clip.c

Intro/: Directory containing introductory examples. HelloWorld.c A simple program that draws a bo

#include <phigs.h>			/* get HP-PHIGS definitions for C */
#include <stdio.h>			/* get standard I/O definitions */
#define  FALSE			0	/* boolean false is integer 0 */
#define	 TRUE			1	/* boolean true is integer 1 */
#define	 SimplexSansSerif	-2	/* sent to "pset_text_font" */
#define	 BoldSansSerif		-4	/* sent to "pset_text_font" */

main()					/* file "Clip.c" */
{
    Pint	WorkstnID = 1;		/* workstation identifier */
    Pint	ConnID;			/* connection identifier */
    Pint	WorkstnType = POIDDX;	/* out/in, direct, dbl bfr, Xwindow */
    Pint	TheCurve = 1;		/* structure ID (chosen by user) */
    Ppoint	LinePts[100];		/* points for the polyline */
    Ppoint_list	LineData;		/* data for the polyline */
    static Ptext_align	CenterTop =	/* alignment for the main title */
		{PHOR_CTR, PVERT_TOP};
    static Ptext_align	CenterBottom =	/* alignment for the x-axis title */
		{PHOR_CTR, PVERT_BOTTOM};
    static Pvec	ToTheLeft = {-1.0, 0.0};/* sent to "pset_char_up_vec" */
    Ppoint	Point;			/* one point (for various purposes) */
    FILE	*datafile;		/* file pointer */
    int		I = 0;			/* loop control variable */

    /*=== read data file into the structure array ==========================*/
    datafile = fopen("data", "r");	/* open data file (2 numbers/line) */
    while (fscanf(datafile, "%f%f", &LinePts[I].x, &LinePts[I].y) != EOF)
	I++;
    fclose(datafile);
    LineData.num_points = I;
    LineData.points = LinePts;
    /*=== set up HP-PHIGS to plot data =====================================*/
    popen_phigs((char *) stderr, 0);	/* errors go to "stderr" */
    pescape_u4("/dev/screen/phigs_window", &ConnID);
    popen_ws(WorkstnID, (void *) ConnID, WorkstnType);
    DefineView(WorkstnID, 1,		/* mapping for view index 1: */
      0.0,  1.0,  0.0,  1.0,		/*   window: 0-1, 0-1 */
      0.12, 0.98, 0.10, 0.88,		/*   viewport: in a subset */
      FALSE);				/*   don't clip at view window */
    DefineView(WorkstnID, 2,		/* mapping for view index 2: */
      0.0,  1.0,  0.0,  1.0,		/*   window: 0-1, 0-1 */
      0.0,  1.0,  0.0,  1.0,		/*   viewport: 0-1, 0-1 */
      TRUE);				/*   clip at view window */
    DefineView(WorkstnID, 3,		/* mapping for view index 3: */
      0.0,  1.0,  0.0,  1.0,		/*   window: 0-1, 0-1 */
      0.12, 0.98, 0.10, 0.88,		/*   viewport: in a subset */
      TRUE);				/*   clip at view window */
    popen_struct(TheCurve);
    /*=== create the labels ================================================*/
    pset_view_ind(2);
    /*--- do main title ----------------------------------------------------*/
    pset_text_font(BoldSansSerif);
    pset_text_align(&CenterTop);
    pset_char_ht(0.05);
    Point.x = 0.5, Point.y = 1.0;
    ptext(&Point, "VOLTAGE VARIANCE");
    /*--- do the x-axis title ----------------------------------------------*/
    pset_text_font(SimplexSansSerif);
    pset_text_align(&CenterBottom);
    pset_char_ht(0.03);
    Point.x = 0.5, Point.y = 0.0;
    ptext(&Point, "Time (seconds)");
    /*--- do the y-axis title ----------------------------------------------*/
    pset_char_up_vec(&ToTheLeft);
    pset_text_align(&CenterTop);
    Point.x = 0.0, Point.y = 0.5;
    ptext(&Point, "Voltage");
    /*=== graph the data ===================================================*/
    pset_view_ind(1);
    DefineRectangle(0.0, 1.0, 0.0, 1.0);
    ppolyline(&LineData);
    /*--- define the tic marks ---------------------------------------------*/
    pset_view_ind(3);
    DefineTics('X', 0.0, 0.0, 1.0, 0.01, 0.01, 5);
    DefineTics('X', 1.0, 0.0, 1.0, 0.01, 0.01, 5);
    DefineTics('Y', 0.0, 0.0, 1.0, 0.01, 0.01, 5);
    DefineTics('Y', 1.0, 0.0, 1.0, 0.01, 0.01, 5);
    pclose_struct();
    /*=== post the image and close up shop =================================*/
    ppost_struct(WorkstnID, TheCurve, 1.0);
    pupd_ws(WorkstnID, PFLAG_PERFORM);	/* (regeneration flag) */
    pclose_ws(WorkstnID);
    pclose_phigs();
}
/****************************************************************************/
DefineView(WorkstnID, ViewIndex, Wxmin, Wxmax, Wymin, Wymax,
  Vxmin, Vxmax, Vymin, Vymax, ClipAtWindow)
int	WorkstnID;			/* workstation identifier */
int	ViewIndex;			/* the view being defined */
float	Wxmin, Wxmax, Wymin, Wymax;	/* view window limits */
float	Vxmin, Vxmax, Vymin, Vymax;	/* projection viewport limits */
int	ClipAtWindow;			/* window (or display surface?) */
{
    Pview_map	Mapping;		/* window-onto-viewport mapping */
    Pint	ErrorReturn;		/* error return variable */
    Pview_rep	ViewRep;		/* complete description of view */
    int		I, J;			/* loop control variables */

    /*--- define the view orientation matrix as identity -------------------*/
    for (I = 0; I < 3; I++)
	for (J = 0; J < 3; J++)
	    ViewRep.ori_matrix[I][J] = (I == J);
    /*--- define view mapping matrix ---------------------------------------*/
    Mapping.win.x_min = Wxmin;			/* \			    */
    Mapping.win.x_max = Wxmax;			/*  \ put individual values */
    Mapping.win.y_min = Wymin;			/*  / into the structure    */
    Mapping.win.y_max = Wymax;			/* /			    */
    Mapping.proj_vp.x_min = Vxmin;		/* \			    */
    Mapping.proj_vp.x_max = Vxmax;		/*  \ put individual values */
    Mapping.proj_vp.y_min = Vymin;		/*  / into the structure    */
    Mapping.proj_vp.y_max = Vymax;		/* /			    */
    peval_view_map_matrix(&Mapping, &ErrorReturn, ViewRep.map_matrix);
    if (ErrorReturn != 0) {			/* did we get an error? */
        printf("%s %d %s %s\n", "Error", ErrorReturn, "occurred during",
          "call to Evaluate View Mapping Matrix.");
        exit(1);
    }
    /*--- define the clip limits -------------------------------------------*/
    if (ClipAtWindow)
	ViewRep.clip_limit = Mapping.proj_vp;	/* clip at viewport */
    else {
	ViewRep.clip_limit.x_min = 0.0;		/* \		       */
	ViewRep.clip_limit.x_max = 1.0;		/*  \ clip at edges of */
	ViewRep.clip_limit.y_min = 0.0;		/*  / display surface  */
	ViewRep.clip_limit.y_max = 1.0;		/* /		       */
    }
    /*--- define clip indicator --------------------------------------------*/
    ViewRep.xy_clip = PIND_CLIP;
    /*--- set the view representation --------------------------------------*/
    pset_view_rep(WorkstnID, ViewIndex, &ViewRep);
}
/****************************************************************************/
DefineRectangle(Xmin, Xmax, Ymin, Ymax)
float	Xmin, Xmax, Ymin, Ymax;			/* rectangle's limits */
{
    Ppoint_list	Rectangle;
    Ppoint	Corners[5];
      
    Rectangle.num_points = 5;
    Corners[0].x = Xmin, Corners[0].y = Ymin;	/* lower left corner */
    Corners[1].x = Xmax, Corners[1].y = Ymin;	/* lower right corner */
    Corners[2].x = Xmax, Corners[2].y = Ymax;	/* upper right corner */
    Corners[3].x = Xmin, Corners[3].y = Ymax;	/* upper left corner */
    Corners[4].x = Xmin, Corners[4].y = Ymin;	/* lower left corner */
    Rectangle.points = Corners;
    ppolyline(&Rectangle);
}
/****************************************************************************/
DefineTics(Axis, Location, Start, End, Delta, Size, Major)
char	Axis;				/* which axis are the tics for? */
float	Location;			/* where is this line of tics? */
float	Start;				/* where do the tics start? */
float	End;				/* where do they end? */
float	Delta;				/* draw a tic every how often? */
float	Size;				/* how big should the tics be? */
int	Major;				/* how often does major tic occur? */
{
    int		TicNumber = 0;		/* which tic are we on? */
    Ppoint_list	Tic;			/* polyline data */
    Ppoint	TicPoints[2];		/* both ends of a tic mark */
    float	CurrentX, CurrentY;	/* loop control variables */
    float	Length;			/* length of current tic mark */

    if ((Axis == 'x') || (Axis == 'X')) {
	for (CurrentX = Start; CurrentX <= End; CurrentX+=Delta,TicNumber++) {
	    Length = Size * (1 + (TicNumber % Major == 0));
	    Tic.num_points = 2;
	    TicPoints[0].x = CurrentX;		/* x: bottom of tic mark */
	    TicPoints[0].y = Location - Length;	/* y: bottom of tic mark */
	    TicPoints[1].x = CurrentX;		/* x: top of tic mark */
	    TicPoints[1].y = Location + Length;	/* y: top of tic mark */
	    Tic.points = TicPoints;
	    ppolyline(&Tic);
	}
    }
    else if ((Axis == 'y') || (Axis == 'Y')) {
	for (CurrentY = Start; CurrentY <= End; CurrentY+=Delta,TicNumber++) {
	    Length = Size * (1 + (TicNumber % Major == 0));
	    Tic.num_points = 2;
	    TicPoints[0].x = Location - Length;	/* x: bottom of tic mark */
	    TicPoints[0].y = CurrentY;		/* y: bottom of tic mark */
	    TicPoints[1].x = Location + Length;	/* x: top of tic mark */
	    TicPoints[1].y = CurrentY;		/* y: top of tic mark */
	    Tic.points = TicPoints;
	    ppolyline(&Tic);
	}
    }
}