three-stage drawing: add a nodraw stage

[features.git] / src / BufferView.cpp

diff --git a/src/BufferView.cpp b/src/BufferView.cpp
index d2215627cfbdb2ef7be4b54793ce4dc5ed78dd99..00de06080ad75e4a4e76d83b5b1fa95558627b54 100644 (file)
--- a/src/BufferView.cpp
+++ b/src/BufferView.cpp
@@ -70,6 +70,7 @@
 #include "frontends/Application.h"
 #include "frontends/Delegates.h"
 #include "frontends/FontMetrics.h"
+#include "frontends/NullPainter.h"
 #include "frontends/Painter.h"
 #include "frontends/Selection.h"
 
@@ -2745,6 +2746,9 @@ void BufferView::updateMetrics()
 
        d->update_strategy_ = FullScreenUpdate;
 
+       // Now update the positions of insets in the cache.
+       updatePosCache();
+
        if (lyxerr.debugging(Debug::WORKAREA)) {
                LYXERR(Debug::WORKAREA, "BufferView::updateMetrics");
                d->coord_cache_.dump();
@@ -2752,6 +2756,15 @@ void BufferView::updateMetrics()
 }
 
 
+void BufferView::updatePosCache()
+{
+       // this is the "nodraw" drawing stage: only set the positions of the
+       // insets in metrics cache.
+       frontend::NullPainter np;
+       draw(np);
+}
+
+
 void BufferView::insertLyXFile(FileName const & fname)
 {
        LASSERT(d->cursor_.inTexted(), return);
@@ -2997,12 +3010,11 @@ void BufferView::checkCursorScrollOffset(PainterInfo & pi)
                 * at this point.
                 */
                // Force the recomputation of inset positions
-               bool const drawing = pi.pain.isDrawingEnabled();
-               pi.pain.setDrawingEnabled(false);
+               frontend::NullPainter np;
+               PainterInfo(this, np);
                // No need to care about vertical position.
                RowPainter rp(pi, buffer().text(), row, -d->horiz_scroll_offset_, 0);
                rp.paintText();
-               pi.pain.setDrawingEnabled(drawing);
        }
 
        // Current x position of the cursor in pixels
@@ -3066,12 +3078,13 @@ void BufferView::draw(frontend::Painter & pain)
        switch (d->update_strategy_) {
 
        case NoScreenUpdate:
-               // If no screen painting is actually needed, only some the different
-               // coordinates of insets and paragraphs needs to be updated.
+               // no screen painting is actually needed. In nodraw stage
+               // however, the different coordinates of insets and paragraphs
+               // needs to be updated.
                LYXERR(Debug::PAINTING, "Strategy: NoScreenUpdate");
                pi.full_repaint = true;
-               pi.pain.setDrawingEnabled(false);
-               tm.draw(pi, 0, y);
+               if (pain.isNull())
+                       tm.draw(pi, 0, y);
                break;
 
        case SingleParUpdate: