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authorVolker Hilsheimer <volker.hilsheimer@qt.io>2020-10-28 18:25:27 +0100
committerVolker Hilsheimer <volker.hilsheimer@qt.io>2020-10-29 09:48:28 +0100
commit7635d77689193e729db248300634571aea4d8c81 (patch)
tree3b3d47208c25d209f6d6a9d94b36f8dfab457559 /src/opengl/doc/snippets/code
parent61574ee963a5c3f70ede89c1a7367db621164b6f (diff)
Organize QtOpenGLWidgets documentation
Move snippets to the right place, and give the widgets class a place to live. QtOpenGLWidgets is just a library, not a separate module, but we need a module page that the class can refer to for correct build instructions. Change-Id: I6d955ad3c4cd1003a828cc1f256deb6e7fb50ec4 Reviewed-by: Paul Wicking <paul.wicking@qt.io>
Diffstat (limited to 'src/opengl/doc/snippets/code')
-rw-r--r--src/opengl/doc/snippets/code/doc_gui_widgets_qopenglwidget.cpp209
-rw-r--r--src/opengl/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp68
-rw-r--r--src/opengl/doc/snippets/code/src_gui_opengl_qopengldebug.cpp133
-rw-r--r--src/opengl/doc/snippets/code/src_gui_qopenglshaderprogram.cpp116
4 files changed, 526 insertions, 0 deletions
diff --git a/src/opengl/doc/snippets/code/doc_gui_widgets_qopenglwidget.cpp b/src/opengl/doc/snippets/code/doc_gui_widgets_qopenglwidget.cpp
new file mode 100644
index 0000000000..633a413b4f
--- /dev/null
+++ b/src/opengl/doc/snippets/code/doc_gui_widgets_qopenglwidget.cpp
@@ -0,0 +1,209 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+//! [0]
+class MyGLWidget : public QOpenGLWidget
+{
+public:
+ MyGLWidget(QWidget *parent) : QOpenGLWidget(parent) { }
+
+protected:
+ void initializeGL() override
+ {
+ // Set up the rendering context, load shaders and other resources, etc.:
+ QOpenGLFunctions *f = QOpenGLContext::currentContext()->functions();
+ f->glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
+ ...
+ }
+
+ void resizeGL(int w, int h) override
+ {
+ // Update projection matrix and other size related settings:
+ m_projection.setToIdentity();
+ m_projection.perspective(45.0f, w / float(h), 0.01f, 100.0f);
+ ...
+ }
+
+ void paintGL() override
+ {
+ // Draw the scene:
+ QOpenGLFunctions *f = QOpenGLContext::currentContext()->functions();
+ f->glClear(GL_COLOR_BUFFER_BIT);
+ ...
+ }
+
+};
+//! [0]
+
+//! [1]
+class MyGLWidget : public QOpenGLWidget, protected QOpenGLFunctions
+{
+ ...
+ void initializeGL() override
+ {
+ initializeOpenGLFunctions();
+ glClearColor(...);
+ ...
+ }
+ ...
+};
+//! [1]
+
+//! [2]
+QOpenGLWidget *widget = new QOpenGLWidget(parent);
+QSurfaceFormat format;
+format.setDepthBufferSize(24);
+format.setStencilBufferSize(8);
+format.setVersion(3, 2);
+format.setProfile(QSurfaceFormat::CoreProfile);
+widget->setFormat(format); // must be called before the widget or its parent window gets shown
+//! [2]
+
+//! [3]
+ ...
+ void paintGL() override
+ {
+ QOpenGLFunctions_3_2_Core *f = QOpenGLContext::currentContext()->versionFunctions<QOpenGLFunctions_3_2_Core>();
+ ...
+ f->glDrawArraysInstanced(...);
+ ...
+ }
+ ...
+//! [3]
+
+//! [4]
+class MyGLWidget : public QOpenGLWidget
+{
+ ...
+
+private:
+ QOpenGLVertexArrayObject m_vao;
+ QOpenGLBuffer m_vbo;
+ QOpenGLShaderProgram *m_program;
+ QOpenGLShader *m_shader;
+ QOpenGLTexture *m_texture;
+};
+
+MyGLWidget::MyGLWidget()
+ : m_program(0), m_shader(0), m_texture(0)
+{
+ // No OpenGL resource initialization is done here.
+}
+
+MyGLWidget::~MyGLWidget()
+{
+ // Make sure the context is current and then explicitly
+ // destroy all underlying OpenGL resources.
+ makeCurrent();
+
+ delete m_texture;
+ delete m_shader;
+ delete m_program;
+
+ m_vbo.destroy();
+ m_vao.destroy();
+
+ doneCurrent();
+}
+
+void MyGLWidget::initializeGL()
+{
+ m_vao.create();
+ if (m_vao.isCreated())
+ m_vao.bind();
+
+ m_vbo.create();
+ m_vbo.bind();
+ m_vbo.allocate(...);
+
+ m_texture = new QOpenGLTexture(QImage(...));
+
+ m_shader = new QOpenGLShader(...);
+ m_program = new QOpenGLShaderProgram(...);
+
+ ...
+}
+//! [4]
+
+//! [5]
+void MyGLWidget::initializeGL()
+{
+ // context() and QOpenGLContext::currentContext() are equivalent when called from initializeGL or paintGL.
+ connect(context(), &QOpenGLContext::aboutToBeDestroyed, this, &MyGLWidget::cleanup);
+}
+
+void MyGLWidget::cleanup()
+{
+ makeCurrent();
+ delete m_texture;
+ m_texture = 0;
+ ...
+ doneCurrent();
+}
+//! [5]
+
+//! [6]
+int main(int argc, char **argv)
+{
+ QApplication app(argc, argv);
+
+ QSurfaceFormat format;
+ format.setDepthBufferSize(24);
+ format.setStencilBufferSize(8);
+ format.setVersion(3, 2);
+ format.setProfile(QSurfaceFormat::CoreProfile);
+ QSurfaceFormat::setDefaultFormat(format);
+
+ MyWidget widget;
+ widget.show();
+
+ return app.exec();
+}
+//! [6]
diff --git a/src/opengl/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp b/src/opengl/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp
new file mode 100644
index 0000000000..bd768b1ed7
--- /dev/null
+++ b/src/opengl/doc/snippets/code/src_gui_opengl_qopenglbuffer.cpp
@@ -0,0 +1,68 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QtOpenGL/QOpenGLBuffer>
+
+namespace src_gui_opengl_qopenglbuffer {
+void wrapper() {
+
+//! [0]
+QOpenGLBuffer buffer1(QOpenGLBuffer::IndexBuffer);
+buffer1.create();
+
+QOpenGLBuffer buffer2 = buffer1;
+//! [0]
+
+
+//! [1]
+QOpenGLBuffer::release(QOpenGLBuffer::VertexBuffer);
+//! [1]
+
+} // wrapper
+} // src_gui_opengl_qopenglbuffer
diff --git a/src/opengl/doc/snippets/code/src_gui_opengl_qopengldebug.cpp b/src/opengl/doc/snippets/code/src_gui_opengl_qopengldebug.cpp
new file mode 100644
index 0000000000..241450c23a
--- /dev/null
+++ b/src/opengl/doc/snippets/code/src_gui_opengl_qopengldebug.cpp
@@ -0,0 +1,133 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QOpenGLContext>
+#include <QSurfaceFormat>
+#include <QWidget>
+#include <QtOpenGL/QOpenGLDebugLogger>
+
+namespace src_gui_opengl_qopengldebug {
+struct LogHandler : public QObject
+{
+ Q_OBJECT
+public slots:
+ static bool handleLoggedMessage() { return true; };
+};
+struct SnippetWrapper : public QObject
+{
+ Q_OBJECT
+ void wrapper1(LogHandler *receiver);
+ const QWidget *receiver;
+};
+
+void wrapper0() {
+
+//! [0]
+GLenum error = GL_NO_ERROR;
+do {
+ error = glGetError();
+ if (error != GL_NO_ERROR) {
+ // handle the error
+ }
+} while (error != GL_NO_ERROR);
+//! [0]
+
+
+//! [1]
+QSurfaceFormat format;
+// asks for a OpenGL 3.2 debug context using the Core profile
+format.setMajorVersion(3);
+format.setMinorVersion(2);
+format.setProfile(QSurfaceFormat::CoreProfile);
+format.setOption(QSurfaceFormat::DebugContext);
+
+QOpenGLContext *context = new QOpenGLContext;
+context->setFormat(format);
+context->create();
+//! [1]
+
+} // wrapper0
+
+
+void SnippetWrapper::wrapper1(LogHandler *receiver) {
+//! [2]
+QOpenGLContext *ctx = QOpenGLContext::currentContext();
+QOpenGLDebugLogger *logger = new QOpenGLDebugLogger(this);
+
+logger->initialize(); // initializes in the current context, i.e. ctx
+//! [2]
+
+
+//! [3]
+ctx->hasExtension(QByteArrayLiteral("GL_KHR_debug"));
+//! [3]
+
+
+//! [4]
+const QList<QOpenGLDebugMessage> messages = logger->loggedMessages();
+for (const QOpenGLDebugMessage &message : messages)
+ qDebug() << message;
+//! [4]
+
+
+//! [5]
+connect(logger, &QOpenGLDebugLogger::messageLogged, receiver, &LogHandler::handleLoggedMessage);
+logger->startLogging();
+//! [5]
+
+
+//! [6]
+QOpenGLDebugMessage message =
+ QOpenGLDebugMessage::createApplicationMessage(QStringLiteral("Custom message"));
+
+logger->logMessage(message);
+//! [6]
+
+} // SnippetWrapper::wrapper1
+} // src_gui_opengl_qopengldebug
diff --git a/src/opengl/doc/snippets/code/src_gui_qopenglshaderprogram.cpp b/src/opengl/doc/snippets/code/src_gui_qopenglshaderprogram.cpp
new file mode 100644
index 0000000000..131936ed3f
--- /dev/null
+++ b/src/opengl/doc/snippets/code/src_gui_qopenglshaderprogram.cpp
@@ -0,0 +1,116 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QColor>
+#include <QString>
+#include <QtOpenGL/QOpenGLShader>
+
+namespace src_gui_qopenglshaderprogram {
+QString code;
+QObject *context = nullptr;
+QRectF rect() { return QRectF(); }
+
+void wrapper() {
+//! [0]
+QOpenGLShader shader(QOpenGLShader::Vertex);
+shader.compileSourceCode(code);
+
+QOpenGLShaderProgram program(context);
+program.addShader(&shader);
+program.link();
+
+program.bind();
+//! [0]
+
+//! [1]
+program.addShaderFromSourceCode(QOpenGLShader::Vertex,
+ "attribute highp vec4 vertex;\n"
+ "uniform highp mat4 matrix;\n"
+ "void main(void)\n"
+ "{\n"
+ " gl_Position = matrix * vertex;\n"
+ "}");
+program.addShaderFromSourceCode(QOpenGLShader::Fragment,
+ "uniform mediump vec4 color;\n"
+ "void main(void)\n"
+ "{\n"
+ " gl_FragColor = color;\n"
+ "}");
+program.link();
+program.bind();
+
+int vertexLocation = program.attributeLocation("vertex");
+int matrixLocation = program.uniformLocation("matrix");
+int colorLocation = program.uniformLocation("color");
+//! [1]
+
+//! [2]
+static GLfloat const triangleVertices[] = {
+ 60.0f, 10.0f, 0.0f,
+ 110.0f, 110.0f, 0.0f,
+ 10.0f, 110.0f, 0.0f
+};
+
+QColor color(0, 255, 0, 255);
+
+QMatrix4x4 pmvMatrix;
+pmvMatrix.ortho(rect());
+
+program.enableAttributeArray(vertexLocation);
+program.setAttributeArray(vertexLocation, triangleVertices, 3);
+program.setUniformValue(matrixLocation, pmvMatrix);
+program.setUniformValue(colorLocation, color);
+
+glDrawArrays(GL_TRIANGLES, 0, 3);
+
+program.disableAttributeArray(vertexLocation);
+//! [2]
+
+} // wrapper
+} // src_gui_qopenglshaderprogram