Adapt caret height to context in mathed.

Compute a height from current font and current cell vertical
dimensions in MathData::metrics(), because this is where current font
is known.

Introduce BufferView::setCaretAscentDescent to remember this value.

This mechanism is not used for text because Cursor::current_font is
restored by undo, and the caret height would not be changed then. But
in principle it is doable.

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index 8e49f3f6fbae4bdce68c5e79b69485aacff02af0..ed559b152493c06b08b944bd68c11201ebce3d4f 100644 (file)
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -230,7 +230,8 @@ enum ScreenUpdateStrategy {
 
 struct BufferView::Private
 {
-       Private(BufferView & bv) : update_strategy_(FullScreenUpdate),
+       Private(BufferView & bv) :
+               update_strategy_(FullScreenUpdate),
                update_flags_(Update::Force),
                wh_(0), cursor_(bv),
                anchor_pit_(0), anchor_ypos_(0),
@@ -238,7 +239,8 @@ struct BufferView::Private
                last_inset_(0), clickable_inset_(false),
                mouse_position_cache_(),
                bookmark_edit_position_(-1), gui_(0),
-               horiz_scroll_offset_(0)
+               horiz_scroll_offset_(0),
+               caret_ascent_(0), caret_descent_(0)
        {
                xsel_cache_.set = false;
        }
@@ -317,6 +319,12 @@ struct BufferView::Private
        /// a slice pointing to the start of the row where cursor was
        /// at previous draw event
        CursorSlice last_row_slice_;
+
+       // The vertical size of the blinking caret. Only used for math
+       // Using it for text could be bad when undo restores the cursor
+       // current font, since the caret size could become wrong.
+       int caret_ascent_;
+       int caret_descent_;
 };
 
 
@@ -2982,13 +2990,26 @@ bool BufferView::paragraphVisible(DocIterator const & dit) const
 }
 
 
+void BufferView::setCaretAscentDescent(int asc, int des)
+{
+       d->caret_ascent_ = asc;
+       d->caret_descent_ = des;
+}
+
+
 void BufferView::caretPosAndHeight(Point & p, int & h) const
 {
+       int asc, des;
        Cursor const & cur = cursor();
-       Font const font = cur.real_current_font;
-       frontend::FontMetrics const & fm = theFontMetrics(font);
-       int const asc = fm.maxAscent();
-       int const des = fm.maxDescent();
+       if (cur.inMathed()) {
+               asc = d->caret_ascent_;
+               des = d->caret_descent_;
+       } else {
+               Font const font = cur.real_current_font;
+               frontend::FontMetrics const & fm = theFontMetrics(font);
+               asc = fm.maxAscent();
+               des = fm.maxDescent();
+       }
        h = asc + des;
        p = getPos(cur);
        p.y_ -= asc;

diff --git a/src/BufferView.h b/src/BufferView.h
index 0381b6b86fe096ecfc67ae83e2fbc205af881e89..2478e609349857d2ae1ce47c28f8c8891caff053 100644 (file)
--- a/src/BufferView.h
+++ b/src/BufferView.h
@@ -307,6 +307,8 @@ public:
        bool paragraphVisible(DocIterator const & dit) const;
        /// is the cursor currently visible in the view
        bool cursorInView(Point const & p, int h) const;
+       /// set the ascent and descent of the caret
+       void setCaretAscentDescent(int asc, int des);
        /// get the position and height of the caret
        void caretPosAndHeight(Point & p, int & h) const;
 

diff --git a/src/mathed/MathData.cpp b/src/mathed/MathData.cpp
index 719065d0cef2198e30f74870a6e10b54226e69c6..482d50636c0143f862f1ddfe6c6975bd7174d291 100644 (file)
--- a/src/mathed/MathData.cpp
+++ b/src/mathed/MathData.cpp
@@ -262,6 +262,7 @@ bool isInside(DocIterator const & it, MathData const & ar,
 void MathData::metrics(MetricsInfo & mi, Dimension & dim, bool tight) const
 {
        frontend::FontMetrics const & fm = theFontMetrics(mi.base.font);
+       BufferView * bv = mi.base.bv;
        int const Iascent = fm.dimension('I').ascent();
        int xascent = fm.dimension('x').ascent();
        if (xascent >= Iascent)
@@ -273,8 +274,8 @@ void MathData::metrics(MetricsInfo & mi, Dimension & dim, bool tight) const
 
        MathRow mrow(mi, this);
        mrow.metrics(mi, dim);
-       mrow_cache_[mi.base.bv] = mrow;
-       kerning_ = mrow.kerning(mi.base.bv);
+       mrow_cache_[bv] = mrow;
+       kerning_ = mrow.kerning(bv);
 
        // Set a minimal ascent/descent for the cell
        if (tight)
@@ -286,8 +287,15 @@ void MathData::metrics(MetricsInfo & mi, Dimension & dim, bool tight) const
                dim.des = max(dim.des, fm.maxDescent());
        }
 
+       // This is one of the the few points where the drawing font is known,
+       // so that we can set the caret vertical dimensions.
+       Cursor & cur = bv->cursor();
+       if (cur.inMathed() && &cur.cell() == this)
+               bv->setCaretAscentDescent(min(dim.asc, fm.maxAscent()),
+                                         min(dim.des, fm.maxDescent()));
+
        // Cache the dimension.
-       mi.base.bv->coordCache().arrays().add(this, dim);
+       bv->coordCache().arrays().add(this, dim);
 }