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diff --git a/examples/declarative/openglunderqml/squirclerenderer.py b/examples/declarative/openglunderqml/squirclerenderer.py
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+#############################################################################
+##
+## Copyright (C) 2021 The Qt Company Ltd.
+## Contact: http://www.qt.io/licensing/
+##
+## This file is part of the Qt for Python examples of the Qt Toolkit.
+##
+## $QT_BEGIN_LICENSE:BSD$
+## You may use this file under the terms of the BSD license as follows:
+##
+## "Redistribution and use in source and binary forms, with or without
+## modification, are permitted provided that the following conditions are
+## met:
+## * Redistributions of source code must retain the above copyright
+## notice, this list of conditions and the following disclaimer.
+## * Redistributions in binary form must reproduce the above copyright
+## notice, this list of conditions and the following disclaimer in
+## the documentation and/or other materials provided with the
+## distribution.
+## * Neither the name of The Qt Company Ltd nor the names of its
+## contributors may be used to endorse or promote products derived
+## from this software without specific prior written permission.
+##
+##
+## THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+## "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+## LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+## A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+## OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+## SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+## LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+## DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+## THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+## (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+## OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+##
+## $QT_END_LICENSE$
+##
+#############################################################################
+
+from textwrap import dedent
+
+import numpy as np
+from OpenGL.GL import (GL_ARRAY_BUFFER, GL_BLEND, GL_DEPTH_TEST, GL_FLOAT,
+ GL_ONE, GL_SRC_ALPHA, GL_TRIANGLE_STRIP)
+from PySide6.QtCore import QSize, Slot
+from PySide6.QtGui import QOpenGLFunctions
+from PySide6.QtOpenGL import (QOpenGLShader, QOpenGLShaderProgram,
+ QOpenGLVersionProfile)
+from PySide6.QtQuick import QQuickWindow, QSGRendererInterface
+
+VERTEX_SHADER = dedent(
+ """\
+ attribute highp vec4 vertices;
+ varying highp vec2 coords;
+ void main() {
+ gl_Position = vertices;
+ coords = vertices.xy;
+ }
+ """
+)
+FRAGMENT_SHADER = dedent(
+ """\
+ uniform lowp float t;
+ varying highp vec2 coords;
+ void main() {
+ lowp float i = 1. - (pow(abs(coords.x), 4.) + pow(abs(coords.y), 4.));
+ i = smoothstep(t - 0.8, t + 0.8, i);
+ i = floor(i * 20.) / 20.;
+ gl_FragColor = vec4(coords * .5 + .5, i, i);
+ }
+ """
+)
+
+
+class SquircleRenderer(QOpenGLFunctions):
+ def __init__(self):
+ QOpenGLFunctions.__init__(self)
+ self._viewport_size = QSize()
+ self._t = 0.0
+ self._program = None
+ self._window = QQuickWindow()
+ self.profile = QOpenGLVersionProfile()
+ self.gl = None
+
+ def setT(self, t):
+ self._t = t
+
+ def setViewportSize(self, size):
+ self._viewport_size = size
+
+ def setWindow(self, window):
+ self._window = window
+
+ @Slot()
+ def init(self):
+ if not self._program:
+ rif = self._window.rendererInterface()
+ assert (
+ rif.graphicsApi() == QSGRendererInterface.OpenGL
+ or rif.graphicsApi() == QSGRendererInterface.OpenGLRhy
+ )
+ self.initializeOpenGLFunctions()
+ self._program = QOpenGLShaderProgram()
+ self._program.addCacheableShaderFromSourceCode(QOpenGLShader.Vertex, VERTEX_SHADER)
+ self._program.addCacheableShaderFromSourceCode(QOpenGLShader.Fragment, FRAGMENT_SHADER)
+ self._program.bindAttributeLocation("vertices", 0)
+ self._program.link()
+
+ @Slot()
+ def paint(self):
+ # Play nice with the RHI. Not strictly needed when the scenegraph uses
+ # OpenGL directly.
+ self._window.beginExternalCommands()
+
+ self._program.bind()
+
+ self._program.enableAttributeArray(0)
+
+ values = np.array([-1, -1, 1, -1, -1, 1, 1, 1], dtype="single")
+
+ # This example relies on (deprecated) client-side pointers for the vertex
+ # input. Therefore, we have to make sure no vertex buffer is bound.
+ self.glBindBuffer(GL_ARRAY_BUFFER, 0)
+
+ self._program.setAttributeArray(0, GL_FLOAT, values, 2)
+ self._program.setUniformValue1f("t", self._t)
+
+ self.glViewport(0, 0, self._viewport_size.width(), self._viewport_size.height())
+
+ self.glDisable(GL_DEPTH_TEST)
+
+ self.glEnable(GL_BLEND)
+ self.glBlendFunc(GL_SRC_ALPHA, GL_ONE)
+
+ self.glDrawArrays(GL_TRIANGLE_STRIP, 0, 4)
+
+ self._program.disableAttributeArray(0)
+ self._program.release()
+
+ self._window.endExternalCommands()