Avoid some caret ghosts

When the caret is at end of row, if may happen that it is drawn after
the end of the row. In this case caret blinking will not work
properly. This patch extends the row background on the left and right
by Inset::TEXT_TO_INSET_OFFSET. This is only a hack that will not work
if the caret has a ridiculous width like 6.

Additionally, introduce some (disabled) debug code that numbers the
rows on screen by painting order.

Finally, make the code that detects whether the caret was in a given
row more precise (take boundary into account).

Fixes (mostly, see above) bug #10797.

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index 7828be1d3dce8326562dfcb779740901ee07cce3..831fa8565ce8dce57159696894309784f94d0971 100644 (file)
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -2975,7 +2975,7 @@ namespace {
 bool sliceInRow(CursorSlice const & cs, Text const * text, Row const & row)
 {
        return !cs.empty() && cs.text() == text && cs.pit() == row.pit()
-               && row.pos() <= cs.pos() && cs.pos() <= row.endpos();
+               && row.pos() <= cs.pos() && cs.pos() < row.endpos();
 }
 
 }
@@ -3158,9 +3158,11 @@ void BufferView::draw(frontend::Painter & pain, bool paint_caret)
        }
 
        // Remember what has just been done for the next draw() step
-       if (paint_caret)
+       if (paint_caret) {
                d->caret_slice_ = d->cursor_.top();
-       else
+               if (d->cursor_.boundary())
+                       --d->caret_slice_.pos();
+       } else
                d->caret_slice_ = CursorSlice();
 }
 

diff --git a/src/TextMetrics.cpp b/src/TextMetrics.cpp
index d710e5f80afea656696a108d23c77ff473a294ad..d81fe9e703417b55732360009a656a787d9a393c 100644 (file)
--- a/src/TextMetrics.cpp
+++ b/src/TextMetrics.cpp
@@ -45,6 +45,7 @@
 #include "frontends/Painter.h"
 #include "frontends/NullPainter.h"
 
+#include "support/convert.h"
 #include "support/debug.h"
 #include "support/lassert.h"
 
@@ -1925,8 +1926,16 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type const pit, int const
                        LYXERR(Debug::PAINTING, "Clear rect@("
                               << max(row_x, 0) << ", " << y - row.ascent() << ")="
                               << width() << " x " << row.height());
-                       pi.pain.fillRectangle(max(row_x, 0), y - row.ascent(),
-                               width(), row.height(), pi.background_color);
+                       // FIXME: this is a hack. We know that at least this
+                       // amount of pixels can be cleared on right and left.
+                       // Doing so gets rid of caret ghosts when the cursor is at
+                       // the begining/end of row. However, it will not work if
+                       // the caret has a ridiculous width like 6. (see ticket
+                       // #10797)
+                       pi.pain.fillRectangle(max(row_x, 0) - Inset::TEXT_TO_INSET_OFFSET,
+                                             y - row.ascent(),
+                                             width() + 2 * Inset::TEXT_TO_INSET_OFFSET,
+                                             row.height(), pi.background_color);
                }
 
                // Instrumentation for testing row cache (see also
@@ -1964,6 +1973,20 @@ void TextMetrics::drawParagraph(PainterInfo & pi, pit_type const pit, int const
                                      row_x + row.right_x() > bv_->workWidth());
                y += row.descent();
 
+#if 0
+               // This debug code shows on screen which rows are repainted.
+               // FIXME: since the updates related to caret blinking restrict
+               // the painter to a small rectangle, the numbers are not
+               // updated when this happens. Change the code in
+               // GuiWorkArea::Private::show/hideCaret if this is important.
+               static int count = 0;
+               ++count;
+               FontInfo fi(sane_font);
+               fi.setSize(FONT_SIZE_TINY);
+               fi.setColor(Color_red);
+               pi.pain.text(row_x, y, convert<docstring>(count), fi);
+#endif
+
                // Restore full_repaint status.
                pi.full_repaint = tmp;