Fresh Fish 9/FreshFishVol9-CD2.bin/bbs/gfx/imagefx_sdk-2.0.lha/ImageFX_SDK/sas/examples/hooks/sample3.c

C/C++ Source or Header | 1995-02-15 | 4.9 KB | 170 lines

/*
 * Sample3
 *
 * This sample demonstrates some of the newer features in ImageFX.
 * It shows the recommended way to handle Arexx arguments, remember
 * GUI settings,
 *
 * This hook does a simple blur.
 *
 * Written by Thomas Krehbiel, 15-Jan-95
 *
 */

#include <scan/hooks.h>
#include <scan/procinfo.h>
#include <clib/dos_protos.h>
#include <clib/intuition_protos.h>
#include <clib/graphics_protos.h>


/* This information is required by the "start.o" startup code. */
char *HookName = "Sample3";

/* A version string so the Version command works on us. */
char *HookVersion = "\0$VER: Sample3 2.0.6 (15.2.95)";


/*******************************************************************
 *
 *  Defines
 *
 *******************************************************************/

#define MIN(a,b)     ((a) < (b) ? (a) : (b))


/*******************************************************************
 *
 *  Text Array and Indexes
 *
 *******************************************************************/

/* This information is required by the "start.o" startup code. */
/* For this example, we're not doing any localization stuff. */

char *HookText = "Hook_Sample3";
int   HookTextCount = 0;
char **HookStrings[] = { NULL };


/*******************************************************************
 *
 *  Support functions
 *
 *******************************************************************/

static void __inline do_blur (UBYTE *src, UBYTE *dst, LONG n, LONG bytes, LONG center)
{
   register LONG total;
   register LONG bytes2 = bytes * 2;

   while (n--)
   {

      total = *(src-1)        + *(src)                + *(src+1)       +
              *(src+bytes-1)  + *(src+bytes) * center + *(src+bytes+1) +
              *(src+bytes2-1) + *(src+bytes2)         + *(src+bytes2+1);

      *dst++ = total / (8 + center);
      src++;

   }
}

/*******************************************************************
 *
 *  Hook entry point is here.
 *
 *******************************************************************/

void hook_main (int argc, char **argv)
{
   struct Buffer *buf;
   struct ProcessInfo *pi;
   LONG argarray[8] = { 0 };
   APTR as;
   int amount;
   int j;
   BOOL success = FALSE;

   // ObtainCurrentBuffer() returns a pointer to the buffer we should
   // work on.  This could be either the main buffer or the current
   // brush, depending on the Region setting.

   if (!(buf = ObtainCurrentBuffer()))
      hook_exit(20);

   if (argc > 1)
   {
      // arexx arguments were provided.  We use the ReadArgv() function
      // found in scan.lib to parse the arguments.  ReadArgv() performs
      // almost the same function as ReadArgs() in dos.library.  The
      // format of the results in argarray[] are the same as ReadArgs().

      if (as = ReadArgv(argc, argv, "Amount/N", argarray))
      {
         amount = *((LONG *)argarray[0]);
         FreeArgv(as);
      }
   }
   else
   {
      // no arexx arguments provided.  Show our interface.  We use
      // GetIfxVar() in scan.lib to find out what the last value the
      // user entered into this requester was.

      amount = GetIfxVar("HookBlurAmount", 8);
      amount = IntegerRequest("Enter blur amount:", 1, 16, amount);
      if (amount < 1)
      {
         SetError(ERR_UserCancel);
         hook_exit(20);
      }

      // save this setting with SetIfxVar() for the next time we run
      // this hook.
      SetIfxVar("HookBlurAmount", amount);
   }

   amount = 17 - amount;      // reverse logic of amount

   // This example uses the PrepareProcess()/FinishProcess() function
   // calls to process the image.  The PFF_UNDO flag tells PrepareProcess()
   // to save an undo buffer before proceeding.  Using these functions
   // ensures that your hook will handle feathering, regions, include/exclude,
   // channel masks, virtual memory, and any other miscellaneous settings
   // properly.

   if (pi = PrepareProcess("Sample3", buf, 3, 3, PPF_UNDO))
   {
      for (j = 0; j < pi->Height; j++)
      {
         if (!(success = GetData(pi, j - 1, 3, 0))) break;
         do_blur(pi->SR, pi->TR, pi->Width, pi->Bytes, amount);
         if (buf->Depth > 1)
         {
            do_blur(pi->SG, pi->TG, pi->Width, pi->Bytes, amount);
            do_blur(pi->SB, pi->TB, pi->Width, pi->Bytes, amount);
         }
         if (!(success = PutData(pi, j, 1, 0))) break;
      }
      FinishProcess(pi);

      // if successful, we should call the scan.library Learn() function
      // to record the settings necessary to duplicate what was just
      // done.  This is recorded into a learn file if this feature is
      // enabled by the user.
      if (success) Learn("Hook Sample3 %ld", 17 - amount);
   }

   // if successful, redraw what was modified
   if (success)
      RedrawCurrent();

   // ImageFX checks the error value after the hook is finished.  If it
   // is non-zero, ImageFX displays an error requester corresponding
   // to the error value returned.  Otherwise, no requester is shown.
   SetError(0);
}