Automatically choose the best annotation based on visual width

[pulseview.git] / pv / view / decode / annotation.cpp

diff --git a/pv/view/decode/annotation.cpp b/pv/view/decode/annotation.cpp
index 4d9a048357bbe1ea7054edeb0dd64388d5217833..4ad04f23caf34b155d0f938e18bc7d338de73e16 100644 (file)
--- a/pv/view/decode/annotation.cpp
+++ b/pv/view/decode/annotation.cpp
@@ -22,6 +22,12 @@ extern "C" {
 #include <libsigrokdecode/libsigrokdecode.h>
 }
 
+#include <extdef.h>
+
+#include <algorithm>
+
+#include <QPainter>
+
 #include "annotation.h"
 
 using namespace boost;
@@ -31,6 +37,8 @@ namespace pv {
 namespace view {
 namespace decode {
 
+const double Annotation::EndCapWidth = 5;
+
 Annotation::Annotation(const srd_proto_data *const pdata) :
        _start_sample(pdata->start_sample),
        _end_sample(pdata->end_sample)
@@ -42,6 +50,60 @@ Annotation::Annotation(const srd_proto_data *const pdata) :
        }
 }
 
+void Annotation::paint(QPainter &p, QColor fill, QColor outline,
+       QColor text_color, int text_height, int left, int right,
+       double samples_per_pixel, double pixels_offset, int y)
+{
+       const int h = (text_height * 3) / 2;
+
+       const double start = _start_sample / samples_per_pixel -
+               pixels_offset;
+       const double end = _end_sample / samples_per_pixel -
+               pixels_offset;
+
+       if (start > right || end < left)
+               return;
+
+       const double cap_width = min((end - start) / 2, EndCapWidth);
+
+       QPointF pts[] = {
+               QPointF(start, y + .5f),
+               QPointF(start + cap_width, y + .5f - h / 2),
+               QPointF(end - cap_width, y + .5f - h / 2),
+               QPointF(end, y + .5f),
+               QPointF(end - cap_width, y + .5f + h / 2),
+               QPointF(start + cap_width, y + .5f + h / 2)
+       };
+
+       p.setPen(outline);
+       p.setBrush(fill);
+       p.drawConvexPolygon(pts, countof(pts));
+
+       if (_annotations.empty())
+               return;
+
+       QRectF rect(start + cap_width, y - h / 2,
+               end - start - cap_width * 2, h);
+       p.setPen(text_color);
+
+       // Try to find an annotation that will fit
+       QString best_annotation;
+       int best_width = 0;
+
+       BOOST_FOREACH(QString &a, _annotations) {
+               const int w = p.boundingRect(QRectF(), 0, a).width();
+               if (w <= rect.width() && w > best_width)
+                       best_annotation = a, best_width = w;
+       }
+
+       if (best_annotation.isEmpty())
+               best_annotation = _annotations.back();
+
+       // If not ellide the last in the list
+       p.drawText(rect, Qt::AlignCenter, p.fontMetrics().elidedText(
+               best_annotation, Qt::ElideRight, rect.width()));
+}
+
 } // namespace decode
 } // namespace view
 } // namespace pv