Started properties refactoring

src/properties/pieceavailabilitybar.h

@@ -0,0 +1,128 @@
+/*
+ * Bittorrent Client using Qt4 and libtorrent.
+ * Copyright (C) 2006  Christophe Dumez
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ * In addition, as a special exception, the copyright holders give permission to
+ * link this program with the OpenSSL project's "OpenSSL" library (or with
+ * modified versions of it that use the same license as the "OpenSSL" library),
+ * and distribute the linked executables. You must obey the GNU General Public
+ * License in all respects for all of the code used other than "OpenSSL".  If you
+ * modify file(s), you may extend this exception to your version of the file(s),
+ * but you are not obligated to do so. If you do not wish to do so, delete this
+ * exception statement from your version.
+ *
+ * Contact : chris@qbittorrent.org
+ */
+
+#ifndef PIECEAVAILABILITYBAR_H
+#define PIECEAVAILABILITYBAR_H
+
+#include <QWidget>
+#include <QPainter>
+#include <QPixmap>
+#include <QColor>
+#include <numeric>
+#include <math.h>
+
+#define BAR_HEIGHT 18
+
+class PieceAvailabilityBar: public QWidget {
+  Q_OBJECT
+
+private:
+  QPixmap pixmap;
+
+public:
+  PieceAvailabilityBar(QWidget *parent): QWidget(parent) {
+    setFixedHeight(BAR_HEIGHT);
+  }
+
+  void setAvailability(const std::vector<int>& avail) {
+    double average = 0;
+    if(avail.empty()) {
+      // Empty bar
+      QPixmap pix = QPixmap(1, 1);
+      pix.fill();
+      pixmap = pix;
+    } else {
+      // Look for maximum value
+      const qulonglong nb_pieces = avail.size();
+      average = std::accumulate(avail.begin(), avail.end(), 0)/(double)nb_pieces;
+      // Reduce the number of pieces before creating the pixmap
+      // otherwise it can crash when there are too many pieces
+      const uint w = width();
+      if(nb_pieces > w) {
+        const qulonglong ratio = floor(nb_pieces/(double)w);
+        std::vector<int> scaled_avail;
+        scaled_avail.reserve(ceil(nb_pieces/(double)ratio));
+        for(qulonglong i=0; i<nb_pieces; i+= ratio) {
+          /*qulonglong j = i;
+          qulonglong sum = avail[i];
+          for(j=i+1; j<qMin(i+ratio, nb_pieces); ++j) {
+            sum += avail[j];
+          }
+          scaled_avail.push_back(sum/(qMin(ratio, nb_pieces-i)));*/
+          // XXX: Do not compute the average to save cpu
+          scaled_avail.push_back(avail[i]);
+        }
+        QPixmap pix = QPixmap(scaled_avail.size(), 1);
+        //pix.fill();
+        QPainter painter(&pix);
+        for(qulonglong i=0; i < scaled_avail.size(); ++i) {
+          painter.setPen(getPieceColor(scaled_avail[i], average));
+          painter.drawPoint(i,0);
+        }
+        pixmap = pix;
+      } else {
+        QPixmap pix = QPixmap(nb_pieces, 1);
+        //pix.fill();
+        QPainter painter(&pix);
+        for(qulonglong i=0; i < nb_pieces; ++i) {
+          painter.setPen(getPieceColor(avail[i], average));
+          painter.drawPoint(i,0);
+        }
+        pixmap = pix;
+      }
+    }
+    update();
+  }
+
+  void clear() {
+    pixmap = QPixmap();
+    update();
+  }
+
+protected:
+  void paintEvent(QPaintEvent *) {
+    if(pixmap.isNull()) return;
+    QPainter painter(this);
+    painter.drawPixmap(rect(), pixmap);
+  }
+
+  QColor getPieceColor(int avail, double average) {
+    if(!avail) return Qt::white;
+    //qDebug("avail: %d/%d", avail, max_avail);
+    double fraction = 100.*average/avail;
+    if(fraction < 100)
+      fraction *= 0.8;
+    else
+      fraction *= 1.2;
+    return QColor(Qt::blue).lighter(fraction);
+  }
+};
+
+#endif // PIECEAVAILABILITYBAR_H