FallApart effect requires OpenGL

It does quad transformations which is only supported in the OpenGL
compositor.

REVIEW: 111176

effects/fallapart/fallapart.cpp

@@ -28,6 +28,12 @@ namespace KWin
 {
 
 KWIN_EFFECT(fallapart, FallApartEffect)
+KWIN_EFFECT_SUPPORTED(fallapart, FallApartEffect::supported())
+
+bool FallApartEffect::supported()
+{
+    return effects->isOpenGLCompositing();
+}
 
 FallApartEffect::FallApartEffect()
 {

effects/fallapart/fallapart.desktop

@@ -161,3 +161,4 @@ X-KDE-PluginInfo-License=GPL
 X-KDE-PluginInfo-EnabledByDefault=false
 X-KDE-Library=kwin4_effect_builtins
 X-KDE-Ordering=70
+X-KWin-Requires-OpenGL=true

effects/fallapart/fallapart.h

@@ -44,6 +44,9 @@ public:
     int configuredBlockSize() const {
         return blockSize;
     }
+
+    static bool supported();
+
 public Q_SLOTS:
     void slotWindowClosed(KWin::EffectWindow *c);
     void slotWindowDeleted(KWin::EffectWindow *w);