From: Michal Malý <madcatxster@devoid-pointer.net>
Date: Fri, 10 Oct 2014 00:59:37 +0000 (+0200)
Subject: Do not draw graph below time axis (has a few glitches)
X-Git-Tag: 0.3e~4
X-Git-Url: https://gitweb.devoid-pointer.net/?a=commitdiff_plain;h=8f940b4c05c7d4ddb61f7371bca9d77453707f80;p=anyanka.git

Do not draw graph below time axis (has a few glitches)
---

diff --git a/signaldrawer.cpp b/signaldrawer.cpp
index afb4dd5..9b2124b 100644
--- a/signaldrawer.cpp
+++ b/signaldrawer.cpp
@@ -504,7 +504,32 @@ bool SignalDrawer::renderGraph(QPixmap* const target)
   for (size_t i = 1; i < m_gdData->ddataLen; i++) {
     int toXPix = relToXPix(m_gdData->ddata[i].first);
     int toYPix = relToYPix(m_gdData->ddata[i].second);
-    p.drawLine(fromXPix, fromYPix, toXPix, toYPix);
+
+    if (fromYPix > m_gHeight && toYPix > m_gHeight) {
+      /* Draw nothing */
+    } else if (toXPix == fromXPix)
+      p.drawLine(fromXPix, (fromYPix >= m_gHeight) ? m_gHeight : fromYPix, toXPix, (toYPix >= m_gHeight) ? m_gHeight : toYPix);
+    else if (toYPix >= m_gHeight) {
+      double k = static_cast<double>(toYPix - fromYPix) / static_cast<double>(toXPix - fromXPix);
+      double cToYPix = m_gHeight;
+      double cToXPix = (cToYPix - fromYPix + k * fromXPix) / k;
+      if (isnan(cToXPix))
+        cToXPix = fromXPix;
+      else
+        cToXPix = floor(cToXPix + 0.5);
+      p.drawLine(fromXPix, fromYPix, cToXPix, m_gHeight);
+    } else if (fromYPix >= m_gHeight) {
+      double k = static_cast<double>(toYPix - fromYPix) / static_cast<double>(toXPix - fromXPix);
+      double cFromYPix = m_gHeight;
+      double cFromXPix = (cFromYPix - fromYPix + k * fromXPix) / k;
+      if (isnan(cFromXPix))
+        cFromXPix = fromXPix;
+      else
+        cFromXPix = floor(cFromXPix + 0.5);
+      p.drawLine(cFromXPix, m_gHeight, toXPix, toYPix);
+    } else
+      p.drawLine(fromXPix, fromYPix, toXPix, toYPix);
+
     fromXPix = toXPix;
     fromYPix = toYPix;
   }