Merge lp:~hikiko/unity/unity.multimonitor-speed-up into lp:unity

[Eleni Maria Stea]

UnityScreen: only redraw parts of the screen visible in each output

We draw only the parts of the screen that are visible in each output (monitor) because compiz draws things per output anyway. Speeds up the drawing by about N times, where N is the number of monitors because:

We used to draw all monitors' content when 1 monitor was rendered (=> we rendered N times the N monitors' content). Now, we draw only the current monitor's content (we render 1 time each of the N monitors' content).

Fix for multi-monitor:
We draw only the parts of the screen that are visible in each output (monitor) because compiz draws things per output anyway. Speeds up the drawing by about N times, where N is the number of monitors because:

We used to draw all monitors' content when 1 monitor was rendered (=> we rendered N times the N monitors' content). Now, we draw only the current monitor's content (we render 1 time each of the N monitors' content).

[Andrea Azzarone (azzar1)]

Works fine here.

review: Approve

=== modified file 'plugins/unityshell/src/unityshell.cpp'
--- plugins/unityshell/src/unityshell.cpp	2016-06-21 01:28:26 +0000
+++ plugins/unityshell/src/unityshell.cpp	2016-07-02 17:13:04 +0000
@@ -863,7 +863,7 @@
   cScreen->damageRegion(CompRegionFromNuxGeo(blur_update));
 }
 
-void UnityScreen::paintDisplay()
+void UnityScreen::paintOutput()
 {
   CompOutput *output = last_output_;
 
@@ -884,7 +884,7 @@
   current_draw_binding = old_read_binding;
 #endif
 
-  BackgroundEffectHelper::monitor_rect_.Set(0, 0, screen->width(), screen->height());
+  BackgroundEffectHelper::monitor_rect_.Set(0, 0, output->width(), output->height());
 
   // If we have dirty helpers re-copy the backbuffer into a texture
   if (dirty_helpers_on_this_frame_)
@@ -909,10 +909,10 @@
 
     for (CompRect const& rect : blur_region.rects())
     {
-      int x = nux::Clamp<int>(rect.x(), 0, screen->width());
-      int y = nux::Clamp<int>(screen->height() - rect.y2(), 0, screen->height());
-      int width = std::min<int>(screen->width() - rect.x(), rect.width());
-      int height = std::min<int>(screen->height() - y, rect.height());
+      int x = nux::Clamp<int>(rect.x(), 0, output->width());
+      int y = nux::Clamp<int>(output->height() - rect.y2(), 0, output->height());
+      int width = std::min<int>(output->width() - rect.x(), rect.width());
+      int height = std::min<int>(output->height() - y, rect.height());
 
       CHECKGL(glCopyTexSubImage2D(surface_target, 0, x, y, x, y, width, height));
     }
@@ -1504,7 +1504,7 @@
     doShellRepaint = false;
 
   if (doShellRepaint)
-    paintDisplay();
+    paintOutput();
 
   return ret;
 }
@@ -3094,18 +3094,18 @@
 
   if (uScreen->doShellRepaint && window == uScreen->onboard_)
   {
-    uScreen->paintDisplay();
+    uScreen->paintOutput();
   }
   else if (uScreen->doShellRepaint &&
            window == uScreen->firstWindowAboveShell &&
            !uScreen->forcePaintOnTop() &&
            !uScreen->fullscreenRegion.contains(window->geometry()))
   {
-    uScreen->paintDisplay();
+    uScreen->paintOutput();
   }
   else if (locked && CanBypassLockScreen())
   {
-    uScreen->paintDisplay();
+    uScreen->paintOutput();
   }
 
   enum class DrawPanelShadow
 
=== modified file 'plugins/unityshell/src/unityshell.h'
--- plugins/unityshell/src/unityshell.h	2016-06-06 14:05:18 +0000
+++ plugins/unityshell/src/unityshell.h	2016-07-02 17:13:04 +0000
@@ -179,7 +179,7 @@
   void nuxEpilogue();
 
   /* nux draw wrapper */
-  void paintDisplay();
+  void paintOutput();
   void paintPanelShadow(CompRegion const& clip);
   void setPanelShadowMatrix(const GLMatrix& matrix);
   void updateBlurDamage();