Brush up the openglunderqml example

- Use suffix-less RHI constants (see
  23dbe3d6e0d3338812ad9f614028a6fdc5a54090).
- Remove unneeded assignments
- Add slot decorator
- Streamline code

Amends b31f0c37bdc78e939db2dfe3bd876eba47137a5c.

Pick-to: 6.2
Fixes: PYSIDE-1716
Task-number: PYSIDE-1034
Change-Id: Ib34be3642d3c2b5f3582889bdc5f0d8d7cebe007
Reviewed-by: Christian Tismer <tismer@stackless.com>

3 files changed, 8 insertions, 11 deletions

diff --git a/examples/declarative/openglunderqml/main.py b/examples/declarative/openglunderqml/main.py
index 26e059f93..44ee10834 100644
--- a/examples/declarative/openglunderqml/main.py
+++ b/examples/declarative/openglunderqml/main.py
@@ -51,7 +51,7 @@ from squircle import Squircle
 if __name__ == "__main__":
     app = QGuiApplication(sys.argv)
 
-    QQuickWindow.setGraphicsApi(QSGRendererInterface.OpenGLRhi)
+    QQuickWindow.setGraphicsApi(QSGRendererInterface.OpenGL)
     qmlRegisterType(Squircle, "OpenGLUnderQML", 1, 0, "Squircle")
 
     view = QQuickView()
diff --git a/examples/declarative/openglunderqml/squircle.py b/examples/declarative/openglunderqml/squircle.py
index 8d2cbca84..3e600121b 100644
--- a/examples/declarative/openglunderqml/squircle.py
+++ b/examples/declarative/openglunderqml/squircle.py
@@ -82,21 +82,23 @@ class Squircle(QQuickItem):
             win.setColor(Qt.black)
             self.sync()
 
+    @Slot()
     def cleanup(self):
         del self._renderer
         self._renderer = None
 
     @Slot()
     def sync(self):
+        window = self.window()
         if not self._renderer:
             self._renderer = SquircleRenderer()
-            self.window().beforeRendering.connect(self._renderer.init, Qt.DirectConnection)
-            self.window().beforeRenderPassRecording.connect(
+            window.beforeRendering.connect(self._renderer.init, Qt.DirectConnection)
+            window.beforeRenderPassRecording.connect(
                 self._renderer.paint, Qt.DirectConnection
             )
-        self._renderer.setViewportSize(self.window().size() * self.window().devicePixelRatio())
+        self._renderer.setViewportSize(window.size() * window.devicePixelRatio())
         self._renderer.setT(self._t)
-        self._renderer.setWindow(self.window())
+        self._renderer.setWindow(window)
 
     def releaseResources(self):
         self.window().scheduleRenderJob(
diff --git a/examples/declarative/openglunderqml/squirclerenderer.py b/examples/declarative/openglunderqml/squirclerenderer.py
index 12cd93bb8..9f857f55f 100644
--- a/examples/declarative/openglunderqml/squirclerenderer.py
+++ b/examples/declarative/openglunderqml/squirclerenderer.py
@@ -80,8 +80,6 @@ class SquircleRenderer(QOpenGLFunctions):
         self._t = 0.0
         self._program = None
         self._window = QQuickWindow()
-        self.profile = QOpenGLVersionProfile()
-        self.gl = None
 
     def setT(self, t):
         self._t = t
@@ -96,10 +94,7 @@ class SquircleRenderer(QOpenGLFunctions):
     def init(self):
         if not self._program:
             rif = self._window.rendererInterface()
-            assert (
-                rif.graphicsApi() == QSGRendererInterface.OpenGL
-                or rif.graphicsApi() == QSGRendererInterface.OpenGLRhy
-            )
+            assert (rif.graphicsApi() == QSGRendererInterface.OpenGL)
             self.initializeOpenGLFunctions()
             self._program = QOpenGLShaderProgram()
             self._program.addCacheableShaderFromSourceCode(QOpenGLShader.Vertex, VERTEX_SHADER)