REVOLVE.C

/*-----------------------------------------
   REVOLVE.C -- Demonstrates GPI Transforms
  -----------------------------------------*/

#define INCL_WIN
#define INCL_GPI

#include <os2.h>
#include <math.h>
#include <stddef.h>

MRESULT EXPENTRY ClientWndProc (HWND, USHORT, MPARAM, MPARAM) ;

HAB hab ;

int main (void)
     {
     static CHAR szClientClass [] = "Revolve" ;
     HMQ    hmq ;
     HWND   hwndFrame, hwndClient ;
     QMSG   qmsg ;
     static ULONG flFrameFlags = FCF_TITLEBAR      | FCF_SYSMENU |
                                 FCF_SIZEBORDER    | FCF_MINMAX  |
                                 FCF_SHELLPOSITION | FCF_TASKLIST ;

     hab = WinInitialize (0) ;
     hmq = WinCreateMsgQueue (hab, 0) ;

     WinRegisterClass (hab, (PCSZ) szClientClass, (PFNWP) ClientWndProc, CS_SIZEREDRAW |
                                                          CS_SYNCPAINT, 0) ;

     hwndFrame = WinCreateStdWindow (HWND_DESKTOP, WS_VISIBLE,
                    &flFrameFlags,
                    (PCSZ) szClientClass, (PCSZ) " GPI Transform Demo",
                    0L, 0, 0, &hwndClient) ;

     while (WinGetMsg (hab, &qmsg, 0, 0, 0) )
          WinDispatchMsg (hab, &qmsg) ;

     WinDestroyWindow (hwndFrame) ;
     WinDestroyMsgQueue (hmq) ;
     WinTerminate (hab) ;

     return 0 ;
     }

VOID SetModelTransform (HPS hps, FIXED fxYscale, FIXED fxAngle,
                                                 FIXED fxScale)
     {
     MATRIXLF matlf ;

     GpiSetModelTransformMatrix (hps, 0L, NULL, TRANSFORM_REPLACE) ;
     GpiQueryModelTransformMatrix (hps, 9L, &matlf) ;

     matlf.fxM22 = fxYscale ;

     GpiSetModelTransformMatrix (hps, 9L, &matlf, TRANSFORM_REPLACE) ;

     matlf.fxM11 = (FIXED) (cos (6.283*fxAngle/65536/360) * 65536) ;
     matlf.fxM22 = matlf.fxM11 ;
     matlf.fxM12 = (FIXED) (sin (6.283*fxAngle/65536/360) * 65536) ;
     matlf.fxM21 = -matlf.fxM12 ;

     GpiSetModelTransformMatrix (hps, 9L, &matlf, TRANSFORM_ADD) ;

     matlf.fxM11 = matlf.fxM22 = fxScale ;
     matlf.fxM12 = matlf.fxM21 = 0 ;

     GpiSetModelTransformMatrix (hps, 9L, &matlf, TRANSFORM_ADD) ;
     }

VOID DrawFigure (HPS hps)
     {
     static POINTL aptlFigure [] =
               {
                {-20,  100},  {20,  100},  {20,   90},   {10,   90},   {10,   85},
                 {20,   85},  {20,   75},  {35,   75},   {35,   70},   {20,   70},
                 {20,   65},   {5,   65},   {5,   60},   {20,   60},   {10,   50},
                 {10,   40},  {25,   40},  {85,  100},  {100,  100},  {100,   85},
                 {25,   10},  {25,  -25},  {50,  -85},   {75,  -85},   {75, -100},
                 {35, -100},   {0,  -15}, {-35, -100},  {-75, -100},  {-75,  -85},
                {-50,  -85}, {-25,  -25}, {-25,   10},  {-85,  -50}, {-100,  -50},
               {-100,  -35}, {-25,   40}, {-10,   40},  {-10,   50},  {-20,   60},
                {-20,  100}
               } ;

     GpiMove (hps, aptlFigure) ;

     GpiPolyLine (hps, sizeof aptlFigure / sizeof aptlFigure [0] - 1L,
                  aptlFigure + 1) ;
     }

MRESULT EXPENTRY ClientWndProc (HWND hwnd, USHORT msg, MPARAM mp1,
                                                       MPARAM mp2)
     {
     static double dScaler = 1.1, dYScaleAngle = 0.0,
                   dYScaleAngleInc = 0.25 ;
     static FIXED  fxAngle, fxAngleInc = 0xA0000L,
                   fxYScale, fxScale = 0x2000L ;
     static HPS    hps ;
     HDC           hdc ;
     MATRIXLF      matlf ;
     POINTL        ptl ;
     SIZEL         sizl ;

     switch (msg)
          {
          case WM_CREATE:
               hdc = WinOpenWindowDC (hwnd) ;

               sizl.cx = sizl.cy = 0 ;

               hps = GpiCreatePS (hab, hdc, &sizl, PU_LOENGLISH |
                                    GPIF_DEFAULT | GPIT_MICRO   |
                                    GPIT_NORMAL  | GPIA_ASSOC) ;

               GpiSetMix (hps, FM_INVERT) ;

               if (!WinStartTimer (hab, hwnd, 1, 100L))
                    WinAlarm (HWND_DESKTOP, WA_ERROR) ;

               break ;
          case WM_SIZE:
               ptl.x = LOUSHORT (mp2) / 2 ;  // Half of window width
               ptl.y = HIUSHORT (mp2) / 2 ;  // Half of window height

               GpiConvert (hps, CVTC_DEVICE, CVTC_PAGE, 1L, &ptl) ;

               GpiQueryDefaultViewMatrix (hps, 9L, &matlf) ;

               matlf.lM31 = ptl.x ;
               matlf.lM32 = ptl.y ;

               GpiSetDefaultViewMatrix (hps, 9L, &matlf,
                                             TRANSFORM_REPLACE) ;
               break ;

          case WM_TIMER:
               SetModelTransform (hps, fxYScale, fxAngle, fxScale) ;
               DrawFigure (hps) ;

               fxYScale = (FIXED) (65535 * cos (dYScaleAngle)) ;

               if ((dYScaleAngle += dYScaleAngleInc) > 6.283)
                    dYScaleAngle -= 6.283 ;

               if ((fxAngle += fxAngleInc) > (FIXED) 0x16800000L)
                    fxAngle -= (FIXED) 0x16800000L ;

               if ((FIXED) (fxScale *= dScaler) >= (FIXED) 0x30000L ||
                         fxScale <= (FIXED) 0x2000L)
                    dScaler = 1 / dScaler ;

               SetModelTransform (hps, fxYScale, fxAngle, fxScale) ;
               DrawFigure (hps) ;
               break ;

          case WM_PAINT:
               WinBeginPaint (hwnd, hps, NULL) ;

               GpiErase (hps) ;

               SetModelTransform (hps, fxYScale, fxAngle, fxScale) ;
               DrawFigure (hps) ;

               WinEndPaint (hps) ;
               break ;

          case WM_DESTROY:
               WinStopTimer (hab, hwnd, 1) ;
               GpiDestroyPS (hps) ;
               break ;

          default:
               return WinDefWindowProc (hwnd, msg, mp1, mp2) ;
          }
     return 0 ;
     }