# vector-clip
--- graphics.c.ORIG	Wed Sep 15 16:30:29 1999
+++ graphics.c	Thu Dec  2 13:16:57 1999
@@ -1369,7 +1369,6 @@
 
     /* label first y axis tics */
     if (ytics) {
-	int axis = map_x(ZERO);
 	/* set the globals ytick2d_callback() needs */
 
 	if (rotate_ytics && (*t->text_angle) (1)) {
@@ -1388,8 +1387,8 @@
 	else
 	    tic_mirror = -1;	/* no thank you */
 
-	if ((ytics & TICS_ON_AXIS) && !log_array[FIRST_X_AXIS] && inrange(axis, xleft, xright)) {
-	    tic_start = axis;
+	if ((ytics & TICS_ON_AXIS) && !log_array[FIRST_X_AXIS] && inrange(0.0, x_min, x_max)) {
+	    tic_start = map_x(0.0);
 	    tic_direction = -1;
 	    if (ytics & TICS_MIRROR)
 		tic_mirror = tic_start;
@@ -1409,7 +1408,6 @@
     }
     /* label first x axis tics */
     if (xtics) {
-	int axis = map_y(ZERO);
 	/* set the globals xtick2d_callback() needs */
 
 	if (rotate_xtics && (*t->text_angle) (1)) {
@@ -1426,8 +1424,8 @@
 	    tic_mirror = ytop;
 	else
 	    tic_mirror = -1;	/* no thank you */
-	if ((xtics & TICS_ON_AXIS) && !log_array[FIRST_Y_AXIS] && inrange(axis, ybot, ytop)) {
-	    tic_start = axis;
+	if ((xtics & TICS_ON_AXIS) && !log_array[FIRST_Y_AXIS] && inrange(0.0, y_min, y_max)) {
+	    tic_start = map_y(0.0);
 	    tic_direction = -1;
 	    if (xtics & TICS_MIRROR)
 		tic_mirror = tic_start;
@@ -1454,7 +1452,6 @@
     /* label second y axis tics */
     if (y2tics) {
 	/* set the globalss ytick2d_callback() needs */
-	int axis = map_x(ZERO);
 
 	if (rotate_y2tics && (*t->text_angle) (1)) {
 	    tic_hjust = CENTRE;
@@ -1470,8 +1467,8 @@
 	    tic_mirror = xleft;
 	else
 	    tic_mirror = -1;	/* no thank you */
-	if ((y2tics & TICS_ON_AXIS) && !log_array[FIRST_X_AXIS] && inrange(axis, xleft, xright)) {
-	    tic_start = axis;
+	if ((y2tics & TICS_ON_AXIS) && !log_array[FIRST_X_AXIS] && inrange(0.0, x_min, x_max)) {
+	    tic_start = map_x(0.0);
 	    tic_direction = 1;
 	    if (y2tics & TICS_MIRROR)
 		tic_mirror = tic_start;
@@ -1490,7 +1487,6 @@
     }
     /* label second x axis tics */
     if (x2tics) {
-	int axis = map_y(ZERO);
 	/* set the globals xtick2d_callback() needs */
 
 	if (rotate_x2tics && (*t->text_angle) (1)) {
@@ -1507,8 +1503,8 @@
 	    tic_mirror = ybot;
 	else
 	    tic_mirror = -1;	/* no thank you */
-	if ((x2tics & TICS_ON_AXIS) && !log_array[SECOND_Y_AXIS] && inrange(axis, ybot, ytop)) {
-	    tic_start = axis;
+	if ((x2tics & TICS_ON_AXIS) && !log_array[SECOND_Y_AXIS] && inrange(0.0, y_min, y_max)) {
+	    tic_start = map_y(0.0);
 	    tic_direction = 1;
 	    if (x2tics & TICS_MIRROR)
 		tic_mirror = tic_start;
@@ -1560,45 +1556,58 @@
 
     x_axis = FIRST_X_AXIS;
     y_axis = FIRST_Y_AXIS;	/* chose scaling */
-    axis_zero[FIRST_Y_AXIS] = map_y(0.0);
-    axis_zero[FIRST_X_AXIS] = map_x(0.0);
 
-    if (axis_zero[FIRST_Y_AXIS] < ybot || is_log_y)
+    if (y_min >= 0.0 && y_max >= 0.0 || is_log_y)
 	axis_zero[FIRST_Y_AXIS] = ybot;		/* save for impulse plotting */
-    else if (axis_zero[FIRST_Y_AXIS] >= ytop)
+    else if (y_min <= 0.0 && y_max <= 0.0)
 	axis_zero[FIRST_Y_AXIS] = ytop;
-    else if (xzeroaxis.l_type > -3) {
-	term_apply_lp_properties(&xzeroaxis);
-	(*t->move) (xleft, axis_zero[FIRST_Y_AXIS]);
-	(*t->vector) (xright, axis_zero[FIRST_Y_AXIS]);
-    }
-    if ((yzeroaxis.l_type > -3) && !is_log_x
-	&& axis_zero[FIRST_X_AXIS] >= xleft
-	&& axis_zero[FIRST_X_AXIS] < xright) {
-	term_apply_lp_properties(&yzeroaxis);
-	(*t->move) (axis_zero[FIRST_X_AXIS], ybot);
-	(*t->vector) (axis_zero[FIRST_X_AXIS], ytop);
+    else {
+	axis_zero[FIRST_X_AXIS] = map_y(0.0);
+	if (xzeroaxis.l_type > -3) {
+	    term_apply_lp_properties(&xzeroaxis);
+	    (*t->move) (xleft, axis_zero[FIRST_Y_AXIS]);
+	    (*t->vector) (xright, axis_zero[FIRST_Y_AXIS]);
+	}
+    }
+    if (x_min >= 0.0 && x_max >= 0.0)
+	axis_zero[FIRST_Y_AXIS] = xleft;
+    else if (x_min <= 0.0 && x_max <= 0.0)
+	axis_zero[FIRST_Y_AXIS] = xright;
+    else {
+	axis_zero[FIRST_Y_AXIS] = map_x(0.0);
+	if ((yzeroaxis.l_type > -3) && !is_log_x) {
+	    term_apply_lp_properties(&yzeroaxis);
+	    (*t->move) (axis_zero[FIRST_X_AXIS], ybot);
+	    (*t->vector) (axis_zero[FIRST_X_AXIS], ytop);
+	}
     }
+
     x_axis = SECOND_X_AXIS;
     y_axis = SECOND_Y_AXIS;	/* chose scaling */
-    axis_zero[SECOND_Y_AXIS] = map_y(0.0);
-    axis_zero[SECOND_X_AXIS] = map_x(0.0);
 
-    if (axis_zero[SECOND_Y_AXIS] < ybot || is_log_y2)
+    if (is_log_y2 || y_min >= 0.0 && y_max >= 0.0)
 	axis_zero[SECOND_Y_AXIS] = ybot;  /* save for impulse plotting */
-    else if (axis_zero[SECOND_Y_AXIS] >= ytop)
+    else if (y_min <= 0.0 && y_max <= 0.0)
 	axis_zero[SECOND_Y_AXIS] = ytop;
-    else if (x2zeroaxis.l_type > -3) {
-	term_apply_lp_properties(&x2zeroaxis);
-	(*t->move) (xleft, axis_zero[SECOND_Y_AXIS]);
-	(*t->vector) (xright, axis_zero[SECOND_Y_AXIS]);
-    }
-    if ((y2zeroaxis.l_type > -3) && !is_log_x2 &&
-	axis_zero[SECOND_X_AXIS] >= xleft &&
-	axis_zero[SECOND_X_AXIS] < xright) {
-	term_apply_lp_properties(&y2zeroaxis);
-	(*t->move) (axis_zero[SECOND_X_AXIS], ybot);
-	(*t->vector) (axis_zero[SECOND_X_AXIS], ytop);
+    else {
+	axis_zero[SECOND_X_AXIS] = map_y(0.0);
+	if (x2zeroaxis.l_type > -3) {
+	    term_apply_lp_properties(&x2zeroaxis);
+	    (*t->move) (xleft, axis_zero[SECOND_Y_AXIS]);
+	    (*t->vector) (xright, axis_zero[SECOND_Y_AXIS]);
+	}
+    }
+    if (y_min >= 0.0 && y_max >= 0.0)
+	axis_zero[SECOND_Y_AXIS] = xleft;
+    else if (x_min <= 0.0 && x_max <= 0.0)
+	axis_zero[SECOND_Y_AXIS] = xright;
+    else {
+	axis_zero[SECOND_Y_AXIS] = map_x(0.0);
+	if ((y2zeroaxis.l_type > -3) && !is_log_x2) {
+	    term_apply_lp_properties(&y2zeroaxis);
+	    (*t->move) (axis_zero[SECOND_X_AXIS], ybot);
+	    (*t->vector) (axis_zero[SECOND_X_AXIS], ytop);
+	}
     }
     /* DRAW PLOT BORDER */
     if (draw_border) {
@@ -2739,14 +2748,61 @@
     int i;
     int x1, y1, x2, y2;
     struct termentry *t = term;
+    TBOOLEAN head;
+    struct coordinate GPHUGE points[2];
+    double ex, ey;
+    double lx[2], ly[2];
 
     for (i = 0; i < plot->p_count; i++) {
-	if (plot->points[i].type == INRANGE) {
-	    x1 = map_x(plot->points[i].xlow);
-	    y1 = map_y(plot->points[i].ylow);
-	    x2 = map_x(plot->points[i].xhigh);
-	    y2 = map_y(plot->points[i].yhigh);
-	    (*t->arrow) (x1, y1, x2, y2, TRUE);
+	points[0] = plot->points[i];
+	points[1].x = plot->points[i].xhigh;
+	points[1].y = plot->points[i].yhigh;
+	if (inrange(points[1].x, x_min, x_max) &&
+	    inrange(points[1].y, y_min, y_max)) {
+	    /* to inrange */
+	    points[1].type = INRANGE;
+	    x2 = map_x(points[1].x);
+	    y2 = map_y(points[1].y);
+	    head = TRUE;
+	    if (points[0].type == INRANGE) {
+		x1 = map_x(points[0].x);
+		y1 = map_y(points[0].y);
+		(*t->arrow) (x1, y1, x2, y2, head);
+	    } else if (points[0].type == OUTRANGE) {
+		/* from outrange to inrange */
+		if (clip_lines1) {
+		    edge_intersect(points, 1, &ex, &ey);
+		    x1 = map_x(ex);
+		    y1 = map_y(ey);
+		    (*t->arrow) (x1, y1, x2, y2, head);
+		}
+	    }
+	} else {
+	    /* to outrange */
+	    points[1].type = OUTRANGE;
+	    head = FALSE;
+	    if (points[0].type == INRANGE) {
+		/* from inrange to outrange */
+		if (clip_lines1) {
+		    x1 = map_x(points[0].x);
+		    y1 = map_y(points[0].y);
+		    edge_intersect(points, 1, &ex, &ey);
+		    x2 = map_x(ex);
+		    y2 = map_y(ey);
+		    (*t->arrow) (x1, y1, x2, y2, head);
+		}
+	    } else if (points[0].type == OUTRANGE) {
+		/* from outrange to outrange */
+		if (clip_lines2) {
+		    if (two_edge_intersect(points, 1, lx, ly)) {
+			x1 = map_x(lx[0]);
+			y1 = map_y(ly[0]);
+			x2 = map_x(lx[1]);
+			y2 = map_y(ly[1]);
+			(*t->arrow) (x1, y1, x2, y2, head);
+		    }
+		}
+	    }
 	}
     }
 }