Merge lp:~townsend/compiz/fix-snap-window-resize-0.9.10 into lp:compiz/0.9.10

[Christopher Townsend]

Remove seemingly useless code in the SnapWindow::resizeNotify() method where a snapped window that is being resized on the opposite side of the snap would cause orders of magnitude more calls to window->resize() and kill performance.

= Issue =
Set Default Resizing mode to Normal. Snap a window to an edge such as the Launcher or the Panel or screen edge. Resize the opposite side of the snapped edge. Terrible performance ensues.

= Fix =
A seemingly useless code block in the SnapWindow::resizeNotify() method would make orders of magnitude more calls to window->resize() in this case. Each call destroys/creates a new X Window. For example a normal resize may call resize 5 times, but with this code in place, it may call 5000 times or more.

= Note =
I could not figure out what the real intent of the code block was for when resizing a window. It just didn't seem like it was supposed to do anything. As a matter of fact, when using the Default Resizing mode as Rectangle, this code was never touched, so it's not as if resizing a snapped window needed to do something special. At any rate, some pretty good testing of various resizing should be done to ensure there is no regressions by removing this code.

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:3795
http://jenkins.qa.ubuntu.com/job/compiz-team-compiz-0.9.10-ci/15/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-team-compiz-0.9.10-saucy-amd64-ci/15
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-team-compiz-0.9.10-saucy-armhf-ci/13
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-team-compiz-0.9.10-saucy-i386-ci/15

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review: Approve (continuous-integration)

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:3795
http://jenkins.qa.ubuntu.com/job/compiz-0.9.10-ci/5/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-0.9.10-saucy-amd64-ci/5
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-0.9.10-saucy-armhf-ci/5
    SUCCESS: http://jenkins.qa.ubuntu.com/job/compiz-0.9.10-saucy-i386-ci/5

Click here to trigger a rebuild:
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review: Approve (continuous-integration)

[Brandon Schaefer (brandontschaefer)]

LGTM

But would like someone else to test it out :)

review: Approve

[Marco Trevisan (Treviño) (3v1n0)]

This seems to work well here, I was jut worried by the possibility that this could lead to non working snapping when resizing a window (if enabled), but I don't see that working even in normal version... So I think this is fine

=== modified file 'plugins/snap/src/snap.cpp'
--- plugins/snap/src/snap.cpp	2013-05-09 13:43:07 +0000
+++ plugins/snap/src/snap.cpp	2013-10-03 18:19:48 +0000
@@ -587,77 +587,6 @@
     if (!ss->snapping)
 	return;
 
-    // apply edge resistance
-    if (ss->optionGetSnapTypeMask () & SnapTypeEdgeResistanceMask)
-    {
-	// If there's horizontal snapping, add dx to current buffered
-	// dx and resist (move by -dx) or release the window and move
-	// by buffered dx - dx, same for dh
-	if (!snapGeometry.isEmpty () && snapDirection & HorizontalSnap)
-	{
-	    m_dx += dx;
-	    if (m_dx < ss->optionGetResistanceDistance ()
-		&& m_dx > -ss->optionGetResistanceDistance ())
-	    {
-		resize (-dx, 0, 0, 0);
-	    }
-	    else
-	    {
-		resize (m_dx - dx, 0, 0, 0);
-		m_dx = 0;
-		if (!m_dwidth)
-		    snapDirection &= VerticalSnap;
-	    }
-	    m_dwidth += dwidth;
-	    if (m_dwidth < ss->optionGetResistanceDistance ()
-		&& m_dwidth > -ss->optionGetResistanceDistance ())
-	    {
-		resize (0, 0, -dwidth, 0);
-	    }
-	    else
-	    {
-		resize (0, 0, m_dwidth - dwidth, 0);
-		m_dwidth = 0;
-		if (!m_dx)
-		    snapDirection &= VerticalSnap;
-	    }
-	}
-
-	// Same for vertical snapping and dy/dh
-	if (snapGeometry.isEmpty () && snapDirection & VerticalSnap)
-	{
-	    m_dy += dy;
-	    if (m_dy < ss->optionGetResistanceDistance ()
-		&& m_dy > -ss->optionGetResistanceDistance ())
-	    {
-		resize (0, -dy, 0, 0);
-	    }
-	    else
-	    {
-		resize (0, m_dy - dy, 0, 0);
-		m_dy = 0;
-		if (!m_dheight)
-		    snapDirection &= HorizontalSnap;
-	    }
-	    m_dheight += dheight;
-	    if (m_dheight < ss->optionGetResistanceDistance ()
-		&& m_dheight > -ss->optionGetResistanceDistance ())
-	    {
-		resize (0, 0, 0, -dheight);
-	    }
-	    else
-	    {
-		resize (0, 0, 0, m_dheight - dheight);
-		m_dheight = 0;
-		if (!m_dy)
-		    snapDirection &= HorizontalSnap;
-	    }
-	}
-	// If we are no longer snapping in any direction, reset snapped
-	if (!snapGeometry.isEmpty () && !snapDirection)
-	    snapGeometry = CompWindow::Geometry ();
-    }
-
     // If we don't already snap vertically and horizontally,
     // check edges status
     if (snapDirection != (VerticalSnap | HorizontalSnap))