path: root/tkagif/tkagif.C

// Copyright (C) 1999-2015
// Smithsonian Astrophysical Observatory, Cambridge, MA, USA
// For conditions of distribution and use, see copyright notice in "copyright"

#include <iostream>
#include <sstream>
#include <fstream>
using namespace std;

#include <string.h>
#include <tk.h>

#include "tkagif.h"

extern "C" {
  int Tkagif_Init(Tcl_Interp* interp);
  int TkagifCmd(ClientData data, Tcl_Interp *interp, int argc, 
	       const char* argv[]);
}

TkAGIF* tkagif=NULL;

int Tkagif_Init(Tcl_Interp* interp) {

  if (Tcl_InitStubs(interp, TCL_PATCH_LEVEL, 0) == NULL)
    return TCL_ERROR;

  if (Tk_InitStubs(interp, TK_PATCH_LEVEL, 0) == NULL)
    return TCL_ERROR;

  Tcl_CreateCommand(interp, "agif", TkagifCmd,
		    (ClientData)NULL, (Tcl_CmdDeleteProc *)NULL);

  if (Tcl_PkgProvide(interp, PACKAGE_NAME, PACKAGE_VERSION) != TCL_OK)
    return TCL_ERROR;

  tkagif = new TkAGIF(interp);

  if (tkagif)
    return TCL_OK;
  else
    return TCL_ERROR;
}

int TkagifCmd(ClientData data,Tcl_Interp *interp,int argc,const char* argv[])
{
  if (argc>=2) {
    if (!strncmp(argv[1], "create", 3))
      return tkagif->create(argc, argv);
    else if (!strncmp(argv[1], "colortable", 3))
      return tkagif->colortable(argc, argv);
    else if (!strncmp(argv[1], "add", 3))
      return tkagif->add(argc, argv);
    else if (!strncmp(argv[1], "close", 3))
      return tkagif->close(argc, argv);
    else {
      Tcl_AppendResult(interp, "tkagif: unknown command: ", argv[1], NULL);
      return TCL_ERROR;
    }
  }
  else {
    Tcl_AppendResult(interp, "usage: tkagif ?create?colortable?add?close?",  NULL);
    return TCL_ERROR;
  }
}

TkAGIF::TkAGIF(Tcl_Interp* interp)
{
  interp_ = interp;
  out_ =NULL;
  width_ = height_ = 512;
  colorTableType_ = GREY;
}

int TkAGIF::create(int argc, const char* argv[])
{
  if (argc == 5) {
    if (*argv[2] == '\0') {
      Tcl_AppendResult(interp_, "bad filename", NULL);
      return TCL_ERROR;
    }
  }
  else {
    Tcl_AppendResult(interp_, "usage: tkagif create <filename>", NULL);
    return TCL_ERROR;
  }

  // open fn
  out_ = new ofstream(argv[2]);
  if (!out_) {
    Tcl_AppendResult(interp_, "Error: unable to open filename ", NULL);
    if (*argv[2])
      Tcl_AppendResult(interp_, argv[2], NULL);
    return TCL_ERROR;
  }

  {
    string s(argv[3]);
    istringstream str(s);
    str >> width_;
  }
  {
    string s(argv[4]);
    istringstream str(s);
    str >> height_;
  }

  // *** Header ***
  {
    char header[] = "GIF89a";
    out_->write(header,6);
  }
  
  // *** Logical Screen Descriptor ***
  {
    // width
    unsigned short ww = width_;
    out_->write((char*)&ww,2);
    // height
    unsigned short hh = height_;
    out_->write((char*)&hh,2);

    // Packed Field: msb to lsb
    // global color table flag (1): 0 no gct, 1: gct
    // color resolution (3): number bits-1
    // sort flag (1): 0 not ordered, 1 ordered decreasing importance
    // size of global color table (3): size 2^(x+1)
    char pkg=0xF7;
    out_->write(&pkg,1);

    // BG Color
    char bg=0x00;
    out_->write(&bg,1);

    // Pixel Aspect Ratio
    char ar=0x00;
    out_->write(&ar,1);
  }
  
  return TCL_OK;
}

int TkAGIF::colortable(int argc, const char* argv[])
{
  if (argc == 3) {
    if (!strncmp(argv[2],"grey",3))
      colorTableType_ = GREY;
    else if (!strncmp(argv[2],"red",3))
      colorTableType_ = RED;
    else if (!strncmp(argv[2],"green",3))
      colorTableType_ = GREEN;
    else if (!strncmp(argv[2],"blue",3))
      colorTableType_ = BLUE;
    else if (!strncmp(argv[2],"pseudo",3))
      colorTableType_ = PSEUDO;
    else if (!strncmp(argv[2],"rgb",3))
      colorTableType_ = RGB;
    else {
      Tcl_AppendResult(interp_, "bad colortable option", NULL);
      return TCL_ERROR;
    }
  }
  else {
    Tcl_AppendResult(interp_, "usage: tkagif colortable grey|red|green|blue|pseudo}rgb", NULL);
    return TCL_ERROR;
  }

  // colortable
  unsigned char red[256];
  unsigned char green[256];
  unsigned char blue[256];
  memset(red,0,256);
  memset(green,0,256);
  memset(blue,0,256);
  
  switch (colorTableType_) {
  case GREY:
    for(int ii=0; ii<256; ii++)
      red[ii] = green[ii] = blue[ii] = ii;
    break;
  case RED:
    for(int ii=0; ii<256; ii++)
      red[ii] = ii;
    break;
  case GREEN:
    for(int ii=0; ii<256; ii++)
      green[ii] = ii;
    break;
  case BLUE:
    for(int ii=0; ii<256; ii++)
      blue[ii] = ii;
    break;
  case PSEUDO:
    break;
  case RGB:
    for (int rr=0, ii=0; rr<8; rr++) {
      for (int gg=0; gg<8; gg++) {
	for (int bb=0; bb<8; bb++) {
	  red[ii] = rr*32;
	  green[ii] = gg*32;
	  blue[ii] = bb*32;
	  ii++;
	}
      }
    }
    red[255] = 0xFF;
    green[255] = 0xFF;
    blue[255] = 0xFF;
    break;
  }
      
  // *** Global Color Table ***
  for (int ii=0; ii<256; ii++) {
    out_->write((char*)red+ii,1);
    out_->write((char*)green+ii,1);
    out_->write((char*)blue+ii,1);
  }

  // *** Application Extension Block ***
  {
    // Extention Introducer
    char ext = 0x21;
    out_->write(&ext,1);
    // Extention Lable
    char lable = 0xFF;
    out_->write(&lable,1);
    // Block Size
    char ss= 0x0B;
    out_->write(&ss,1);
    // Applcation Identifier
    char id[] = "NETSCAPE";
    out_->write(id,8);
    // Authentication Code
    char code[] = "2.0";
    out_->write(code,3);
    // Application Data Size
    char dd=0x03;
    out_->write(&dd,1);
    // Application Data
    char rep[] = {0x01,0x00,0x00};
    out_->write(rep,3);
    // Block Terminator
    char end=0x00;
    out_->write(&end,1);
  }
  
  return TCL_OK;
}

int TkAGIF::add(int argc, const char* argv[])
{
  if (argc == 3) {
    if (*argv[2] == '\0') {
	Tcl_AppendResult(interp_, "bad filename", NULL);
	return TCL_ERROR;
    }
  }
  else {
    Tcl_AppendResult(interp_, "usage: tkagif add <image>", NULL);
    return TCL_ERROR;
  }

  Tk_PhotoHandle photo = Tk_FindPhoto(interp_, argv[2]);
  if (!photo) {
    Tcl_AppendResult(interp_, "bad image handle", NULL);
    return TCL_ERROR;
  }
  Tk_PhotoImageBlock block;
  if (!Tk_PhotoGetImage(photo,&block)) {
    Tcl_AppendResult(interp_, "bad image block", NULL);
    return TCL_ERROR;
  }

  // *** Graphic Control Extension ***
  {
    // Extention Introducer
    char ext = 0x21;
    out_->write(&ext,1);
    // Extention Lable
    char lable = 0xF9;
    out_->write(&lable,1);
    // Block Size
    char ss= 0x04;
    out_->write(&ss,1);
    // Packed Field msb to lsb
    // Reserved (3)
    // Displosal Method (3): 0 none, 1 do not dispose, 2 restore bg, 3 restore
    // User Input Flag (1): 0 none, 1 expected
    // Transparent Color Flag (1): 0 not given, 1 color index
    char pkg= 0x00;
    out_->write(&pkg,1);
    // Delay Time
    unsigned short delay = 0x00;
    out_->write((char*)&delay,2);
    // Transparent Color Index
    char trans= 0x00;
    out_->write(&trans,1);
    // Block Terminator
    char end= 0x00;
    out_->write(&end,1);
  }
  
  // *** Local Image Descriptor ***
  {
    // Image Separator
    char img= 0x2C;
    out_->write(&img,1);

    // Image Left Position
    unsigned short left = 0;
    out_->write((char*)&left,2);

    // Image Top Position
    unsigned short top = 0;
    out_->write((char*)&top,2);

    // Image Width
    unsigned short ww = width_;
    out_->write((char*)&ww,2);

    // Image Heght
    unsigned short hh = height_;
    out_->write((char*)&hh,2);

    // Packed Field msb to lsb
    // Local Table Flag (1): 1 local table, 0 no
    // Interlace Flag (1): 1 interlaced, 0 no
    // Sort Flag (1): 1 sorted, 0 no
    // Reserved (2):
    // Size of Local Table (3)
    char pkg= 0x00;
    out_->write(&pkg,1);
  }
  
  // *** Local Color Table ***
  // not present

  // *** Image Data ***
  {
    // LZW Min Code Size
    char lzw = 0x08;
    out_->write(&lzw,1);

    // Data
    for (int jj=0; jj<height_; jj++) {
      int ii =0;
      while (ii<width_) {
	char clear = 0x80;
	out_->write(&clear,1);
	int ww = width_-ii;
	int ll = ww < 0x2E ? ww : 0x2E;
	char ss= ll+1;
	out_->write(&ss,1);
	for (unsigned char kk=0; kk<ll; kk++) {
	  char pix = rand() % 200;
	  out_->write(&pix,1);
	  ii++;
	}
      }
    }
    char stop[] = {0x01,0x81};
    out_->write(stop,2);
    char end= 0x00;
    out_->write(&end,1);
  }
  
  return TCL_OK;
}

int TkAGIF::close(int argc, const char* argv[])
{
  // *** Trailer ***
  char end = 0x3B;
  out_->write(&end,1);

  out_->close();
  delete out_;
  
  return TCL_OK;
}