diff --git a/winio.c b/winio.c
index 71adf291867725f9136ef3032a9a5b1a9d63c163..d58994d5539dbd06c39eea9026c44f40fb3a1d70 100644
--- a/winio.c
+++ b/winio.c
@@ -521,6 +521,10 @@ void set_modified(void)
}
}
+/* And so start the display update routines */
+/* Given a column, this returns the "page" it is on */
+/* "page" in the case of the display columns, means which set of 80 */
+/* characters is viewable (ie: page 1 shows from 1 to COLS) */
inline int get_page_from_virtual(int virtual)
{
int page = 2;
@@ -537,6 +541,7 @@ inline int get_page_from_virtual(int virtual)
return page;
}
+/* The inverse of the above function */
inline int get_page_start_virtual(int page)
{
int virtual;
@@ -552,16 +557,25 @@ inline int get_page_end_virtual(int page)
}
#ifndef NANO_SMALL
-/* Called only from edit_add, and therefore expects a
- * converted-to-only-spaces line */
+/* This takes care of the case where there is a mark that covers only */
+/* the current line. */
+
+/* It expects a line with no tab characers (ie: the type that edit_add
+/* deals with */
void add_marked_sameline(int begin, int end, filestruct * fileptr, int y,
int virt_cur_x, int this_page)
{
+ /*
+ * The general idea is to break the line up into 3 sections: before
+ * the mark, the mark, and after the mark. We then paint each in
+ * turn (for those that are currently visible, of course
+ *
+ * 3 start points: 0 -> begin, begin->end, end->strlen(data)
+ * in data : pre sel post
+ */
int this_page_start = get_page_start_virtual(this_page),
this_page_end = get_page_end_virtual(this_page);
- /* 3 start points: 0 -> begin, begin->end, end->strlen(data) */
- /* in data : pre sel post */
/* likewise, 3 data lengths */
int pre_data_len = begin, sel_data_len = end - begin, post_data_len = 0; /* Determined from the other two */
@@ -578,17 +592,17 @@ void add_marked_sameline(int begin, int end, filestruct * fileptr, int y,
if (end < this_page_start)
end = this_page_start;
- /* we don't care about end, because it will just get cropped
- * due to length */
if (begin > this_page_end)
begin = this_page_end;
if (end > this_page_end)
end = this_page_end;
+ /* Now calculate the lengths */
sel_data_len = end - begin;
post_data_len = this_page_end - end;
+ /* Paint this line! */
mvwaddnstr(edit, y, 0, &fileptr->data[this_page_start], pre_data_len);
wattron(edit, A_REVERSE);
mvwaddnstr(edit, y, begin - this_page_start,
@@ -599,39 +613,57 @@ void add_marked_sameline(int begin, int end, filestruct * fileptr, int y,
}
#endif
-/* Called only from update_line. Expects a converted-to-not-have-tabs
+/* edit_add takes care of the job of actually painting a line into the
+ * edit window.
+ *
+ * Called only from update_line. Expects a converted-to-not-have-tabs
* line */
void edit_add(filestruct * fileptr, int yval, int start, int virt_cur_x,
int virt_mark_beginx, int this_page)
{
#ifndef NANO_SMALL
- if (ISSET(MARK_ISSET)) {
- if ((fileptr->lineno > mark_beginbuf->lineno
+ /* There are quite a few cases that could take place, we'll deal
+ * with them each in turn */
+ if (ISSET(MARK_ISSET)
+ && !((fileptr->lineno > mark_beginbuf->lineno
&& fileptr->lineno > current->lineno)
|| (fileptr->lineno < mark_beginbuf->lineno
- && fileptr->lineno < current->lineno)) {
-
- /* We're on a normal, unselected line */
- mvwaddnstr(edit, yval, 0, fileptr->data, COLS);
- } else {
+ && fileptr->lineno < current->lineno)))
+ {
+ /* If we get here we are on a line that is atleast
+ * partially selected. The lineno checks above determined
+ * that */
if (fileptr != mark_beginbuf && fileptr != current) {
- /* We're on selected text */
+ /* We are on a completely marked line, paint it all
+ * inverse */
wattron(edit, A_REVERSE);
mvwaddnstr(edit, yval, 0, fileptr->data, COLS);
wattroff(edit, A_REVERSE);
} else if (fileptr == mark_beginbuf && fileptr == current) {
/* Special case, we're still on the same line we started
- * marking */
- if (virt_cur_x < virt_mark_beginx)
+ * marking -- so we call our helper function */
+ if (virt_cur_x < virt_mark_beginx) {
+ /* To the right of us is marked */
add_marked_sameline(virt_cur_x, virt_mark_beginx,
fileptr, yval, virt_cur_x,
this_page);
- else
+ } else {
+ /* To the left of us is marked */
add_marked_sameline(virt_mark_beginx, virt_cur_x,
fileptr, yval, virt_cur_x,
this_page);
+ }
} else if (fileptr == mark_beginbuf) {
- /* we're updating the line that was first marked */
+ /*
+ * we're updating the line that was first marked
+ * but we're not currently on it. So we want to
+ * figur out which half to invert based on our
+ * relative line numbers.
+ *
+ * i.e. If we're above the "beginbuf" line, we want to
+ * mark the left side. Otherwise we're below, so we
+ * mark the right
+ */
int target;
if (mark_beginbuf->lineno > current->lineno)
@@ -660,7 +692,7 @@ void edit_add(filestruct * fileptr, int yval, int start, int virt_cur_x,
} else if (fileptr == current) {
/* we're on the cursors line, but it's not the first
- * one we marked... */
+ * one we marked. Similar to the previous logic. */
int this_page_start = get_page_start_virtual(this_page),
this_page_end = get_page_end_virtual(this_page);
@@ -691,17 +723,18 @@ void edit_add(filestruct * fileptr, int yval, int start, int virt_cur_x,
if (mark_beginbuf->lineno > current->lineno)
wattroff(edit, A_REVERSE);
- }
}
} else
#endif
+ /* Just paint the string (no mark on this line) */
mvwaddnstr(edit, yval, 0, &fileptr->data[start],
get_page_end_virtual(this_page) - start);
}
/*
- * Just update one line in the edit buffer
+ * Just update one line in the edit buffer. Basically a wrapper for
+ * edit_add
*
* index gives is a place in the string to update starting from.
* Likely args are current_x or 0.