From 611558d877a9ee4448b30e5443e3025c6235daaf Mon Sep 17 00:00:00 2001 From: Laszlo Agocs Date: Sat, 2 Aug 2014 19:42:15 +0200 Subject: Modernize the OpenGL examples Change them to use QOpenGLWidget and QOpenGLTexture. Advocate also the usage of VBOs. Hopeless examples, that rely on the fixed pipeline and will not compile or work in ES and dynamic builds, are moved to a "legacy" directory. The documentation pages for these are removed. This long due change avoids the confusion newcomers experience when trying to get started with Qt 5 and OpenGL. hellowindow's behavior is changed to open a single window only by default. The old default behavior, that opened three windows on platforms that supported both MultipleWindows & ThreadedOpenGL, can be requested by passing --multiple. --single is removed since it is the default now. This plays much nicer with drivers that have issues with threading. In addition, say hello to hellogl2. This is the old hellogl example updated to use QOpenGLWidget and OpenGL 2. It also has a mainwindow with multiple (un)dockable widgets containing the OpenGL widgets. This helps testing the behavior when the top-level of the QOpenGLWidget changes and provides a very important example of how to do proper resource management in this case. (must use aboutToBeDestroyed() of the context, since the context goes away and is replaced by a new one on every dock/undock) As a bonus, the logo is now real 3D, no more orthographic nonsense. Launch with --multisample to request 4x MSAA. Launch with --coreprofile to request 3.2 Core. In this particular example the shaders are present in both versions and there is a VAO so the application is functional with core profile contexts. Change-Id: Id780a80cb0708ef164cc172450ed74050f065596 Reviewed-by: Gunnar Sletta --- examples/opengl/cube/geometryengine.cpp | 46 ++++++++++++++++----------------- 1 file changed, 22 insertions(+), 24 deletions(-) (limited to 'examples/opengl/cube/geometryengine.cpp') diff --git a/examples/opengl/cube/geometryengine.cpp b/examples/opengl/cube/geometryengine.cpp index 0a342130848..618a080c370 100644 --- a/examples/opengl/cube/geometryengine.cpp +++ b/examples/opengl/cube/geometryengine.cpp @@ -1,6 +1,6 @@ /**************************************************************************** ** -** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies). +** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies). ** Contact: http://www.qt-project.org/legal ** ** This file is part of the QtCore module of the Qt Toolkit. @@ -49,29 +49,27 @@ struct VertexData QVector2D texCoord; }; +//! [0] GeometryEngine::GeometryEngine() + : indexBuf(QOpenGLBuffer::IndexBuffer) { -} - -GeometryEngine::~GeometryEngine() -{ - glDeleteBuffers(2, vboIds); -} - -void GeometryEngine::init() -{ - initializeGLFunctions(); + initializeOpenGLFunctions(); -//! [0] // Generate 2 VBOs - glGenBuffers(2, vboIds); - -//! [0] + arrayBuf.create(); + indexBuf.create(); // Initializes cube geometry and transfers it to VBOs initCubeGeometry(); } +GeometryEngine::~GeometryEngine() +{ + arrayBuf.destroy(); + indexBuf.destroy(); +} +//! [0] + void GeometryEngine::initCubeGeometry() { // For cube we would need only 8 vertices but we have to @@ -133,21 +131,21 @@ void GeometryEngine::initCubeGeometry() //! [1] // Transfer vertex data to VBO 0 - glBindBuffer(GL_ARRAY_BUFFER, vboIds[0]); - glBufferData(GL_ARRAY_BUFFER, 24 * sizeof(VertexData), vertices, GL_STATIC_DRAW); + arrayBuf.bind(); + arrayBuf.allocate(vertices, 24 * sizeof(VertexData)); // Transfer index data to VBO 1 - glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vboIds[1]); - glBufferData(GL_ELEMENT_ARRAY_BUFFER, 34 * sizeof(GLushort), indices, GL_STATIC_DRAW); + indexBuf.bind(); + indexBuf.allocate(indices, 34 * sizeof(GLushort)); //! [1] } //! [2] -void GeometryEngine::drawCubeGeometry(QGLShaderProgram *program) +void GeometryEngine::drawCubeGeometry(QOpenGLShaderProgram *program) { // Tell OpenGL which VBOs to use - glBindBuffer(GL_ARRAY_BUFFER, vboIds[0]); - glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vboIds[1]); + arrayBuf.bind(); + indexBuf.bind(); // Offset for position quintptr offset = 0; @@ -155,7 +153,7 @@ void GeometryEngine::drawCubeGeometry(QGLShaderProgram *program) // Tell OpenGL programmable pipeline how to locate vertex position data int vertexLocation = program->attributeLocation("a_position"); program->enableAttributeArray(vertexLocation); - glVertexAttribPointer(vertexLocation, 3, GL_FLOAT, GL_FALSE, sizeof(VertexData), (const void *)offset); + program->setAttributeBuffer(vertexLocation, GL_FLOAT, offset, 3, sizeof(VertexData)); // Offset for texture coordinate offset += sizeof(QVector3D); @@ -163,7 +161,7 @@ void GeometryEngine::drawCubeGeometry(QGLShaderProgram *program) // Tell OpenGL programmable pipeline how to locate vertex texture coordinate data int texcoordLocation = program->attributeLocation("a_texcoord"); program->enableAttributeArray(texcoordLocation); - glVertexAttribPointer(texcoordLocation, 2, GL_FLOAT, GL_FALSE, sizeof(VertexData), (const void *)offset); + program->setAttributeBuffer(texcoordLocation, GL_FLOAT, offset, 2, sizeof(VertexData)); // Draw cube geometry using indices from VBO 1 glDrawElements(GL_TRIANGLE_STRIP, 34, GL_UNSIGNED_SHORT, 0); -- cgit v1.2.3