Rationalise box handling (needs debugging)

10 files changed, 313 insertions, 290 deletions

diff --git a/src/boxvec.c b/src/boxvec.c
new file mode 100644
index 0000000..06754e6
--- /dev/null
+++ b/src/boxvec.c
@@ -0,0 +1,98 @@
+/*
+ * boxvec.c
+ *
+ * Copyright © 2016 Thomas White <taw@bitwiz.org.uk>
+ *
+ * This file is part of Colloquium.
+ *
+ * Colloquium is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+#include "boxvec.h"
+
+
+int bv_len(struct boxvec *vec)
+{
+	return vec->n_boxes;
+}
+
+
+extern struct boxvec *bv_new()
+{
+	struct boxvec *n = malloc(sizeof(struct boxvec));
+	if ( n == NULL ) return NULL;
+
+	n->n_boxes = 0;
+	n->max_boxes = 0;
+	n->boxes = NULL;
+
+	return NULL;
+}
+
+
+int bv_ensure_space(struct boxvec *vec, int n)
+{
+	struct wrap_box **t;
+	if ( vec == NULL ) return 1;
+	if ( vec->max_boxes > n ) return 0;
+
+	n = (n/32)*32 + 32;
+	t = realloc(vec->boxes, n*sizeof(struct wrap_box *));
+	if ( t == NULL ) return 1;
+
+	vec->boxes = t;
+	return 0;
+}
+
+
+int bv_add(struct boxvec *vec, struct wrap_box *bx)
+{
+	if ( vec == NULL ) return 1;
+	if ( bv_ensure_space(vec, vec->n_boxes+1) ) return 1;
+	vec->boxes[vec->n_boxes++] = bx;
+	return 0;
+}
+
+
+struct wrap_box *bv_box(struct boxvec *vec, int i)
+{
+	assert(vec != NULL);
+	if ( i >= vec->n_boxes ) return NULL;
+	return vec->boxes[i];
+}
+
+
+struct wrap_box *bv_last(struct boxvec *vec)
+{
+	return vec->boxes[vec->n_boxes-1];
+}
+
+
+void bv_free(struct boxvec *vec)
+{
+	if ( vec == NULL ) return;
+	free(vec->boxes);
+	free(vec);
+}
+
diff --git a/src/boxvec.h b/src/boxvec.h
new file mode 100644
index 0000000..e830837
--- /dev/null
+++ b/src/boxvec.h
@@ -0,0 +1,63 @@
+/*
+ * boxvec.h
+ *
+ * Copyright © 2016 Thomas White <taw@bitwiz.org.uk>
+ *
+ * This file is part of Colloquium.
+ *
+ * Colloquium is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifndef BOXVEC_H
+#define BOXVEC_H
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+
+
+/* A vector of boxes */
+struct boxvec
+{
+	int n_boxes;
+	int max_boxes;
+	struct wrap_box **boxes;
+};
+
+
+/* Length of a boxvec */
+extern int bv_len(struct boxvec *vec);
+
+/* Create a bxvec or boxvec */
+extern struct boxvec *bv_new(void);
+
+/* Ensure space in a bxvec or boxvec */
+extern int bv_ensure_space(struct boxvec *vec, int n);
+
+/* Add to a bxvec or boxvec */
+extern int bv_add(struct boxvec *vec, struct wrap_box *bx);
+
+/* Get a box from a boxvec or bxvec */
+extern struct wrap_box *bv_box(struct boxvec *vec, int i);
+extern struct wrap_box *bv_last(struct boxvec *vec);
+
+/* Free a bxvec or boxvec */
+extern void bv_free(struct boxvec *vec);
+
+#endif /* BOXVEC_H */
diff --git a/src/frame.c b/src/frame.c
index 5b16f32..c1dfd39 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -32,6 +32,7 @@
 #include "sc_parse.h"
 #include "frame.h"
 #include "wrap.h"
+#include "boxvec.h"
 
 
 static int alloc_ro(struct frame *fr)
@@ -66,13 +67,7 @@ struct frame *frame_new()
 
 	n->scblocks = NULL;
 
-	n->boxes = malloc(sizeof(struct wrap_line));
-	if ( n->boxes == NULL ) {
-		fprintf(stderr, "Failed to allocate boxes.\n");
-		free(n);
-		return NULL;
-	}
-	initialise_line(n->boxes);
+	n->boxes = bv_new();
 
 	return n;
 }
diff --git a/src/frame.h b/src/frame.h
index f22f5f8..11ad36b 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -55,17 +55,17 @@ struct frame
 	int                       max_children;
 
 	SCBlock                  *scblocks;
-	struct wrap_line         *boxes;  /* The unwrapped boxes */
+	struct boxvec            *boxes;  /* The unwrapped boxes */
 	int                       visited;
 
+	int                       n_paragraphs;
+	struct boxvec           **paragraphs;
+	int                      *paragraph_start_lines;
+
 	int                       n_lines;
 	int                       max_lines;
 	struct wrap_line         *lines;
 
-	int                       n_paragraphs;
-	struct wrap_line        **paragraphs;
-	int                      *paragraph_start_lines;
-
 	/* The rectangle allocated to this frame, determined by the renderer */
 	double                    x;
 	double                    y;
diff --git a/src/render.c b/src/render.c
index cdf3b0a..1d5656b 100644
--- a/src/render.c
+++ b/src/render.c
@@ -1,7 +1,7 @@
 /*
  * render.c
  *
- * Copyright © 2013-2015 Thomas White <taw@bitwiz.org.uk>
+ * Copyright © 2013-2016 Thomas White <taw@bitwiz.org.uk>
  *
  * This file is part of Colloquium.
  *
@@ -42,6 +42,7 @@
 #include "render.h"
 #include "wrap.h"
 #include "imagestore.h"
+#include "boxvec.h"
 
 
 static void render_glyph_box(cairo_t *cr, struct wrap_box *box)
@@ -197,18 +198,18 @@ static void render_boxes(struct wrap_line *line, cairo_t *cr, ImageStore *is,
 	int j;
 	double x_pos = 0.0;
 
-	for ( j=0; j<line->n_boxes; j++ ) {
+	for ( j=0; j<bv_len(line->boxes); j++ ) {
 
 		struct wrap_box *box;
 
 		cairo_save(cr);
 
-		box = &line->boxes[j];
+		box = bv_box(line->boxes, j);
 		cairo_translate(cr, x_pos, 0.0);
 
 		//draw_outline(cr, box);
 
-		switch ( line->boxes[j].type ) {
+		switch ( box->type ) {
 
 			case WRAP_BOX_PANGO :
 			render_glyph_box(cr, box);
@@ -231,8 +232,8 @@ static void render_boxes(struct wrap_line *line, cairo_t *cr, ImageStore *is,
 
 		}
 
-		x_pos += pango_units_to_double(line->boxes[j].width);
-		x_pos += pango_units_to_double(line->boxes[j].sp);
+		x_pos += pango_units_to_double(box->width);
+		x_pos += pango_units_to_double(box->sp);
 
 		cairo_restore(cr);
 
diff --git a/src/sc_editor.c b/src/sc_editor.c
index 48235c2..e5946ed 100644
--- a/src/sc_editor.c
+++ b/src/sc_editor.c
@@ -1,7 +1,7 @@
 /*
  * sc_editor.c
  *
- * Copyright © 2013-2015 Thomas White <taw@bitwiz.org.uk>
+ * Copyright © 2013-2016 Thomas White <taw@bitwiz.org.uk>
  *
  * This file is part of Colloquium.
  *
@@ -44,6 +44,7 @@
 #include "sc_editor.h"
 #include "slideshow.h"
 #include "shape.h"
+#include "boxvec.h"
 
 
 static void scroll_interface_init(GtkScrollable *iface)
@@ -364,7 +365,7 @@ static void move_cursor_back(SCEditor *e)
 	cl = e->cursor_line;
 
 	line = &e->cursor_frame->lines[e->cursor_line];
-	box = &line->boxes[e->cursor_box];
+	box = bv_box(line->boxes, e->cursor_box);
 	if ( box->type == WRAP_BOX_PANGO ) {
 
 		if ( cp == 0 ) {
@@ -389,13 +390,13 @@ static void move_cursor_back(SCEditor *e)
 				if ( cl < 0 ) return;
 				e->cursor_line = cl;
 				line = &e->cursor_frame->lines[cl];
-				cb = line->n_boxes - 1;
+				cb = bv_len(line->boxes) - 1;
 			}
 
-		} while ( !line->boxes[cb].editable );
+		} while ( !bv_box(line->boxes, cb)->editable );
 
 		e->cursor_box = cb;
-		box = &line->boxes[cb];
+		box = bv_box(line->boxes, cb);
 		if ( box->type == WRAP_BOX_PANGO ) {
 			cp = box->len_chars;
 			if ( box->space == WRAP_SPACE_NONE ) {
@@ -420,11 +421,10 @@ void cur_box_diag(SCEditor *e)
 	sbx = e->cursor_box;
 	sps = e->cursor_pos;
 
-	struct wrap_box *sbox = &fr->lines[sln].boxes[sbx];
+	struct wrap_box *sbox = bv_box(fr->lines[sln].boxes, sbx);
 
 	printf("line/box/pos: [%i of %i]/[%i of %i]/[%i of %i]\n",
-	       sln, fr->n_lines,
-	       sbx, e->cursor_frame->lines[sln].n_boxes,
+	       sln, fr->n_lines, sbx, bv_len(e->cursor_frame->lines[sln].boxes),
 	       sps, sbox->len_chars);
 	printf("box type is %i, space type is %i\n", sbox->type, sbox->space);
 	if ( sbox->type == WRAP_BOX_NOTHING ) {
@@ -433,10 +433,10 @@ void cur_box_diag(SCEditor *e)
 
 	struct wrap_line *ln = &fr->lines[sln];
 	int i;
-	for ( i=0; i<ln->n_boxes; i++ ) {
+	for ( i=0; i<bv_len(ln->boxes); i++ ) {
 		char pp = '[';
 		char pq = ']';
-		struct wrap_box *bx = &ln->boxes[i];
+		struct wrap_box *bx = bv_box(ln->boxes, i);
 		if ( i == sbx ) { pp = '<'; pq  = '>'; }
 		printf("%c%i %i %i%c", pp, bx->offs_char, bx->len_chars,
 		       bx->n_segs, pq);
@@ -450,7 +450,7 @@ void advance_cursor(SCEditor *e)
 	int advance = 0;
 	signed int cp, cb, cl;
 	struct wrap_line *line = &e->cursor_frame->lines[e->cursor_line];
-	struct wrap_box *box = &line->boxes[e->cursor_box];
+	struct wrap_box *box = bv_box(line->boxes, e->cursor_box);
 
 	cp = e->cursor_pos;
 	cb = e->cursor_box;
@@ -493,7 +493,7 @@ void advance_cursor(SCEditor *e)
 				cp = 1;
 			}
 
-			if ( cb >= line->n_boxes ) {
+			if ( cb >= bv_len(line->boxes) ) {
 				cl++;
 				if ( cl >= e->cursor_frame->n_lines ) {
 					/* Give up - could not move */
@@ -504,7 +504,7 @@ void advance_cursor(SCEditor *e)
 				cp = 0;
 			}
 
-		} while ( !line->boxes[cb].editable );
+		} while ( !bv_box(line->boxes, cb)->editable );
 
 		e->cursor_line = cl;
 		e->cursor_box = cb;
@@ -564,7 +564,7 @@ static void draw_caret(cairo_t *cr, struct frame *fr,
 	if ( fr->n_lines == 0 ) return;
 
 	/* Locate the cursor in a "logical" and "geographical" sense */
-	box = &fr->lines[cursor_line].boxes[cursor_box];
+	box = bv_box(fr->lines[cursor_line].boxes, cursor_box);
 	get_cursor_pos(box, cursor_pos, &xposd, &yposd, &line_height);
 	xposd += fr->pad_l;
 	yposd += fr->pad_t;
@@ -574,8 +574,8 @@ static void draw_caret(cairo_t *cr, struct frame *fr,
 	}
 
 	for ( i=0; i<cursor_box; i++ ) {
-		int w = fr->lines[cursor_line].boxes[i].width;
-		w += fr->lines[cursor_line].boxes[i].sp;
+		int w = bv_box(fr->lines[cursor_line].boxes, i)->width;
+		w += bv_box(fr->lines[cursor_line].boxes, i)->sp;
 		xposd += pango_units_to_double(w);
 	}
 
@@ -717,12 +717,12 @@ static void fixup_cursor(SCEditor *e)
 	if ( e->cursor_line >= fr->n_lines ) {
 		/* We find ourselves on a line which doesn't exist */
 		e->cursor_line = fr->n_lines-1;
-		e->cursor_box = fr->lines[fr->n_lines-1].n_boxes-1;
+		e->cursor_box = bv_len(fr->lines[fr->n_lines-1].boxes)-1;
 	}
 
 	sline = &fr->lines[e->cursor_line];
 
-	if ( e->cursor_box >= sline->n_boxes ) {
+	if ( e->cursor_box >= bv_len(sline->boxes) ) {
 
 		/* We find ourselves in a box which doesn't exist */
 
@@ -736,12 +736,12 @@ static void fixup_cursor(SCEditor *e)
 			/* There are no more lines, so just go to the end */
 			e->cursor_line = fr->n_lines-1;
 			sline = &e->cursor_frame->lines[e->cursor_line];
-			e->cursor_box = sline->n_boxes-1;
+			e->cursor_box = bv_len(sline->boxes)-1;
 		}
 	}
 
-	assert(e->cursor_box < sline->n_boxes);
-	sbox = &sline->boxes[e->cursor_box];
+	assert(e->cursor_box < bv_len(sline->boxes));
+	sbox = bv_box(sline->boxes, e->cursor_box);
 
 	if ( e->cursor_pos > sbox->len_chars ) {
 		advance_cursor(e);
@@ -773,7 +773,7 @@ void insert_scblock(SCBlock *scblock, SCEditor *e)
 	sln = e->cursor_line;
 	sbx = e->cursor_box;
 	sps = e->cursor_pos;
-	sbox = &e->cursor_frame->lines[sln].boxes[sbx];
+	sbox = bv_box(e->cursor_frame->lines[sln].boxes, sbx);
 
 	sc_insert_block(sbox->scblock, sps+sbox->offs_char, scblock);
 
@@ -791,17 +791,11 @@ void insert_scblock(SCBlock *scblock, SCEditor *e)
  * Update the boxes from the StoryCode */
 static void update_local(SCEditor *e, struct frame *fr, int line, int bn)
 {
-	struct wrap_box *box = &fr->lines[line].boxes[bn];
+	struct wrap_box *box = bv_box(fr->lines[line].boxes, bn);
 
 	/* Shape the box again
 	 * FIXME: Number of segments could change, need to PangoAnalyse again */
-	shape_box(box->cf->cf);
-
-	/* Update the segments */
-	box->segs = box->cf->cf->segs;
-	box->n_segs = box->cf->cf->n_segs;
-	box->cf->segs = box->cf->cf->segs;
-	box->cf->n_segs = box->cf->cf->n_segs;
+	shape_box(box);
 
 	/* Wrap the paragraph again */
 	wrap_contents(fr);  /* FIXME: Only the current paragraph */
@@ -817,7 +811,7 @@ static void shift_box_offsets(struct frame *fr, struct wrap_box *box, int n)
 	int sn = 0;
 
 	for ( i=0; i<fr->boxes->n_boxes; i++ ) {
-		if ( &fr->boxes->boxes[i] == box ) {
+		if ( bv_box(fr->boxes, i) == box ) {
 			sn = i+1;
 			break;
 		}
@@ -826,7 +820,7 @@ static void shift_box_offsets(struct frame *fr, struct wrap_box *box, int n)
 	assert(sn > 0);  /* Lowest it can possibly be is 1 */
 
 	for ( i=sn; i<fr->boxes->n_boxes; i++ ) {
-		fr->boxes->boxes[i].offs_char += n;
+		bv_box(fr->boxes, i)->offs_char += n;
 	}
 }
 
@@ -851,10 +845,10 @@ static void insert_text(char *t, SCEditor *e)
 	sln = e->cursor_line;
 	sbx = e->cursor_box;
 	sps = e->cursor_pos;
-	sbox = &e->cursor_frame->lines[sln].boxes[sbx];
+	sbox = bv_box(e->cursor_frame->lines[sln].boxes, sbx);
 
 	if ( sbox->type == WRAP_BOX_NOTHING ) {
-		printf("Upgrading nothing box to Pango box\n");
+		printf("Upgrading nothing box %p to Pango box\n", sbox);
 		sbox->type = WRAP_BOX_PANGO;
 		sbox->col[0] = 0.0;
 		sbox->col[1] = 0.0;
@@ -899,7 +893,7 @@ static void insert_text(char *t, SCEditor *e)
 
 		/* Add a new box containing the text after the break */
 		insert_box(&e->cursor_frame->lines[sln], sbx);
-		nbox = &e->cursor_frame->lines[sln].boxes[sbx];
+		nbox = bv_box(e->cursor_frame->lines[sln].boxes, sbx);
 		nbox->type = WRAP_BOX_PANGO;
 		nbox->space = WRAP_SPACE_INTERWORD;
 		nbox->len_chars = e->cursor_pos;
@@ -916,15 +910,8 @@ static void insert_text(char *t, SCEditor *e)
 
 	sbox->segs[sseg].len_chars += 1;
 
-	/* Update the length of the box in the unwrapped and un-paragraph-split
-	 * string of wrap boxes */
-	sbox->cf->cf->len_chars += 1;
-
-	/* ... and also in the paragraph split but unwrapped box */
-	sbox->cf->len_chars += 1;
-
 	/* Tweak the offsets of all the subsequent boxes */
-	shift_box_offsets(fr, sbox->cf->cf, 1);
+	shift_box_offsets(fr, sbox, 1);
 
 	fr->empty = 0;
 
@@ -949,7 +936,7 @@ static void do_backspace(struct frame *fr, SCEditor *e)
 	sln = e->cursor_line;
 	sbx = e->cursor_box;
 	sps = e->cursor_pos;
-	struct wrap_box *sbox = &e->cursor_frame->lines[sln].boxes[sbx];
+	struct wrap_box *sbox = bv_box(e->cursor_frame->lines[sln].boxes, sbx);
 
 	cur_box_diag(e);
 
@@ -957,7 +944,7 @@ static void do_backspace(struct frame *fr, SCEditor *e)
 
 	/* Delete may cross wrap boxes and maybe SCBlock boundaries */
 	struct wrap_line *fline = &e->cursor_frame->lines[e->cursor_line];
-	struct wrap_box *fbox = &fline->boxes[e->cursor_box];
+	struct wrap_box *fbox = bv_box(fline->boxes, e->cursor_box);
 
 //	SCBlock *scbl = sbox->scblock;
 //	do {
@@ -975,15 +962,8 @@ static void do_backspace(struct frame *fr, SCEditor *e)
 //		scbl = sc_block_next(scbl);
 //	} while ( (scbl != fbox->scblock) && (scbl != NULL) );
 
-	/* Update the length of the box in the unwrapped and un-paragraph-split
-	 * string of wrap boxes */
-	sbox->cf->cf->len_chars -= 1;
-
-	/* ... and also in the paragraph split but unwrapped box */
-	sbox->cf->len_chars -= 1;
-
 	/* Tweak the offsets of all the subsequent boxes */
-	shift_box_offsets(fr, sbox->cf->cf, -1);
+	shift_box_offsets(fr, sbox, -1);
 
 	update_local(e, fr, sln, sbx);
 
@@ -1186,7 +1166,7 @@ static void calculate_box_size(struct frame *fr, SCEditor *e,
 
 static struct wrap_box *cbox(struct frame *fr, int ln, int bn)
 {
-	return &fr->lines[ln].boxes[bn];
+	return bv_box(fr->lines[ln].boxes, bn);;
 }
 
 
diff --git a/src/shape.c b/src/shape.c
index 3664780..59ec024 100644
--- a/src/shape.c
+++ b/src/shape.c
@@ -33,6 +33,7 @@
 #include "wrap.h"
 #include "sc_interp.h"
 #include "shape.h"
+#include "boxvec.h"
 
 
 static void shape_segment(struct wrap_box *box, struct text_seg *seg)
@@ -93,19 +94,17 @@ void shape_box(struct wrap_box *box)
 }
 
 
-static void add_nothing_box(struct wrap_line *line, SCBlock *scblock,
+static void add_nothing_box(struct boxvec *boxes, SCBlock *scblock,
                             int editable, enum wrap_box_space sp,
                             SCInterpreter *scin, size_t offs)
 {
 	struct wrap_box *box;
 
-	if ( line->n_boxes == line->max_boxes ) {
-		line->max_boxes += 32;
-		alloc_boxes(line);
-		if ( line->n_boxes == line->max_boxes ) return;
+	box = calloc(1, sizeof(struct wrap_box));
+	if ( box == NULL ) {
+		fprintf(stderr, "Failed to allocate a nothing box.\n");
+		return;
 	}
-
-	box = &line->boxes[line->n_boxes];
 	box->type = WRAP_BOX_NOTHING;
 	box->scblock = scblock;
 	box->offs_char = offs;
@@ -118,7 +117,7 @@ static void add_nothing_box(struct wrap_line *line, SCBlock *scblock,
 	box->editable = editable;
 	box->segs = NULL;
 	box->n_segs = 0;
-	line->n_boxes++;
+	bv_add(boxes, box);
 }
 
 
@@ -185,7 +184,7 @@ static void add_seg(gpointer vi, gpointer vb)
 
 
 /* Add "text", followed by a space of type "space", to "line" */
-static int add_text_box(struct wrap_line *line,
+static int add_text_box(struct boxvec *boxes,
                         enum wrap_box_space space, PangoContext *pc,
                         SCInterpreter *scin, SCBlock *bl, size_t offs,
                         size_t len, int editable)
@@ -199,17 +198,16 @@ static int add_text_box(struct wrap_line *line,
 	int nseg;
 
 	while ( len==0 ) {
-		add_nothing_box(line, bl, editable, space, scin, offs);
+		add_nothing_box(boxes, bl, editable, space, scin, offs);
 		return 0;
 	}
 
 	/* Create the box */
-	if ( line->n_boxes == line->max_boxes ) {
-		line->max_boxes += 32;
-		alloc_boxes(line);
-		if ( line->n_boxes == line->max_boxes ) return 1;
+	box = calloc(1, sizeof(struct wrap_box));
+	if ( box == NULL ) {
+		fprintf(stderr, "Failed to allocate a text box.\n");
+		return 1;
 	}
-	box = &line->boxes[line->n_boxes];
 
 	box->type = WRAP_BOX_PANGO;
 	box->space = space;
@@ -218,7 +216,6 @@ static int add_text_box(struct wrap_line *line,
 	box->editable = editable;
 	box->ascent = sc_interp_get_ascent(scin);
 	box->height = sc_interp_get_height(scin);
-	box->cf = NULL;
 
 	/* Link to the actual text */
 	box->scblock = bl;
@@ -248,24 +245,23 @@ static int add_text_box(struct wrap_line *line,
 
 	calc_box_geometry(box);
 
-	line->n_boxes++;
+	bv_add(boxes, box);
 
 	return 0;
 }
 
 
-void add_callback_box(struct wrap_line *line, double w, double h,
+void add_callback_box(struct boxvec *boxes, double w, double h,
                       SCCallbackDrawFunc draw_func,
                       SCCallbackClickFunc click_func, void *bvp, void *vp)
 {
 	struct wrap_box *box;
 
-	if ( line->n_boxes == line->max_boxes ) {
-		line->max_boxes += 32;
-		alloc_boxes(line);
-		if ( line->n_boxes == line->max_boxes ) return;
+	box = calloc(1, sizeof(struct wrap_box));
+	if ( box == NULL ) {
+		fprintf(stderr, "Failed to allocate a callback box.\n");
+		return;
 	}
-	box = &line->boxes[line->n_boxes];
 
 	box->type = WRAP_BOX_CALLBACK;
 	box->scblock = NULL;
@@ -279,22 +275,21 @@ void add_callback_box(struct wrap_line *line, double w, double h,
 	box->bvp = bvp;
 	box->vp = vp;
 	box->editable = 0;
-	line->n_boxes++;
+	bv_add(boxes, box);
 }
 
 
-void add_image_box(struct wrap_line *line, const char *filename,
+void add_image_box(struct boxvec *boxes, const char *filename,
                    int w, int h, int editable)
 {
 	struct wrap_box *box;
 
-	if ( line->n_boxes == line->max_boxes ) {
-		line->max_boxes += 32;
-		alloc_boxes(line);
-		if ( line->n_boxes == line->max_boxes ) return;
+	box = calloc(1, sizeof(struct wrap_box));
+	if ( box == NULL ) {
+		fprintf(stderr, "Failed to allocate a callback box.\n");
+		return;
 	}
 
-	box = &line->boxes[line->n_boxes];
 	box->type = WRAP_BOX_IMAGE;
 	box->scblock = NULL;
 	box->offs_char = 0;
@@ -304,11 +299,11 @@ void add_image_box(struct wrap_line *line, const char *filename,
 	box->height = pango_units_from_double(h);
 	box->filename = strdup(filename);
 	box->editable = editable;
-	line->n_boxes++;
+	bv_add(boxes, box);
 }
 
 
-int split_words(struct wrap_line *boxes, PangoContext *pc, SCBlock *bl,
+int split_words(struct boxvec *boxes, PangoContext *pc, SCBlock *bl,
                 PangoLanguage *lang, int editable, SCInterpreter *scin)
 {
 	PangoLogAttr *log_attrs;
diff --git a/src/shape.h b/src/shape.h
index b9a5191..43775a3 100644
--- a/src/shape.h
+++ b/src/shape.h
@@ -33,14 +33,14 @@
 
 extern void shape_box(struct wrap_box *box);
 
-extern int split_words(struct wrap_line *boxes, PangoContext *pc,
+extern int split_words(struct boxvec *boxes, PangoContext *pc,
                        SCBlock *bl, PangoLanguage *lang,
                        int editable, SCInterpreter *scin);
 
-extern void add_image_box(struct wrap_line *line, const char *filename,
+extern void add_image_box(struct boxvec *line, const char *filename,
                           int w, int h, int editable);
 
-extern void add_callback_box(struct wrap_line *line, double w, double h,
+extern void add_callback_box(struct boxvec *boxes, double w, double h,
                              SCCallbackDrawFunc draw_func,
                              SCCallbackClickFunc click_func,
                              void *bvp, void *vp);
diff --git a/src/wrap.c b/src/wrap.c
index fa383b3..9fc233f 100644
--- a/src/wrap.c
+++ b/src/wrap.c
@@ -3,7 +3,7 @@
  *
  * Text wrapping, hyphenation, justification etc
  *
- * Copyright © 2013-2015 Thomas White <taw@bitwiz.org.uk>
+ * Copyright © 2013-2016 Thomas White <taw@bitwiz.org.uk>
  *
  * This file is part of Colloquium.
  *
@@ -39,6 +39,7 @@
 #include "wrap.h"
 #include "frame.h"
 #include "presentation.h"
+#include "boxvec.h"
 
 
 static void alloc_lines(struct frame *fr)
@@ -55,32 +56,14 @@ static void alloc_lines(struct frame *fr)
 }
 
 
-int alloc_boxes(struct wrap_line *l)
-{
-	struct wrap_box *boxes_new;
-
-	boxes_new = realloc(l->boxes, l->max_boxes * sizeof(struct wrap_box));
-	if ( boxes_new == NULL ) {
-		fprintf(stderr, "Couldn't allocate memory for boxes!\n");
-		return 1;
-	}
-
-	l->boxes = boxes_new;
-	return 0;
-}
-
-
 void initialise_line(struct wrap_line *l)
 {
-	l->n_boxes = 0;
-	l->max_boxes = 32;
-	l->boxes = NULL;
 	l->width = 0;
 	l->height = 0;
 	l->ascent = 0;
 	l->last_line = 0;
 	l->overfull = 0;
-	alloc_boxes(l);
+	l->boxes = bv_new();
 }
 
 
@@ -255,9 +238,9 @@ static int find_cursor_box(struct frame *fr, struct wrap_line *l,
 
 	*end = 0;
 
-	for ( i=0; i<l->n_boxes; i++ ) {
-		double width = pango_units_to_double(l->boxes[i].width);
-		width += pango_units_to_double(l->boxes[i].sp);
+	for ( i=0; i<l->boxes->n_boxes; i++ ) {
+		double width = pango_units_to_double(bv_box(l->boxes, i)->width);
+		width += pango_units_to_double(bv_box(l->boxes, i)->sp);
 		if ( xposd < x + width ) {
 			*x_pos = xposd - x;
 			return i;
@@ -267,7 +250,7 @@ static int find_cursor_box(struct frame *fr, struct wrap_line *l,
 
 	*end = 1;
 	*x_pos = x;
-	return l->n_boxes-1;
+	return bv_len(l->boxes)-1;
 }
 
 
@@ -297,11 +280,11 @@ void find_cursor(struct frame *fr, double xposd, double yposd,
 	*line = ln;
 
 	if ( end ) {
-		bn = l->n_boxes-1;
+		bn = l->boxes->n_boxes-1;
 	} else {
 		bn = find_cursor_box(fr, l, xposd, &x_pos, &end);
 	}
-	b = &l->boxes[bn];
+	b = bv_box(l->boxes, bn);
 	*box = bn;
 	if ( end ) {
 		*pos = b->len_chars;
@@ -363,9 +346,9 @@ static void calc_line_geometry(struct wrap_line *line)
 	line->ascent = 0;
 	line->height = 0;
 
-	for ( i=0; i<line->n_boxes; i++ ) {
+	for ( i=0; i<line->boxes->n_boxes; i++ ) {
 
-		struct wrap_box *box = &line->boxes[i];
+		struct wrap_box *box = bv_box(line->boxes, i);
 
 		line->width += box->width;
 		if ( box->space == WRAP_SPACE_EOP ) box->sp = 0.0;
@@ -476,19 +459,19 @@ static void consider_break(double sigma_prime, double sigma_prime_max,
 }
 
 
-static double width(struct wrap_line *boxes, int i)
+static double width(struct boxvec *boxes, int i)
 {
 	/* Indices in Knuth paper go from 1...n.  Indices in array go
 	 * from 0...n-1 */
-	return boxes->boxes[i-1].width;
+	return bv_box(boxes, i-1)->width;
 }
 
 
-static enum wrap_box_space space(struct wrap_line *boxes, int i)
+static enum wrap_box_space space(struct boxvec *boxes, int i)
 {
 	/* Indices in Knuth paper go from 1...n.  Indices in array go
 	 * from 0...n-1 */
-	return boxes->boxes[i-1].space;
+	return bv_box(boxes, i-1)->space;
 }
 
 
@@ -503,13 +486,13 @@ static void UNUSED distribute_spaces(struct wrap_line *line, double l,
 	l = pango_units_from_double(l);
 
 	L = 0.0;  Y = 0.0;  Z = 0.0;
-	for ( i=0; i<line->n_boxes-1; i++ ) {
-		L += line->boxes[i].width;
-		L += sp_x(line->boxes[i].space);
-		Y += sp_y(line->boxes[i].space);
-		Z += sp_z(line->boxes[i].space);
+	for ( i=0; i<bv_len(line->boxes); i++ ) {
+		L += bv_box(line->boxes, i)->width;
+		L += sp_x(bv_box(line->boxes, i)->space);
+		Y += sp_y(bv_box(line->boxes, i)->space);
+		Z += sp_z(bv_box(line->boxes, i)->space);
 	}
-	L += line->boxes[line->n_boxes-1].width;
+	L += bv_last(line->boxes)->width;
 
 	if ( L < l ) {
 		r = (l - L)/Y;
@@ -520,24 +503,24 @@ static void UNUSED distribute_spaces(struct wrap_line *line, double l,
 	}
 
 	if ( r >= 0.0 ) {
-		for ( i=0; i<line->n_boxes-1; i++ ) {
-			line->boxes[i].sp = sp_x(line->boxes[i].space);
-			line->boxes[i].sp += r*sp_y(line->boxes[i].space);
+		for ( i=0; i<bv_len(line->boxes)-1; i++ ) {
+			bv_box(line->boxes, i)->sp = sp_x(bv_box(line->boxes, i)->space);
+			bv_box(line->boxes, i)->sp += r*sp_y(bv_box(line->boxes, i)->space);
 		}
 	} else {
-		for ( i=0; i<line->n_boxes-1; i++ ) {
-			line->boxes[i].sp = sp_x(line->boxes[i].space);
-			line->boxes[i].sp += r*sp_z(line->boxes[i].space);
+		for ( i=0; bv_len(line->boxes)-1; i++ ) {
+			bv_box(line->boxes, i)->sp = sp_x(bv_box(line->boxes, i)->space);
+			bv_box(line->boxes, i)->sp += r*sp_z(bv_box(line->boxes, i)->space);
 		}
 	}
 
-	line->boxes[line->n_boxes-1].sp = 0.0;
+	bv_box(line->boxes, bv_len(line->boxes)-1)->sp = 0.0;
 	line->overfull = overfull;
 	line->underfull = underfull;
 }
 
 
-static void output_line(int q, int s, struct frame *fr, struct wrap_line *boxes)
+static void output_line(int q, int s, struct frame *fr, struct boxvec *boxes)
 {
 	struct wrap_line *l;
 	int j;
@@ -546,16 +529,14 @@ static void output_line(int q, int s, struct frame *fr, struct wrap_line *boxes)
 	fr->n_lines++;
 	initialise_line(l);
 
-	l->max_boxes = s-q;
-	alloc_boxes(l);
+	bv_ensure_space(l->boxes, s-q);
 	for ( j=q; j<s; j++ ) {
-		l->boxes[l->n_boxes++] = boxes->boxes[j];
+		bv_add(l->boxes, bv_box(boxes, j));
 	}
 }
 
 
-static void output(int a, int i, int *p, struct frame *fr,
-                   struct wrap_line *boxes)
+static void output(int a, int i, int *p, struct frame *fr, struct boxvec *boxes)
 {
 	int q = i;
 	int r;
@@ -590,7 +571,7 @@ static void output(int a, int i, int *p, struct frame *fr,
  * Practice and Experience 11 (1981) p1119-1184.  Despite the name, it's
  * supposed to work as well as the full TeX algorithm in almost all of the cases
  * that we care about here. */
-static void UNUSED knuth_suboptimal_fit(struct wrap_line *boxes,
+static void UNUSED knuth_suboptimal_fit(struct boxvec *boxes,
                                         double line_length, struct frame *fr,
                                         double rho)
 {
@@ -607,15 +588,14 @@ static void UNUSED knuth_suboptimal_fit(struct wrap_line *boxes,
 	n = boxes->n_boxes;
 
 	/* Set the space for the last box to be "end of paragraph" */
-	boxes->boxes[boxes->n_boxes-1].space = WRAP_SPACE_EOP;
+	bv_last(boxes)->space = WRAP_SPACE_EOP;
 
 	/* Add empty zero-width box at end */
-	if ( boxes->n_boxes == boxes->max_boxes ) {
-		boxes->max_boxes += 32;
-		alloc_boxes(boxes);
-		if ( boxes->n_boxes == boxes->max_boxes ) return;
+	box = malloc(sizeof(struct wrap_box));
+	if ( box== NULL ) {
+		fprintf(stderr, "Couldn't allocate sentinel box\n");
+		return;
 	}
-	box = &boxes->boxes[boxes->n_boxes];
 	box->type = WRAP_BOX_SENTINEL;
 	box->space = WRAP_SPACE_NONE;
 	box->font = NULL;
@@ -625,15 +605,15 @@ static void UNUSED knuth_suboptimal_fit(struct wrap_line *boxes,
 	box->editable = 1;
 	box->scblock = NULL;
 	box->offs_char = 0;
-	boxes->n_boxes++;
+	bv_add(boxes, box);
 
 	line_length *= PANGO_SCALE;
 
 	reject = 0;
-	for ( j=0; j<boxes->n_boxes; j++ ) {
-		if ( boxes->boxes[j].width > line_length ) {
+	for ( j=0; j<bv_len(boxes); j++ ) {
+		if ( bv_box(boxes, j)->width > line_length ) {
 			fprintf(stderr, "ERROR: Box %i too long (%i %f)\n", j,
-			                boxes->boxes[j].width, line_length);
+			                bv_box(boxes, j)->width, line_length);
 			fr->trouble = 1;
 			reject = 1;
 		}
@@ -772,6 +752,7 @@ static void UNUSED knuth_suboptimal_fit(struct wrap_line *boxes,
 
 	free(p);
 	free(s);
+	free(box);  /* The sentinel box */
 }
 
 
@@ -792,16 +773,7 @@ static struct wrap_line *new_line(struct frame *fr)
 }
 
 
-static int maybe_extend_line(struct wrap_line *l)
-{
-	if ( l->n_boxes < l->max_boxes ) return 0;
-
-	l->max_boxes += 32;
-	return alloc_boxes(l);
-}
-
-
-static void first_fit(struct wrap_line *boxes, double line_length,
+static void first_fit(struct boxvec *boxes, double line_length,
                       struct frame *fr)
 {
 	struct wrap_line *line;
@@ -815,23 +787,20 @@ static void first_fit(struct wrap_line *boxes, double line_length,
 
 	do {
 
-		boxes->boxes[j].sp = sp_x(boxes->boxes[j].space);
+		bv_box(boxes, j)->sp = sp_x(bv_box(boxes, j)->space);
 
-		len += boxes->boxes[j].width;
+		len += bv_box(boxes, j)->width;
 
 		if ( len > line_length ) {
 			line = new_line(fr);
-			len = boxes->boxes[j].width;
+			len = bv_box(boxes, j)->width;
 		}
-		line->boxes[line->n_boxes] = boxes->boxes[j];
-		line->boxes[line->n_boxes].cf = &boxes->boxes[j];
-		line->n_boxes++;
-		if ( maybe_extend_line(line) ) return;
+		bv_add(line->boxes, bv_box(boxes, j));
 		j++;
 
-		if ( (j > 0) && (boxes->boxes[j-1].type != WRAP_BOX_SENTINEL) )
+		if ( (j > 0) && (bv_box(boxes, j-1)->type != WRAP_BOX_SENTINEL) )
 		{
-			len += sp_x(boxes->boxes[j-1].space);
+			len += sp_x(bv_box(boxes, j-1)->space);
 		}
 
 	} while ( j < boxes->n_boxes );
@@ -842,66 +811,35 @@ static void first_fit(struct wrap_line *boxes, double line_length,
 
 void wrap_line_free(struct wrap_line *l)
 {
-	int i, j;
-	for ( i=0; i<l->n_boxes; i++ ) {
-
-		switch ( l->boxes[i].type ) {
-
-			case WRAP_BOX_PANGO :
-			for ( j=0; j<l->boxes[i].n_segs; j++ ) {
-				pango_glyph_string_free(l->boxes[i].segs[j].glyphs);
-			}
-			free(l->boxes[i].segs);
-			break;
-
-			case WRAP_BOX_IMAGE :
-			break;
-
-			case WRAP_BOX_CALLBACK :
-			break;
-
-			case WRAP_BOX_NOTHING :
-			case WRAP_BOX_SENTINEL :
-			break;
-
-		}
-
-	}
-
+	bv_free(l->boxes);
 	free(l->boxes);
 }
 
 
-static struct wrap_line *split_paragraph(struct wrap_line *boxes, int *n,
-                                         int *eop)
+static struct boxvec *split_paragraph(struct boxvec *boxes, int *n, int *eop)
 {
 	int i;
 	int start = *n;
 	int end;
 
-	if ( start >= boxes->n_boxes ) return NULL;
+	if ( start >= bv_len(boxes) ) return NULL;
 
 	*eop = 0;
-	for ( i=start; i<boxes->n_boxes; i++ ) {
-		if ( boxes->boxes[i].space == WRAP_SPACE_EOP ) {
+	for ( i=start; i<bv_len(boxes); i++ ) {
+		if ( bv_box(boxes, i)->space == WRAP_SPACE_EOP ) {
 			*eop = 1;
 			break;
 		}
 	}
 	end = i + 1;
 	*n = end;
-	if ( i == boxes->n_boxes ) end--;
+	if ( i == bv_len(boxes) ) end--;
 
 	if ( end-start > 0 ) {
-		struct wrap_line *para;
-		para = malloc(sizeof(struct wrap_line));
-		para->boxes = NULL;
-		para->max_boxes = end-start;
-		para->n_boxes = end-start;
-		alloc_boxes(para);
+		struct boxvec *para = bv_new();
+		bv_ensure_space(para, end-start);
 		for ( i=start; i<end; i++ ) {
-			para->boxes[i-start] = boxes->boxes[i];
-			para->boxes[i-start].cf = &boxes->boxes[i];
+			bv_add(para, bv_box(boxes, i));
 		}
 		return para;
 	}
@@ -910,7 +848,7 @@ static struct wrap_line *split_paragraph(struct wrap_line *boxes, int *n,
 }
 
 
-void show_boxes(struct wrap_line *boxes)
+void show_boxes(struct boxvec *boxes)
 {
 	int i;
 
@@ -919,8 +857,8 @@ void show_boxes(struct wrap_line *boxes)
 		return;
 	}
 
-	for ( i=0; i<boxes->n_boxes; i++ ) {
-		struct wrap_box *box = &boxes->boxes[i];
+	for ( i=0; i<bv_len(boxes); i++ ) {
+		struct wrap_box *box = bv_box(boxes, i);
 		char *box_text;
 		printf("%3i", i);
 		if ( box->scblock != NULL ) {
@@ -971,7 +909,7 @@ static int wrap_everything(struct frame *fr, double wrap_w)
  * and generate fr->lines */
 int wrap_contents(struct frame *fr)
 {
-	struct wrap_line *para;
+	struct boxvec *para;
 	int i, eop = 0;
 	//const double rho = 2.0;
 	const double wrap_w = fr->w - fr->pad_l - fr->pad_r;
@@ -1016,54 +954,6 @@ int wrap_contents(struct frame *fr)
 		return 0;
 	}
 
-	/* If the last paragraph ended with an EOP, add an extra line */
-	if ( eop || (fr->n_lines == 0) ) {
-
-		struct wrap_line *l;
-		struct wrap_box *last_box;
-
-		if ( fr->n_lines > 0 ) {
-			l = &fr->lines[fr->n_lines-1];
-			last_box = &l->boxes[l->n_boxes-1];
-		} else {
-			last_box = NULL;
-		}
-
-		if ( fr->n_lines + 1 > fr->max_lines ) {
-			fr->max_lines += 32;
-			alloc_lines(fr);
-			if ( fr->n_lines == fr->max_lines ) return 1;
-		}
-
-		l = &fr->lines[fr->n_lines];
-		fr->n_lines++;
-		initialise_line(l);
-
-		l->max_boxes = 1;
-		alloc_boxes(l);
-		l->n_boxes = 1;
-		l->boxes[0].type = WRAP_BOX_NOTHING;
-		l->boxes[0].editable = 1;
-		l->boxes[0].space = WRAP_SPACE_NONE;
-
-		if ( last_box != NULL ) {
-			l->boxes[0].scblock = last_box->scblock;
-			l->boxes[0].offs_char = last_box->len_chars
-			                        + last_box->offs_char;
-			l->boxes[0].ascent = last_box->ascent;
-			l->boxes[0].height = last_box->height;
-			l->boxes[0].width = 0;
-			/* FIXME: Get ascent and descent from font metrics for
-			 * whichever font will be used in this box */
-		} else {
-			l->boxes[0].scblock = find_last_child(fr->scblocks);
-			l->boxes[0].offs_char = 0;
-			l->boxes[0].ascent = 10000;
-			l->boxes[0].height = 10000;
-			l->boxes[0].width = 0;
-		}
-	}
-
 	for ( i=0; i<fr->n_lines; i++ ) {
 
 		struct wrap_line *line = &fr->lines[i];
@@ -1071,8 +961,8 @@ int wrap_contents(struct frame *fr)
 		//distribute_spaces(line, wrap_w, rho);
 
 		/* Strip any sentinel boxes added by the wrapping algorithm */
-		if ( line->boxes[line->n_boxes-1].type == WRAP_BOX_SENTINEL ) {
-			line->n_boxes--;
+		if ( bv_last(line->boxes)->type == WRAP_BOX_SENTINEL ) {
+			line->boxes->n_boxes--;
 		}
 
 	}
@@ -1105,6 +995,8 @@ int insert_box(struct wrap_line *l, int pos)
 {
 	int i;
 
+/* FIXME ! */
+#if 0
 	if ( l->n_boxes == l->max_boxes ) {
 		l->max_boxes += 32;
 		if ( alloc_boxes(l) ) return 1;
@@ -1116,6 +1008,8 @@ int insert_box(struct wrap_line *l, int pos)
 	}
 
 	l->n_boxes++;
+#endif
+return 1;
 
 	return 0;
 }
diff --git a/src/wrap.h b/src/wrap.h
index 97dea37..0dcc190 100644
--- a/src/wrap.h
+++ b/src/wrap.h
@@ -3,7 +3,7 @@
  *
  * Text wrapping, hyphenation, justification and shaping
  *
- * Copyright © 2014-2015 Thomas White <taw@bitwiz.org.uk>
+ * Copyright © 2014-2016 Thomas White <taw@bitwiz.org.uk>
  *
  * This file is part of Colloquium.
  *
@@ -81,7 +81,6 @@ struct wrap_box
 
 	SCBlock *scblock;
 	int offs_char;  /* offset (in characters, not bytes) into scblock */
-	struct wrap_box *cf;  /* Copied from */
 
 	/* Pango units */
 	int width;
@@ -109,22 +108,20 @@ struct wrap_box
 };
 
 
+/* An actual wrap line, with geometry etc */
 struct wrap_line
 {
+	struct boxvec *boxes;
+
 	int width;   /* Pango units */
 	int height;  /* Pango units */
 	int ascent;  /* Pango units */
 
-	int n_boxes;
-	int max_boxes;
-	struct wrap_box *boxes;
-
 	int overfull;
 	int underfull;
 	int last_line;
 };
 
-
 extern int wrap_contents(struct frame *fr);
 
 extern void get_cursor_pos(struct wrap_box *box, int pos,
@@ -137,7 +134,7 @@ extern int alloc_boxes(struct wrap_line *l);
 extern void initialise_line(struct wrap_line *l);
 
 extern void wrap_line_free(struct wrap_line *l);
-extern void show_boxes(struct wrap_line *boxes);
+extern void show_boxes(struct boxvec *boxes);
 extern double total_height(struct frame *fr);
 
 extern int insert_box(struct wrap_line *l, int pos);