#include <Inventor/SoOffscreenRenderer.h>
#include <Inventor/nodes/SoCamera.h>
#include <Inventor/nodes/SoMaterial.h>
#include <Inventor/nodes/SoDirectionalLight.h>
#include <Inventor/nodes/SoGroup.h>
#include <Inventor/nodes/SoLightModel.h>
#include <Inventor/nodes/SoSelection.h>
#include <Inventor/nodes/SoSeparator.h>
#include <Inventor/actions/SoWriteAction.h>
#include <Inventor/SbViewportRegion.h>
#include <Inventor/Xt/SoXt.h>
#include <Inventor/Xt/viewers/SoXtExaminerViewer.h>

#include <X11/Intrinsic.h>
#include <Xm/Xm.h>

#include <stdio.h>

extern void Cancel_CB(Widget, XtPointer, XtPointer);
extern SoXtExaminerViewer *myViewer;
extern SoSeparator *root;
extern SoMaterial *BGMaterial;

// Hardcoded printer dpi ( as variable dpi ).
int PixPerInch = 150;

void
WriteEPS( Widget menu_item , XtPointer, XtPointer call_data )
{
  char *file;
  int dpi = PixPerInch;
  FILE *fp;

  XmFileSelectionBoxCallbackStruct* cbs =
    (XmFileSelectionBoxCallbackStruct*)call_data;

  if (cbs) {

    if (!XmStringGetLtoR(cbs->value, XmSTRING_DEFAULT_CHARSET, &file)) {
      printf("WriteEPS: error\n");
      return;
    }
    
    
    const SbViewportRegion &vp = myViewer->getViewportRegion();
    const SbVec2s &imagePixSize = vp.getViewportSizePixels();
    SbVec2f imageInches;
    float pixPerInch;
    
    pixPerInch = SoOffscreenRenderer::getScreenPixelsPerInch();

    imageInches.setValue( (float)imagePixSize[0] / pixPerInch,
			  (float)imagePixSize[1] / pixPerInch );
    
    SbVec2s postScriptRes;
    postScriptRes.setValue( (short)(imageInches[0]) * dpi,
			    (short)(imageInches[1]) * dpi );

    SbViewportRegion myViewport;
    myViewport.setWindowSize( postScriptRes );
    myViewport.setPixelsPerInch( (float) dpi );
    SoOffscreenRenderer *myRenderer = 
      new SoOffscreenRenderer( myViewport );
    myRenderer->setComponents( SoOffscreenRenderer::RGB );

myRenderer->setBackgroundColor(*((BGMaterial->diffuseColor).getValues(0)));
//myRenderer->setAntialiasing (TRUE, 20);

    SoDirectionalLight *light = myViewer->getHeadlight();
    SoCamera *camera = myViewer->getCamera();

    root->insertChild( camera , 0 );
    root->insertChild( light , 0);

    if( !myRenderer->render( root  ) ) {
      delete myRenderer;
      return;
    }

    root->removeChild( 0 );
    root->removeChild( 0 );

    if( ( fp = fopen( file , "w" ) ) == NULL ) {
      printf("WriteEPS: can't open file %s\n",file );
      Cancel_CB( menu_item , NULL , NULL );
      return;
    }
	printf("Writing to file %s.  Please wait.\n",file );
//    myRenderer->writeToRGB( fp );
    myRenderer->writeToPostScript( fp );
    delete myRenderer;

    XtFree( file );
    fclose( fp );
    Cancel_CB( menu_item , NULL , NULL );
  }

}