+/************************************************************************
+ Mouse Highlight (and friends..)
+ ************************************************************************/
+
+/* Last window where we saw the mouse. Used by mouse-autoselect-window. */
+static Lisp_Object last_mouse_window;
+
+static int mouse_preempted = 0; /* non-zero when XMenu gobbles mouse events */
+
+/* Set the mouse pointer shape according to whether it is in the
+ area where the mouse highlight is in effect. */
+static void
+IT_set_mouse_pointer (int mode)
+{
+ /* A no-op for now. DOS text-mode mouse pointer doesn't offer too
+ many possibilities to change its shape, and the available
+ functionality pretty much sucks (e.g., almost every reasonable
+ shape will conceal the character it is on). Since the color of
+ the pointer changes in the highlighted area, it is not clear to
+ me whether anything else is required, anyway. */
+}
+
+/* Display the active region described by mouse_face_*
+ in its mouse-face if HL > 0, in its normal face if HL = 0. */
+static void
+show_mouse_face (struct display_info *dpyinfo, int hl)
+{
+ struct window *w = XWINDOW (dpyinfo->mouse_face_window);
+ struct frame *f = XFRAME (WINDOW_FRAME (w));
+ int i;
+ struct face *fp;
+
+
+ /* If window is in the process of being destroyed, don't bother
+ doing anything. */
+ if (w->current_matrix == NULL)
+ goto set_cursor_shape;
+
+ /* Recognize when we are called to operate on rows that don't exist
+ anymore. This can happen when a window is split. */
+ if (dpyinfo->mouse_face_end_row >= w->current_matrix->nrows)
+ goto set_cursor_shape;
+
+ /* There's no sense to do anything if the mouse face isn't realized. */
+ if (hl > 0)
+ {
+ if (dpyinfo->mouse_face_hidden)
+ goto set_cursor_shape;
+
+ fp = FACE_FROM_ID (SELECTED_FRAME(), dpyinfo->mouse_face_face_id);
+ if (!fp)
+ goto set_cursor_shape;
+ }
+
+ /* Note that mouse_face_beg_row etc. are window relative. */
+ for (i = dpyinfo->mouse_face_beg_row;
+ i <= dpyinfo->mouse_face_end_row;
+ i++)
+ {
+ int start_hpos, end_hpos;
+ struct glyph_row *row = MATRIX_ROW (w->current_matrix, i);
+
+ /* Don't do anything if row doesn't have valid contents. */
+ if (!row->enabled_p)
+ continue;
+
+ /* For all but the first row, the highlight starts at column 0. */
+ if (i == dpyinfo->mouse_face_beg_row)
+ start_hpos = dpyinfo->mouse_face_beg_col;
+ else
+ start_hpos = 0;
+
+ if (i == dpyinfo->mouse_face_end_row)
+ end_hpos = dpyinfo->mouse_face_end_col;
+ else
+ end_hpos = row->used[TEXT_AREA];
+
+ if (end_hpos <= start_hpos)
+ continue;
+ /* Record that some glyphs of this row are displayed in
+ mouse-face. */
+ row->mouse_face_p = hl > 0;
+ if (hl > 0)
+ {
+ int vpos = row->y + WINDOW_TOP_EDGE_Y (w);
+ int kstart = start_hpos + WINDOW_LEFT_EDGE_X (w);
+ int nglyphs = end_hpos - start_hpos;
+ int offset = ScreenPrimary + 2*(vpos*screen_size_X + kstart) + 1;
+ int start_offset = offset;
+
+ if (termscript)
+ fprintf (termscript, "\n<MH+ %d-%d:%d>",
+ kstart, kstart + nglyphs - 1, vpos);
+
+ mouse_off ();
+ IT_set_face (dpyinfo->mouse_face_face_id);
+ /* Since we are going to change only the _colors_ of the
+ displayed text, there's no need to go through all the
+ pain of generating and encoding the text from the glyphs.
+ Instead, we simply poke the attribute byte of each
+ affected position in video memory with the colors
+ computed by IT_set_face! */
+ _farsetsel (_dos_ds);
+ while (nglyphs--)
+ {
+ _farnspokeb (offset, ScreenAttrib);
+ offset += 2;
+ }
+ if (screen_virtual_segment)
+ dosv_refresh_virtual_screen (start_offset, end_hpos - start_hpos);
+ mouse_on ();
+ }
+ else
+ {
+ /* We are removing a previously-drawn mouse highlight. The
+ safest way to do so is to redraw the glyphs anew, since
+ all kinds of faces and display tables could have changed
+ behind our back. */
+ int nglyphs = end_hpos - start_hpos;
+ int save_x = new_pos_X, save_y = new_pos_Y;
+
+ if (end_hpos >= row->used[TEXT_AREA])
+ nglyphs = row->used[TEXT_AREA] - start_hpos;
+
+ /* IT_write_glyphs writes at cursor position, so we need to
+ temporarily move cursor coordinates to the beginning of
+ the highlight region. */
+ new_pos_X = start_hpos + WINDOW_LEFT_EDGE_X (w);
+ new_pos_Y = row->y + WINDOW_TOP_EDGE_Y (w);
+
+ if (termscript)
+ fprintf (termscript, "<MH- %d-%d:%d>",
+ new_pos_X, new_pos_X + nglyphs - 1, new_pos_Y);
+ IT_write_glyphs (row->glyphs[TEXT_AREA] + start_hpos, nglyphs);
+ if (termscript)
+ fputs ("\n", termscript);
+ new_pos_X = save_x;
+ new_pos_Y = save_y;
+ }
+ }
+
+ set_cursor_shape:
+ /* Change the mouse pointer shape. */
+ IT_set_mouse_pointer (hl);
+}
+
+/* Clear out the mouse-highlighted active region.
+ Redraw it un-highlighted first. */
+static void
+clear_mouse_face (struct display_info *dpyinfo)
+{
+ if (!dpyinfo->mouse_face_hidden && ! NILP (dpyinfo->mouse_face_window))
+ show_mouse_face (dpyinfo, 0);
+
+ dpyinfo->mouse_face_beg_row = dpyinfo->mouse_face_beg_col = -1;
+ dpyinfo->mouse_face_end_row = dpyinfo->mouse_face_end_col = -1;
+ dpyinfo->mouse_face_window = Qnil;
+}
+
+/* Find the glyph matrix position of buffer position POS in window W.
+ *HPOS and *VPOS are set to the positions found. W's current glyphs
+ must be up to date. If POS is above window start return (0, 0).
+ If POS is after end of W, return end of last line in W. */
+static int
+fast_find_position (struct window *w, int pos, int *hpos, int *vpos)
+{
+ int i, lastcol, line_start_position, maybe_next_line_p = 0;
+ int yb = window_text_bottom_y (w);
+ struct glyph_row *row = MATRIX_ROW (w->current_matrix, 0), *best_row = row;
+
+ while (row->y < yb)
+ {
+ if (row->used[TEXT_AREA])
+ line_start_position = row->glyphs[TEXT_AREA]->charpos;
+ else
+ line_start_position = 0;
+
+ if (line_start_position > pos)
+ break;
+ /* If the position sought is the end of the buffer,
+ don't include the blank lines at the bottom of the window. */
+ else if (line_start_position == pos
+ && pos == BUF_ZV (XBUFFER (w->buffer)))
+ {
+ maybe_next_line_p = 1;
+ break;
+ }
+ else if (line_start_position > 0)
+ best_row = row;
+
+ /* Don't overstep the last matrix row, lest we get into the
+ never-never land... */
+ if (row->y + 1 >= yb)
+ break;
+
+ ++row;
+ }
+
+ /* Find the right column within BEST_ROW. */
+ lastcol = 0;
+ row = best_row;
+ for (i = 0; i < row->used[TEXT_AREA]; i++)
+ {
+ struct glyph *glyph = row->glyphs[TEXT_AREA] + i;
+ int charpos;
+
+ charpos = glyph->charpos;
+ if (charpos == pos)
+ {
+ *hpos = i;
+ *vpos = row->y;
+ return 1;
+ }
+ else if (charpos > pos)
+ break;
+ else if (charpos > 0)
+ lastcol = i;
+ }
+
+ /* If we're looking for the end of the buffer,
+ and we didn't find it in the line we scanned,
+ use the start of the following line. */
+ if (maybe_next_line_p)
+ {
+ ++row;
+ lastcol = 0;
+ }
+
+ *vpos = row->y;
+ *hpos = lastcol + 1;
+ return 0;
+}
+
+/* Take proper action when mouse has moved to the mode or top line of
+ window W, x-position X. MODE_LINE_P non-zero means mouse is on the
+ mode line. X is relative to the start of the text display area of
+ W, so the width of fringes and scroll bars must be subtracted
+ to get a position relative to the start of the mode line. */
+static void
+IT_note_mode_line_highlight (struct window *w, int x, int mode_line_p)
+{
+ struct frame *f = XFRAME (w->frame);
+ struct display_info *dpyinfo = FRAME_X_DISPLAY_INFO (f);
+ struct glyph_row *row;
+
+ if (mode_line_p)
+ row = MATRIX_MODE_LINE_ROW (w->current_matrix);
+ else
+ row = MATRIX_HEADER_LINE_ROW (w->current_matrix);
+
+ if (row->enabled_p)
+ {
+ extern Lisp_Object Qhelp_echo;
+ struct glyph *glyph, *end;
+ Lisp_Object help, map;
+
+ /* Find the glyph under X. */
+ glyph = (row->glyphs[TEXT_AREA]
+ + x
+ /* in case someone implements scroll bars some day... */
+ - WINDOW_LEFT_SCROLL_BAR_AREA_WIDTH (w));
+ end = glyph + row->used[TEXT_AREA];
+ if (glyph < end
+ && STRINGP (glyph->object)
+ && STRING_INTERVALS (glyph->object)
+ && glyph->charpos >= 0
+ && glyph->charpos < SCHARS (glyph->object))
+ {
+ /* If we're on a string with `help-echo' text property,
+ arrange for the help to be displayed. This is done by
+ setting the global variable help_echo to the help string. */
+ help = Fget_text_property (make_number (glyph->charpos),
+ Qhelp_echo, glyph->object);
+ if (!NILP (help))
+ {
+ help_echo_string = help;
+ XSETWINDOW (help_echo_window, w);
+ help_echo_object = glyph->object;
+ help_echo_pos = glyph->charpos;
+ }
+ }
+ }
+}
+
+/* Take proper action when the mouse has moved to position X, Y on
+ frame F as regards highlighting characters that have mouse-face
+ properties. Also de-highlighting chars where the mouse was before.
+ X and Y can be negative or out of range. */
+static void
+IT_note_mouse_highlight (struct frame *f, int x, int y)
+{
+ struct display_info *dpyinfo = FRAME_X_DISPLAY_INFO (f);
+ enum window_part part = ON_NOTHING;
+ Lisp_Object window;
+ struct window *w;
+
+ /* When a menu is active, don't highlight because this looks odd. */
+ if (mouse_preempted)
+ return;
+
+ if (NILP (Vmouse_highlight)
+ || !f->glyphs_initialized_p)
+ return;
+
+ dpyinfo->mouse_face_mouse_x = x;
+ dpyinfo->mouse_face_mouse_y = y;
+ dpyinfo->mouse_face_mouse_frame = f;
+
+ if (dpyinfo->mouse_face_defer)
+ return;
+
+ if (gc_in_progress)
+ {
+ dpyinfo->mouse_face_deferred_gc = 1;
+ return;
+ }
+
+ /* Which window is that in? */
+ window = window_from_coordinates (f, x, y, &part, &x, &y, 0);
+
+ /* If we were displaying active text in another window, clear that. */
+ if (! EQ (window, dpyinfo->mouse_face_window))
+ clear_mouse_face (dpyinfo);
+
+ /* Not on a window -> return. */
+ if (!WINDOWP (window))
+ return;
+
+ /* Convert to window-relative coordinates. */
+ w = XWINDOW (window);
+
+ if (part == ON_MODE_LINE || part == ON_HEADER_LINE)
+ {
+ /* Mouse is on the mode or top line. */
+ IT_note_mode_line_highlight (w, x, part == ON_MODE_LINE);
+ return;
+ }
+
+ IT_set_mouse_pointer (0);
+
+ /* Are we in a window whose display is up to date?
+ And verify the buffer's text has not changed. */
+ if (part == ON_TEXT
+ && EQ (w->window_end_valid, w->buffer)
+ && XFASTINT (w->last_modified) == BUF_MODIFF (XBUFFER (w->buffer))
+ && (XFASTINT (w->last_overlay_modified)
+ == BUF_OVERLAY_MODIFF (XBUFFER (w->buffer))))
+ {
+ int pos, i, nrows = w->current_matrix->nrows;
+ struct glyph_row *row;
+ struct glyph *glyph;
+
+ /* Find the glyph under X/Y. */
+ glyph = NULL;
+ if (y >= 0 && y < nrows)
+ {
+ row = MATRIX_ROW (w->current_matrix, y);
+ /* Give up if some row before the one we are looking for is
+ not enabled. */
+ for (i = 0; i <= y; i++)
+ if (!MATRIX_ROW (w->current_matrix, i)->enabled_p)
+ break;
+ if (i > y /* all rows upto and including the one at Y are enabled */
+ && row->displays_text_p
+ && x < window_box_width (w, TEXT_AREA))
+ {
+ glyph = row->glyphs[TEXT_AREA];
+ if (x >= row->used[TEXT_AREA])
+ glyph = NULL;
+ else
+ {
+ glyph += x;
+ if (!BUFFERP (glyph->object))
+ glyph = NULL;
+ }
+ }
+ }
+
+ /* Clear mouse face if X/Y not over text. */
+ if (glyph == NULL)
+ {
+ clear_mouse_face (dpyinfo);
+ return;
+ }
+
+ if (!BUFFERP (glyph->object))
+ abort ();
+ pos = glyph->charpos;
+
+ /* Check for mouse-face and help-echo. */
+ {
+ extern Lisp_Object Qmouse_face;
+ Lisp_Object mouse_face, overlay, position, *overlay_vec;
+ int noverlays, obegv, ozv;;
+ struct buffer *obuf;
+
+ /* If we get an out-of-range value, return now; avoid an error. */
+ if (pos > BUF_Z (XBUFFER (w->buffer)))
+ return;
+
+ /* Make the window's buffer temporarily current for
+ overlays_at and compute_char_face. */
+ obuf = current_buffer;
+ current_buffer = XBUFFER (w->buffer);
+ obegv = BEGV;
+ ozv = ZV;
+ BEGV = BEG;
+ ZV = Z;
+
+ /* Is this char mouse-active or does it have help-echo? */
+ XSETINT (position, pos);
+
+ /* Put all the overlays we want in a vector in overlay_vec. */
+ GET_OVERLAYS_AT (pos, overlay_vec, noverlays, NULL, 0);
+ /* Sort overlays into increasing priority order. */
+ noverlays = sort_overlays (overlay_vec, noverlays, w);
+
+ /* Check mouse-face highlighting. */
+ if (! (EQ (window, dpyinfo->mouse_face_window)
+ && y >= dpyinfo->mouse_face_beg_row
+ && y <= dpyinfo->mouse_face_end_row
+ && (y > dpyinfo->mouse_face_beg_row
+ || x >= dpyinfo->mouse_face_beg_col)
+ && (y < dpyinfo->mouse_face_end_row
+ || x < dpyinfo->mouse_face_end_col
+ || dpyinfo->mouse_face_past_end)))
+ {
+ /* Clear the display of the old active region, if any. */
+ clear_mouse_face (dpyinfo);
+
+ /* Find highest priority overlay that has a mouse-face prop. */
+ overlay = Qnil;
+ for (i = noverlays - 1; i >= 0; --i)
+ {
+ mouse_face = Foverlay_get (overlay_vec[i], Qmouse_face);
+ if (!NILP (mouse_face))
+ {
+ overlay = overlay_vec[i];
+ break;
+ }
+ }
+
+ /* If no overlay applies, get a text property. */
+ if (NILP (overlay))
+ mouse_face = Fget_text_property (position, Qmouse_face,
+ w->buffer);
+
+ /* Handle the overlay case. */
+ if (! NILP (overlay))
+ {
+ /* Find the range of text around this char that
+ should be active. */
+ Lisp_Object before, after;
+ int ignore;
+
+ before = Foverlay_start (overlay);
+ after = Foverlay_end (overlay);
+ /* Record this as the current active region. */
+ fast_find_position (w, XFASTINT (before),
+ &dpyinfo->mouse_face_beg_col,
+ &dpyinfo->mouse_face_beg_row);
+ dpyinfo->mouse_face_past_end
+ = !fast_find_position (w, XFASTINT (after),
+ &dpyinfo->mouse_face_end_col,
+ &dpyinfo->mouse_face_end_row);
+ dpyinfo->mouse_face_window = window;
+ dpyinfo->mouse_face_face_id
+ = face_at_buffer_position (w, pos, 0, 0,
+ &ignore, pos + 1,
+ !dpyinfo->mouse_face_hidden);
+
+ /* Display it as active. */
+ show_mouse_face (dpyinfo, 1);
+ }
+ /* Handle the text property case. */
+ else if (! NILP (mouse_face))
+ {
+ /* Find the range of text around this char that
+ should be active. */
+ Lisp_Object before, after, beginning, end;
+ int ignore;
+
+ beginning = Fmarker_position (w->start);
+ XSETINT (end, (BUF_Z (XBUFFER (w->buffer))
+ - XFASTINT (w->window_end_pos)));
+ before
+ = Fprevious_single_property_change (make_number (pos + 1),
+ Qmouse_face,
+ w->buffer, beginning);
+ after
+ = Fnext_single_property_change (position, Qmouse_face,
+ w->buffer, end);
+ /* Record this as the current active region. */
+ fast_find_position (w, XFASTINT (before),
+ &dpyinfo->mouse_face_beg_col,
+ &dpyinfo->mouse_face_beg_row);
+ dpyinfo->mouse_face_past_end
+ = !fast_find_position (w, XFASTINT (after),
+ &dpyinfo->mouse_face_end_col,
+ &dpyinfo->mouse_face_end_row);
+ dpyinfo->mouse_face_window = window;
+ dpyinfo->mouse_face_face_id
+ = face_at_buffer_position (w, pos, 0, 0,
+ &ignore, pos + 1,
+ !dpyinfo->mouse_face_hidden);
+
+ /* Display it as active. */
+ show_mouse_face (dpyinfo, 1);
+ }
+ }
+
+ /* Look for a `help-echo' property. */
+ {
+ Lisp_Object help;
+ extern Lisp_Object Qhelp_echo;
+
+ /* Check overlays first. */
+ help = Qnil;
+ for (i = noverlays - 1; i >= 0 && NILP (help); --i)
+ {
+ overlay = overlay_vec[i];
+ help = Foverlay_get (overlay, Qhelp_echo);
+ }
+
+ if (!NILP (help))
+ {
+ help_echo_string = help;
+ help_echo_window = window;
+ help_echo_object = overlay;
+ help_echo_pos = pos;
+ }
+ /* Try text properties. */
+ else if (NILP (help)
+ && ((STRINGP (glyph->object)
+ && glyph->charpos >= 0
+ && glyph->charpos < SCHARS (glyph->object))
+ || (BUFFERP (glyph->object)
+ && glyph->charpos >= BEGV
+ && glyph->charpos < ZV)))
+ {
+ help = Fget_text_property (make_number (glyph->charpos),
+ Qhelp_echo, glyph->object);
+ if (!NILP (help))
+ {
+ help_echo_string = help;
+ help_echo_window = window;
+ help_echo_object = glyph->object;
+ help_echo_pos = glyph->charpos;
+ }
+ }
+ }
+
+ BEGV = obegv;
+ ZV = ozv;
+ current_buffer = obuf;
+ }
+ }
+}
+