
       viewpts(flop);/* Undraw*/
       ForeColor(blackColor);
       viewpts(flip);/* Draw*/
    }  /*end update points*/
  }

/*********************************************
*  End everything*
*********************************************/
DisposeWindow(scnwdw);
}  /*program end*/

void mult(A,B,C)
  float A[][4],B[][4],C[][4];
{
  int i,j,k;
  
  for(i=0;i<=3;i++)
    for(j=0;j<=3;j++)
    {
      C[i][j]=0.0;
      for(k=0;k<=3;k++)
        C[i][j]+=A[i][k]*B[k][j];
    }
}  /*end mult*/

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

OmniPlan Pro 3.6 - Professional-grade pr...
With OmniPlan Pro, you can create logical, manageable project plans with Gantt charts, schedules, summaries, milestones, and critical paths. Break down the tasks needed to make your project a success... Read more
Little Snitch 3.7.1 - Alerts you about o...
Little Snitch gives you control over your private outgoing data. Track background activity As soon as your computer connects to the Internet, applications often have permission to send any... Read more
iMazing 2.1.3 - Complete iOS device mana...
iMazing (was DiskAid) is the ultimate iOS device manager with capabilities far beyond what iTunes offers. With iMazing and your iOS device (iPhone, iPad, or iPod), you can: Copy music to and from... Read more
AppDelete 4.3.1 - $7.99
AppDelete is an uninstaller that will remove not only applications but also widgets, preference panes, plugins, and screensavers along with their associated files. Without AppDelete these associated... Read more
FileZilla 3.23.0.2 - Fast and reliable F...
FileZilla (ported from Windows) is a fast and reliable FTP client and server with lots of useful features and an intuitive interface. Version 3.23.0.2: Bug Fixes and Minor Changes Speed up icon... Read more
PDFpen 8.3 - $74.95
PDFpen allows users to easily edit PDF's. Add text, images and signatures. Fill out PDF forms. Merge or split PDF documents. Reorder and delete pages. Even correct text and edit graphics! Features... Read more
TunnelBear 3.0.8 - Subscription-based pr...
TunnelBear is a subscription-based virtual private network (VPN) service and companion app, enabling you to browse the internet privately and securely. Features Browse privately - Secure your data... Read more
Safari Technology Preview 10.1 - The new...
Safari Technology Preview contains the most recent additions and improvements to WebKit and the latest advances in Safari web technologies. And once installed, you will receive notifications of... Read more
Ableton Live 9.7.1 - Record music using...
Ableton Live lets you create and record music on your Mac. Use digital instruments, pre-recorded sounds, and sampled loops to arrange, produce, and perform your music like never before. Ableton Live... Read more
BetterTouchTool 1.963 - Customize Multi-...
BetterTouchTool adds many new, fully customizable gestures to the Magic Mouse, Multi-Touch MacBook trackpad, and Magic Trackpad. These gestures are customizable: Magic Mouse: Pinch in / out (zoom... Read more

Latest Forum Discussions

See All

Bully: Anniversary Edition (Games)
Bully: Anniversary Edition 1.03.1 Device: iOS Universal Category: Games Price: $6.99, Version: 1.03.1 (iTunes) Description: *** PLEASE NOTE: This game is officially supported on the following devices: iPhone 5 and newer, iPod Touch... | Read more »
PINE GROVE (Games)
PINE GROVE 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: A pine grove where there are no footsteps of people due to continuous missing cases. The case is still unsolved and nothing has... | Read more »
Niantic teases new Pokémon announcement...
After rumors started swirling yesterday, it turns out there is an official Pokémon GO update on its way. We’ll find out what’s in store for us and our growing Pokémon collections tomorrow during the Starbucks event, but Niantic will be revealing... | Read more »
3 reasons why Nicki Minaj: The Empire is...
Nicki Minaj is as business-savvy as she is musically talented and she’s proved that by launching her own game. Designed by Glu, purveyors of other fine celebrity games like cult favorite Kim Kardashian: Hollywood, Nicki Minaj: The Empire launched... | Read more »
Clash of Clans is getting its own animat...
Riding on its unending wave of fame and success, Clash of Clans is getting an animated web series based on its Clash-A-Rama animated shorts.As opposed to the current shorts' 60 second run time, the new and improved Clash-A-Rama will be comprised of... | Read more »
Leaks hint at Pokémon GO and Starbucks C...
Leaked images from a hub for Starbucks employees suggests that a big Pokémon GO event with the coffee giant could begin this very week. The images appeared on Reddit and hint at some exciting new things to come for Niantic's smash hit game. | Read more »
Silent Depth Submarine Simulation (Game...
Silent Depth Submarine Simulation 1.0 Device: iOS Universal Category: Games Price: $7.99, Version: 1.0 (iTunes) Description: | Read more »
Enneas Saga lets you lead your own demon...
Defend the land of Enneas Continent from the forces of evil in the new fantasy MMORPG from Lyto Mobi: Enneas Saga. Can’t wait? No problem. It’s available to download now on Android devices. | Read more »
Great zombie games in the spirit of Dead...
Dead Rising 4 arrives tomorrow, giving enthusiasts a fresh chance to take selfies with zombies and get up to other ridiculous end-of-the-world shenanigans. To really get into the spirit of things, we've gone and gathered the best zombie games that... | Read more »
Amateur Surgeon 4 Guide: Advanced tips a...
Amateur Surgeon 4 is still tackling the competition at the top of the App Store charts, so if you haven't tried it out yet, you should probably do that right away. If you've been at it for a while, though, perhaps you're ready to start expanding... | Read more »

Price Scanner via MacPrices.net

Holiday sale: 12-inch Retina MacBook for $100...
B&H has 12″ Retina MacBooks on sale for $100 off MSRP as part of their Holiday sale. Shipping is free, and B&H charges NY sales tax only: - 12″ 1.1GHz Space Gray Retina MacBook: $1199 $100... Read more
Apple refurbished 13-inch MacBook Airs availa...
Apple has Certified Refurbished 13″ MacBook Airs available starting at $849. An Apple one-year warranty is included with each MacBook, and shipping is free: - 13″ 1.6GHz/8GB/128GB MacBook Air: $849 $... Read more
Apple refurbished iMacs available for up to $...
Apple has Certified Refurbished 2015 21″ & 27″ iMacs available for up to $350 off MSRP. Apple’s one-year warranty is standard, and shipping is free. The following models are available: - 21″ 3.... Read more
Apple’s Education discount saves up to $300 o...
Purchase a new Mac or iPad using Apple’s Education Store and take up to $300 off MSRP. All teachers, students, and staff of any educational institution qualify for the discount. Shipping is free: -... Read more
Back in stock: Apple refurbished Mac minis fr...
Apple has Certified Refurbished Mac minis available starting at $419. Apple’s one-year warranty is included with each mini, and shipping is free: - 1.4GHz Mac mini: $419 $80 off MSRP - 2.6GHz Mac... Read more
Twenty-Five Years Of Apple Laptops – A person...
Among many other things, the often tumultuous 16th year of the new century marked the 25th anniversary of Apple laptop computers, not counting the optimistically named 16-pound Mac Portable of 1989.... Read more
Landlordy iOS App Adds Support For Appliances...
Riga, Latvia based E-protect SIA is releasing major update (version 1.8) to its Landlordy app for managing rental business financials on the go. Landlordy is iPhone and iPad app designed for self-... Read more
Holiday sale, Apple iMacs for up to $200 off...
B&H Photo has 21″ and 27″ Apple iMacs on sale for up to $200 off MSRP including free shipping plus NY sales tax only: - 27″ 3.3GHz iMac 5K: $2099 $200 off MSRP - 27″ 3.2GHz/1TB Fusion iMac 5K: $... Read more
Holiday sale: Mac minis for $50 to $100 off M...
B&H Photo has Mac minis on sale for up to $100 off MSRP free shipping plus NY sales tax only: - 1.4GHz Mac mini: $449 $50 off MSRP - 2.6GHz Mac mini: $629 $70 off MSRP - 2.8GHz Mac mini: $899 $... Read more
Mac Pros on sale for up to $300 off MSRP, ref...
B&H Photo has Mac Pros on sale for up to $300 off MSRP. Shipping is free, and B&H charges sales tax in NY only: - 3.7GHz 4-core Mac Pro: $2799, $200 off MSRP - 3.5GHz 6-core Mac Pro: $3699, $... Read more

Jobs Board

*Apple* Retail - Multiple Positions- Philade...
Job Description: Sales Specialist - Retail Customer Service and Sales Transform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Retail - Multiple Positions- San Ant...
Job Description:SalesSpecialist - Retail Customer Service and SalesTransform Apple Store visitors into loyal Apple customers. When customers enter the store, Read more
*Apple* Products Tester Needed - Apple (Unit...
…we therefore look forward to put out products to quality test for durability. Apple leads the digital music revolution with its iPods and iTunes online store, Read more
SW Engineer *Apple* TV Frameworks - Apple I...
The Apple TV team is looking for a software...create features that reflect the look and feel of Apple TV. Description: Were looking for someone who is Read more
Hardware Design Validation Engineer - *Apple...
The Apple Watch team is looking for a Hardware Design Validation Engineer. This person will be part of the Apple Watch hardware team with responsibilities for Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.