[pitivi] previewers: Try to make sense out of _compute_geometry

[Mathieu Duponchelle <mathieudu src gnome org>]

commit 43d92487b9ee0239432b854b7aa5cf7cc6a09139
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Mon Jan 13 17:25:03 2014 +0100

    previewers: Try to make sense out of _compute_geometry

 pitivi/timeline/previewers.py |   34 +++++++++++++++++-----------------
 1 files changed, 17 insertions(+), 17 deletions(-)
---
diff --git a/pitivi/timeline/previewers.py b/pitivi/timeline/previewers.py
index 464782b..bb7d2ed 100644
--- a/pitivi/timeline/previewers.py
+++ b/pitivi/timeline/previewers.py
@@ -806,34 +806,34 @@ class AudioPreviewer(Clutter.Actor, PreviewGenerator, Zoomable, Loggable):
 
     def _compute_geometry(self):
         self.log("Computing the clip's geometry for waveforms")
-        start = self.timeline.get_scroll_point().x - self.nsToPixel(self.bElement.props.start)
-        start = max(0, start)
-        end = min(self.timeline.get_scroll_point().x + self.timeline._container.get_allocation().width - 
CONTROL_WIDTH + MARGIN,
-                  self.nsToPixel(self.bElement.props.duration))
-
         width_px = self.nsToPixel(self.bElement.props.duration)
         if width_px <= 0:
             return
-
-        asset_duration = self.bElement.get_parent().get_asset().get_duration()
+        start = self.timeline.get_scroll_point().x - self.nsToPixel(self.bElement.props.start)
+        start = max(0, start)
+        # Take into account the timeline width, to avoid building
+        # huge clips when the timeline is zoomed in a lot.
+        timeline_width = self.timeline._container.get_allocation().width - CONTROL_WIDTH
+        end = min(width_px,
+                  self.timeline.get_scroll_point().x + timeline_width + MARGIN)
+        self.width = int(end - start)
+        if self.width < 0:  # We've been called at a moment where size was updated but not scroll_point.
+            return
 
         # We need to take duration and inpoint into account.
-
-        nbSamples = self.nbSamples
-        startOffsetSamples = 0
-
-        if self.bElement.props.duration != 0:
+        asset_duration = self.bElement.get_parent().get_asset().get_duration()
+        if self.bElement.props.duration:
             nbSamples = self.nbSamples / (float(asset_duration) / float(self.bElement.props.duration))
-        if self.bElement.props.in_point != 0:
+        else:
+            nbSamples = self.nbSamples
+        if self.bElement.props.in_point:
             startOffsetSamples = self.nbSamples / (float(asset_duration) / 
float(self.bElement.props.in_point))
+        else:
+            startOffsetSamples = 0
 
         self.start = int(start / width_px * nbSamples + startOffsetSamples)
         self.end = int(end / width_px * nbSamples + startOffsetSamples)
 
-        self.width = int(end - start)
-        if self.width < 0:  # We've been called at a moment where size was updated but not scroll_point.
-            return
-
         self.canvas.set_size(self.width, EXPANDED_SIZE)
         Clutter.Actor.set_size(self, self.width, EXPANDED_SIZE)
         self.set_position(start, self.props.y)