/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License, Version 1.0 only * (the "License"). You may not use this file except in compliance * with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2005 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ /* All Rights Reserved */ /* * University Copyright- Copyright (c) 1982, 1986, 1988 * The Regents of the University of California * All Rights Reserved * * University Acknowledgment- Portions of this document are derived from * software developed by the University of California, Berkeley, and its * contributors. */ /* * * Drawing routines used by dpost. Almost no real work is done here. Instead * the required calculations are done in special Postscript procedures that * include: * * * Dl * * x1 y1 x y Dl - * * Starts a new path and then draws a line from the current point * (x, y) to (x1, y1). * * De * * x y a b De - * * Starts a new path and then draws an ellipse that has its left side * at the current point (x, y) and horizontal and vertical axes lengths * given by a and b respectively. * * Da * * x y dx1 dy1 dx2 dy2 Da - * * Starts a new segment and then draws a circular arc from the current * point (x, y) to (x + dx1 + dx2, y + dy1 + dy2). The center of the * circle is at (x + dx1, y + dy1). Arcs always go counter-clockwise * from the starting point to the end point. * * DA * * x y dx1 dy1 dx2 dy2 DA - * * Draws a clockwise arc from (x, y) to (x + dx1 + dx2, y + dy1 + dy2) * with center at (x + dx1, y + dy1). Only needed when we're building * large paths that use arcs and want to control the current point. The * arguments passed to drawarc() will be whatever they would have been * for a counter-clockwise arc, so we need to map them into appropriate * arguments for PostScript's arcn operator. The mapping is, * * x = hpos + dx1' + dx2' * y = vpos + dy1' + dy2' * dx1 = -dx2' * dy1 = -dy2' * dx2 = -dx1' * dy2 = -dy1' * * where primed values represent the drawarc() arguments and (hpos, vpos) * is our current position. * * Ds * * x0 y0 x1 y1 x2 y2 Ds - * * Starts a new segment and then draws a quadratic spline connecting * point ((x0 + x1)/2, (y0 + y1)/2) to ((x1 + x2)/2, (y1 + y2)/2). * The points used in Postscript's curveto procedure are given by, * * x0' = (x0 + 5 * x1) / 6 * x1' = (x2 + 5 * x1) / 6 * x2' = (x1 + x2) / 2 * * with similar equations for the y coordinates. * * By default all the PostScript drawing procedures begin with a newpath (just to * be safe) and end with a stroke, which essentially isolates the path elements * built by the drawing procedures. In order to accommodate big paths built from * smaller pieces each of the PostScript drawing procedures can forced to retain * the path that's being built. That's what happens in beginpath() when an "x X * BeginPath" command is read. beginpath() sets the PostScript variable inpath to * true, and that essentially eliminates the newpath/stroke pair that bracket the * individual pieces. In that case the path is terminated and drawn when dpost * reads an "x X DrawPath" command. * * Early versions of dpost included the PostScript drawing procedures as part of * the prologue, and as a result they were included with every job, even if they * were never used. This version has separated the drawing procedures from the * default prologue (they're now in *drawfile) and only includes them if they're * really needed, which is yet another convenient violation of page independence. * Routine getdraw() is responsible for adding *drawfile to the output file, and * if it can't read *drawfile it continues on as if nothing happened. That means * everything should still work if you append *drawfile to *prologue and then * delete *drawfile. * */ #include <stdio.h> #include <math.h> #include "gen.h" /* general purpose definitions */ #include "ext.h" /* external variable definitions */ int gotdraw = FALSE; /* TRUE when *drawfile has been added */ int gotbaseline = FALSE; /* TRUE after *baselinefile is added */ int inpath = FALSE; /* TRUE if we're putting pieces together */ /* * * All these should be defined in file dpost.c. * */ extern int hpos; extern int vpos; extern int encoding; extern int maxencoding; extern int realencoding; extern char *drawfile; extern char *baselinefile; extern FILE *tf; void drawcirc(int); void drawellip(int, int); static void parsebuf(char *); /*****************************************************************************/ void getdraw(void) { /* * * Responsible for making sure the PostScript drawing procedures are downloaded * from *drawfile. Stuff is done at most once per job, and only if the job needs * them. For now I've decided not to quit if we can't read the drawing file. That * pretty much assumes an old version of prologue is being used that includes all * the drawing procedures. * */ if ( gotdraw == FALSE && access(drawfile, 04) == 0 ) doglobal(drawfile); if ( tf == stdout ) gotdraw = TRUE; } /* End of getdraw */ /*****************************************************************************/ void drawline(int dx, int dy) /* endpoint is (hpos+dx, vpos+dy) */ { /* * * Draws a line from (hpos, vpos) to (hpos+dx, vpos+dy), and leaves the current * position at the endpoint. * */ if ( dx == 0 && dy == 0 ) drawcirc(1); else fprintf(tf, "%d %d %d %d Dl\n", hpos + dx, vpos + dy, hpos, vpos); hgoto(hpos+dx); /* where troff expects to be */ vgoto(vpos+dy); resetpos(); /* not sure where the printer is */ } /* End of drawline */ /*****************************************************************************/ void drawcirc(int d) /* diameter of the circle */ { /* * * Draws a circle of diameter d with the left 'side' of the circle at the * current point. After we're finished drawing we move the current position * to the right side. * */ drawellip(d, d); } /* End of drawcirc */ /*****************************************************************************/ void drawellip(int a, int b) /* axes lengths for the ellipse */ { /* * * Draws an ellipse having axes lengths horizontally and vertically of a and * b. The left side of the ellipse is at the current point. After we're done * drawing the path we move the current position to the right side. * */ if ( a == 0 && b == 0 ) return; fprintf(tf, "%d %d %d %d De\n", hpos, vpos, a, b); hgoto(hpos + a); /* where troff expects to be */ vgoto(vpos); resetpos(); /* not sure where the printer is */ } /* End of drawellip */ /*****************************************************************************/ void drawarc(int dx1, int dy1, int dx2, int dy2, int c) /* dx1, dy1 - vector from current pos to center */ /* dx2, dy2 - from center to end of the arc */ /* c - clockwise if c is A */ { /* * * If c isn't set to 'A' a counter-clockwise arc is drawn from the current point * (hpos, vpos) to (hpos+dx1+dx2, vpos+dy1+dy2). The center of the circle is the * point (hpos+dx1, vpos+dy1). If c is 'A' the arc goes clockwise from the point * (hpos+dx1+dx2, vpos+dy1+dy2) to (hpos, vpos). Clockwise arcs are only needed * if we're building a larger path out of pieces that include arcs, and want to * have PostScript manage the path for us. Arguments (for a clockwise arc) are * what would have been supplied if the arc was drawn in a counter-clockwise * direction, and are converted to values suitable for use with PostScript's arcn * operator. * */ if ( (dx1 != 0 || dy1 != 0) && (dx2 != 0 || dy2 != 0) ) if ( c != 'A' ) fprintf(tf, "%d %d %d %d %d %d Da\n", hpos, vpos, dx1, dy1, dx2, dy2); else fprintf(tf, "%d %d %d %d %d %d DA\n", hpos+dx1+dx2, vpos+dy1+dy2, -dx2, -dy2, -dx1, -dy1); hgoto(hpos + dx1 + dx2); /* where troff expects to be */ vgoto(vpos + dy1 + dy2); resetpos(); /* not sure where the printer is */ } /* End of drawarc */ /*****************************************************************************/ void drawspline(FILE *fp, int flag) /* fp - input for point list */ /* flag - flag!=1 connect end points */ { int x[100], y[100]; int i, N; /* * * Spline drawing routine for Postscript printers. The complicated stuff is * handled by procedure Ds, which should be defined in the library file. I've * seen wrong implementations of troff's spline drawing, so fo the record I'll * write down the parametric equations and the necessary conversions to Bezier * cubic splines (as used in Postscript). * * * Parametric equation (x coordinate only): * * * (x2 - 2 * x1 + x0) 2 (x0 + x1) * x = ------------------ * t + (x1 - x0) * t + --------- * 2 2 * * * The coefficients in the Bezier cubic are, * * * A = 0 * B = (x2 - 2 * x1 + x0) / 2 * C = x1 - x0 * * * while the current point is, * * current-point = (x0 + x1) / 2 * * Using the relationships given in the Postscript manual (page 121) it's easy to * see that the control points are given by, * * * x0' = (x0 + 5 * x1) / 6 * x1' = (x2 + 5 * x1) / 6 * x2' = (x1 + x2) / 2 * * * where the primed variables are the ones used by curveto. The calculations * shown above are done in procedure Ds using the coordinates set up in both * the x[] and y[] arrays. * * A simple test of whether your spline drawing is correct would be to use cip * to draw a spline and some tangent lines at appropriate points and then print * the file. * */ for ( N = 2; N < sizeof(x)/sizeof(x[0]); N++ ) if (fscanf(fp, "%d %d", &x[N], &y[N]) != 2) break; x[0] = x[1] = hpos; y[0] = y[1] = vpos; for (i = 1; i < N; i++) { x[i+1] += x[i]; y[i+1] += y[i]; } /* End for */ x[N] = x[N-1]; y[N] = y[N-1]; for (i = ((flag!=1)?0:1); i < ((flag!=1)?N-1:N-2); i++) fprintf(tf, "%d %d %d %d %d %d Ds\n", x[i], y[i], x[i+1], y[i+1], x[i+2], y[i+2]); hgoto(x[N]); /* where troff expects to be */ vgoto(y[N]); resetpos(); /* not sure where the printer is */ } /* End of drawspline */ /*****************************************************************************/ void beginpath(char *buf, int copy) /* buf - whatever followed "x X BeginPath" */ /* copy - ignore *buf if FALSE */ { /* * * Called from devcntrl() whenever an "x X BeginPath" command is read. It's used * to mark the start of a sequence of drawing commands that should be grouped * together and treated as a single path. By default the drawing procedures in * *drawfile treat each drawing command as a separate object, and usually start * with a newpath (just as a precaution) and end with a stroke. The newpath and * stroke isolate individual drawing commands and make it impossible to deal with * composite objects. "x X BeginPath" can be used to mark the start of drawing * commands that should be grouped together and treated as a single object, and * part of what's done here ensures that the PostScript drawing commands defined * in *drawfile skip the newpath and stroke, until after the next "x X DrawPath" * command. At that point the path that's been built up can be manipulated in * various ways (eg. filled and/or stroked with a different line width). * * String *buf is unnecessary and is only included for compatibility with an early * verion of that's still in use. In that version "x X BeginObject" marked the * start of a graphical object, and whatever followed it was passed along in *buf * and copied to the output file. Color selection is one of the options that's * available in parsebuf(), so if we get here we add *colorfile to the output * file before doing anything important. * */ if ( inpath == FALSE ) { endtext(); getdraw(); getcolor(); fprintf(tf, "gsave\n"); fprintf(tf, "newpath\n"); fprintf(tf, "%d %d m\n", hpos, vpos); fprintf(tf, "/inpath true def\n"); if ( copy == TRUE ) fprintf(tf, "%s", buf); inpath = TRUE; } /* End if */ } /* End of beginpath */ /*****************************************************************************/ void drawpath(char *buf, int copy) { /* * * Called from devcntrl() whenever an "x X DrawPath" command is read. It marks the * end of the path started by the last "x X BeginPath" command and uses whatever * has been passed along in *buf to manipulate the path (eg. fill and/or stroke * the path). Once that's been done the drawing procedures are restored to their * default behavior in which each drawing command is treated as an isolated path. * The new version (called after "x X DrawPath") has copy set to FALSE, and calls * parsebuf() to figure out what goes in the output file. It's a feeble attempt * to free users and preprocessors (like pic) from having to know PostScript. The * comments in parsebuf() describe what's handled. * * In the early version a path was started with "x X BeginObject" and ended with * "x X EndObject". In both cases *buf was just copied to the output file, and * was expected to be legitimate PostScript that manipulated the current path. * The old escape sequence will be supported for a while (for Ravi), and always * call this routine with copy set to TRUE. * * */ if ( inpath == TRUE ) { if ( copy == TRUE ) fprintf(tf, "%s", buf); else parsebuf(buf); fprintf(tf, "grestore\n"); fprintf(tf, "/inpath false def\n"); reset(); inpath = FALSE; } /* End if */ } /* End of drawpath */ /*****************************************************************************/ static void parsebuf(char *buf) /* whatever followed "x X DrawPath" */ { char *p; /* usually the next token */ char *p1; /* for grabbing arguments */ char *pend; /* end of the original string (ie. *buf) */ int gsavelevel = 0; /* non-zero if we've done a gsave */ /* * * Simple minded attempt at parsing the string that followed an "x X DrawPath" * command. Everything not recognized here is simply ignored - there's absolutely * no error checking and what was originally in buf is clobbered by strtok(). * A typical *buf might look like, * * gray .9 fill stroke * * to fill the current path with a gray level of .9 and follow that by stroking the * outline of the path. Since unrecognized tokens are ignored the last example * could also be written as, * * with gray .9 fill then stroke * * The "with" and "then" strings aren't recognized tokens and are simply discarded. * The "stroke", "fill", and "wfill" force out appropriate PostScript code and are * followed by a grestore. In otherwords changes to the grahics state (eg. a gray * level or color) are reset to default values immediately after the stroke, fill, * or wfill tokens. For now "fill" gets invokes PostScript's eofill operator and * "wfill" calls fill (ie. the operator that uses the non-zero winding rule). * * The tokens that cause temporary changes to the graphics state are "gray" (for * setting the gray level), "color" (for selecting a known color from the colordict * dictionary defined in *colorfile), and "line" (for setting the line width). All * three tokens can be extended since strncmp() makes the comparison. For example * the strings "line" and "linewidth" accomplish the same thing. Colors are named * (eg. "red"), but must be appropriately defined in *colorfile. For now all three * tokens must be followed immediately by their single argument. The gray level * (ie. the argument that follows "gray") should be a number between 0 and 1, with * 0 for black and 1 for white. * * To pass straight PostScript through enclose the appropriate commands in double * quotes. Straight PostScript is only bracketed by the outermost gsave/grestore * pair (ie. the one from the initial "x X BeginPath") although that's probably * a mistake. Suspect I may have to change the double quote delimiters. * */ pend = buf + strlen(buf); p = strtok(buf, " \n"); while ( p != NULL ) { if ( gsavelevel == 0 ) { fprintf(tf, "gsave\n"); gsavelevel++; } /* End if */ if ( strcmp(p, "stroke") == 0 ) { fprintf(tf, "closepath stroke\ngrestore\n"); gsavelevel--; } else if ( strcmp(p, "openstroke") == 0 ) { fprintf(tf, "stroke\ngrestore\n"); gsavelevel--; } else if ( strcmp(p, "fill") == 0 ) { fprintf(tf, "eofill\ngrestore\n"); gsavelevel--; } else if ( strcmp(p, "wfill") == 0 ) { fprintf(tf, "fill\ngrestore\n"); gsavelevel--; } else if ( strcmp(p, "sfill") == 0 ) { fprintf(tf, "eofill\ngrestore\ngsave\nstroke\ngrestore\n"); gsavelevel--; } else if ( strncmp(p, "gray", strlen("gray")) == 0 ) { p1 = strtok(NULL, " \n"); fprintf(tf, "%s setgray\n", p1); } else if ( strncmp(p, "color", strlen("color")) == 0 ) { p1 = strtok(NULL, " \n"); fprintf(tf, "/%s setcolor\n", p1); } else if ( strncmp(p, "line", strlen("line")) == 0 ) { p1 = strtok(NULL, " \n"); fprintf(tf, "%s resolution mul 2 div setlinewidth\n", p1); } else if ( strncmp(p, "reverse", strlen("reverse")) == 0 ) fprintf(tf, "reversepath\n"); else if ( *p == '"' ) { for ( ; gsavelevel > 0; gsavelevel-- ) fprintf(tf, "grestore\n"); if ( (p1 = p + strlen(p)) < pend ) *p1 = ' '; p = strtok(p, "\"\n"); fprintf(tf, "%s\n", p); } /* End else */ p = strtok(NULL, " \n"); } /* End while */ for ( ; gsavelevel > 0; gsavelevel-- ) fprintf(tf, "grestore\n"); } /* End of parsebuf */ /*****************************************************************************/ static void getbaseline(void) { /* * * Responsible for making sure the PostScript procedures needed for printing text * along an arbitrary baseline are downloaded from *baselinefile. Done at most * once per job, and only if the the stuff is really used. * */ if ( gotbaseline == FALSE && access(baselinefile, 04) == 0 ) doglobal(baselinefile); if ( tf == stdout ) gotbaseline = TRUE; } /* End of getbaseline */ /*****************************************************************************/ void newbaseline(char *buf) /* whatever followed "x X NewBaseline" */ { char *p; /* for eliminating white space etc. */ /* * * Called from devcntrl() whenever an "x X NewBaseline" command is recognized. We * assume whatever is in *buf is a set of parametric equations that describe the * new baseline. Equations for x(t), y(t), dx/dt, and dy/dt must be written in * PostScript, bracketed by { and } characters, and supplied in exactly that order. * In particular the equation for x must come first in *buf and it ends up as the * last one on the stack, while the equation for dy/dt comes last (in *buf) and * ends up on the top of the PostScript stack. For example if *buf is given by, * * {} {180 mul 3.1416 div cos} {pop 1} {180 mul 3.1416 div sin neg} * * text will be printed along the curve y = cos(x). * * Angles given in radians must be converted to degrees for the PostScript trig * functions, and things are scaled so that 1 unit maps into 1 inch. In the last * example the cosine curve that describes the baseline has an amplitude of 1 inch. * As another example of this rather confusing syntax if *buf is, * * {} {} {pop 1} {pop 1} * * the baseline will be the 45 degree line y = x. * * When any of the four functions is used they're called with a single number on * the stack that's equal to the current value of the parameter t. The coordinate * system axes run parallel to the PostScript coordinate system that's currently * being used. * */ for ( p = buf; *p; p++ ) /* eliminate trailing '\n' */ if ( *p == '\n' ) { *p = '\0'; break; } /* End if */ for ( p = buf; *p && (*p == ' ' || *p == ':'); p++ ) ; if ( *p != '\0' ) { /* something's there */ endtext(); getbaseline(); fprintf(tf, "mark resolution %s newbaseline\n", p); t_sf(); resetpos(); } /* End if */ } /* End of newbaseline */ /*****************************************************************************/ void drawtext(char *buf) /* whatever followed "x X DrawText */ { char *p; /* for eliminating white space etc. */ /* * * Called from devcntrl() whenever an "x X DrawText command is recognized. *buf * should contain three arguments in the following order. First comes the text we * want to print along the current baseline. Right now the string should be given * as a PostScript string using characters '(' and ')' as the delimiters. Next in * *buf comes a justification mode that can be the words left, right, or center. * Last comes a number that represents the starting value of the parameter t that's * given as the argument to the parametric equations that describe the current * baseline. For example if *buf is given by, * * (hello world) left .5 * * hello world will be printed along the path described by the current baseline * and left justified at whatever (x(.5), y(.5)) happens to be. Usually will be * preceeded by an "x X NewBaseline" call that defines the current baseline. The * origin of the coordinate system used by the parametric equations will be the * current point. * */ for ( p = buf; *p; p++ ) /* eliminate trailing '\n' */ if ( *p == '\n' ) { *p = '\0'; break; } /* End if */ for ( p = buf; *p && (*p == ' ' || *p == ':'); p++ ) ; if ( *p != '\0' ) { /* something's there */ endtext(); getbaseline(); xymove(hpos, vpos); fprintf(tf, "mark %s drawfunnytext\n", p); resetpos(); } /* End if */ } /* End of drawtext */ /*****************************************************************************/ void settext(char *buf) { char *p; /* * * Does whatever is needed to ensure any text that follows will be set along the * curve described by the PostScript procedures listed in *buf. If *buf doesn't * contain anything useful (eg. just a newline) things are restored to whatever * they originally were. Doesn't work well if we try to start in the middle of a * line of text. * * The parametric equations needed are, * * x = f(t) * y = g(t) * dx/dt = f'(t) * dy/dt = g'(t) * * and must be given as proper PostScript procedures. The equation for x must come * first (ie. it ends up on the bottom of the stack) and the equation for dy/dt * must be given last (ie. it ends up on top of the stack). For example if *buf * is given by, * * {} {180 mul 3.1416 div cos} {pop 1} {180 mul 3.1416 div sin neg} * * text will be set along the curve y=cos(x). * */ endtext(); getbaseline(); for ( p = buf; *p && *p == ' '; p++ ) ; if ( *p && *p != '\n' ) { encoding = maxencoding + 2; fprintf(tf, "mark resolution %s newbaseline\n", buf); } else encoding = realencoding; fprintf(tf, "%d setdecoding\n", encoding); resetpos(); } /* End of settext */
