DecodeTrace: Speed up annotation drawing

The speedup is achieved by combining neighbouring annotations
into a single item to be drawn if their end pixels are less than
2 pixels apart.

This fixes bug #325.

diff --git a/pv/view/decodetrace.cpp b/pv/view/decodetrace.cpp
index 61f67b9eb584ca424786e59c753b0354fb4e1216..31ea9d73647f42ba7436753a305f267a235337d3 100644 (file)
--- a/pv/view/decodetrace.cpp
+++ b/pv/view/decodetrace.cpp
@@ -211,9 +211,9 @@ void DecodeTrace::paint_mid(QPainter &p, const ViewItemPaintParams &pp)
                decoder_stack_->get_annotation_subset(annotations, row,
                        sample_range.first, sample_range.second);
                if (!annotations.empty()) {
-                       for (const Annotation &a : annotations)
-                               draw_annotation(a, p, annotation_height,
-                                       pp, y, base_colour);
+                       draw_annotations(annotations, p, annotation_height, pp, y,
+                               base_colour);
+
                        y += row_height_;
 
                        visible_rows_.push_back(rows[i]);
@@ -327,6 +327,48 @@ QMenu* DecodeTrace::create_context_menu(QWidget *parent)
        return menu;
 }
 
+void DecodeTrace::draw_annotations(vector<pv::data::decode::Annotation> annotations,
+               QPainter &p, int h, const ViewItemPaintParams &pp, int y,
+               size_t base_colour)
+{
+       using namespace pv::data::decode;
+
+       vector<Annotation> a_block;
+       int prev_ann_pos = INT_MIN;
+
+       double samples_per_pixel, pixels_offset;
+       tie(pixels_offset, samples_per_pixel) =
+               get_pixels_offset_samples_per_pixel();
+
+       // Gather all annotations that form a visual "block" and draw them as such
+       for (const Annotation &a : annotations) {
+
+               const int end = a.end_sample() / samples_per_pixel - pixels_offset;
+               const int delta = end - prev_ann_pos;
+
+               // Some annotations are in reverse order, so we cannot
+               // simply check for delta > 1
+               if (abs(delta) > 1) {
+                       // Block was broken, draw it
+                       if (a_block.size() == 1)
+                               draw_annotation(a_block.front(), p, h, pp, y, base_colour);
+                       else
+                               if (a_block.size() > 0)
+                                       draw_annotation_block(a_block, p, h, pp, y, base_colour);
+
+                       a_block.clear();
+               }
+
+               a_block.push_back(a);
+               prev_ann_pos = end;
+       }
+
+       if (a_block.size() == 1)
+               draw_annotation(a_block.front(), p, h, pp, y, base_colour);
+       else
+               draw_annotation_block(a_block, p, h, pp, y, base_colour);
+}
+
 void DecodeTrace::draw_annotation(const pv::data::decode::Annotation &a,
        QPainter &p, int h, const ViewItemPaintParams &pp, int y,
        size_t base_colour) const
@@ -353,6 +395,33 @@ void DecodeTrace::draw_annotation(const pv::data::decode::Annotation &a,
                draw_range(a, p, fill, outline, h, start, end, y);
 }
 
+void DecodeTrace::draw_annotation_block(vector<pv::data::decode::Annotation> a,
+       QPainter &p, int h, const ViewItemPaintParams &pp, int y,
+       size_t base_colour) const
+{
+       double samples_per_pixel, pixels_offset;
+       tie(pixels_offset, samples_per_pixel) =
+               get_pixels_offset_samples_per_pixel();
+
+       const size_t colour =
+               (base_colour + a.front().format()) % countof(Colours);
+
+       const int start = a.front().start_sample() / samples_per_pixel -
+               pixels_offset;
+       const int end = a.back().end_sample() / samples_per_pixel -
+               pixels_offset;
+
+       const QRectF rect(
+               std::max(pp.left(), start),
+               y - h/2 + 0.5,
+               std::min(pp.right(), end) - std::max(pp.left(), start) + 1,
+               h);
+
+       p.setPen(OutlineColours[colour]);
+       p.setBrush(Colours[colour]);
+       p.drawRect(rect);
+}
+
 void DecodeTrace::draw_instant(const pv::data::decode::Annotation &a, QPainter &p,
        QColor fill, QColor outline, int h, double x, int y) const
 {

diff --git a/pv/view/decodetrace.hpp b/pv/view/decodetrace.hpp
index 5ec7ee7c5337bd1cdf929f70597c26fe9defa78c..954ac90ca420e84c8bd596a95607fbaf960995c9 100644 (file)
--- a/pv/view/decodetrace.hpp
+++ b/pv/view/decodetrace.hpp
@@ -26,6 +26,7 @@
 #include <list>
 #include <map>
 #include <memory>
+#include <vector>
 
 #include <QSignalMapper>
 
@@ -124,10 +125,18 @@ public:
        void delete_pressed();
 
 private:
+       void draw_annotations(std::vector<pv::data::decode::Annotation> annotations,
+               QPainter &p, int h, const ViewItemPaintParams &pp, int y,
+               size_t base_colour);
+
        void draw_annotation(const pv::data::decode::Annotation &a, QPainter &p,
                int text_height, const ViewItemPaintParams &pp, int y,
                size_t base_colour) const;
 
+       void draw_annotation_block(std::vector<pv::data::decode::Annotation> a,
+               QPainter &p, int h, const ViewItemPaintParams &pp, int y,
+               size_t base_colour) const;
+
        void draw_instant(const pv::data::decode::Annotation &a, QPainter &p,
                QColor fill, QColor outline, int h, double x, int y) const;