From 464d713c2affcf7d8acb3403c9bd33bca673fb56 Mon Sep 17 00:00:00 2001 From: Matt Williams Date: Sun, 23 Mar 2014 12:16:02 +0000 Subject: [PATCH] Remove usage of QOpenGLFunctions and use GLEW instead. Qt's OpenGL interface was causing problems on Windows since it doesn't mix well with ANGLE. Relates to issue #50. --- examples/Basic/CMakeLists.txt | 8 +++- examples/Basic/OpenGLWidget.cpp | 79 +++++++++++++++------------------ examples/Basic/OpenGLWidget.h | 5 +-- 3 files changed, 43 insertions(+), 49 deletions(-) diff --git a/examples/Basic/CMakeLists.txt b/examples/Basic/CMakeLists.txt index 66515549..a7b81ff5 100644 --- a/examples/Basic/CMakeLists.txt +++ b/examples/Basic/CMakeLists.txt @@ -32,13 +32,17 @@ SET(INC_FILES OpenGLWidget.h ) +add_definitions(-DGLEW_STATIC) + #"Sources" and "Headers" are the group names in Visual Studio. #They may have other uses too... SOURCE_GROUP("Sources" FILES ${SRC_FILES}) SOURCE_GROUP("Headers" FILES ${INC_FILES}) +FIND_PACKAGE(OpenGL REQUIRED) + #Tell CMake the paths for OpenGL and for PolyVox (which is just relative to our current location) -INCLUDE_DIRECTORIES(${PolyVoxCore_BINARY_DIR}/include ${PolyVoxCore_SOURCE_DIR}/include) +INCLUDE_DIRECTORIES(${PolyVoxCore_BINARY_DIR}/include ${PolyVoxCore_SOURCE_DIR}/include ${GLEW_SOURCE_DIR}) LINK_DIRECTORIES(${PolyVoxCore_BINARY_DIR}) #Build @@ -46,7 +50,7 @@ ADD_EXECUTABLE(BasicExample ${SRC_FILES}) IF(MSVC) SET_TARGET_PROPERTIES(BasicExample PROPERTIES COMPILE_FLAGS "/W4 /wd4127") ENDIF(MSVC) -TARGET_LINK_LIBRARIES(BasicExample Qt5::OpenGL PolyVoxCore) +TARGET_LINK_LIBRARIES(BasicExample glew Qt5::OpenGL ${OPENGL_gl_LIBRARY} PolyVoxCore) SET_PROPERTY(TARGET BasicExample PROPERTY FOLDER "Examples") #Install - Only install the example in Windows diff --git a/examples/Basic/OpenGLWidget.cpp b/examples/Basic/OpenGLWidget.cpp index 37f972af..5b93b08e 100644 --- a/examples/Basic/OpenGLWidget.cpp +++ b/examples/Basic/OpenGLWidget.cpp @@ -11,7 +11,6 @@ OpenGLWidget::OpenGLWidget(QWidget *parent) :QGLWidget(parent) ,m_xRotation(0) ,m_yRotation(0) - ,gl(nullptr) { } @@ -22,63 +21,57 @@ void OpenGLWidget::setSurfaceMeshToRender(const PolyVox::SurfaceMeshglGenVertexArrays(1, &vertexArrayObject); - gl->glBindVertexArray(vertexArrayObject); + glGenVertexArrays(1, &vertexArrayObject); + glBindVertexArray(vertexArrayObject); //The GL_ARRAY_BUFFER will contain the list of vertex positions - gl->glGenBuffers(1, &vertexBuffer); - gl->glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer); - gl->glBufferData(GL_ARRAY_BUFFER, vecVertices.size() * sizeof(PositionMaterial), vecVertices.data(), GL_STATIC_DRAW); + glGenBuffers(1, &vertexBuffer); + glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer); + glBufferData(GL_ARRAY_BUFFER, vecVertices.size() * sizeof(PositionMaterial), vecVertices.data(), GL_STATIC_DRAW); //and GL_ELEMENT_ARRAY_BUFFER will contain the indices - gl->glGenBuffers(1, &indexBuffer); - gl->glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer); - gl->glBufferData(GL_ELEMENT_ARRAY_BUFFER, vecIndices.size() * sizeof(uint32_t), vecIndices.data(), GL_STATIC_DRAW); + glGenBuffers(1, &indexBuffer); + glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer); + glBufferData(GL_ELEMENT_ARRAY_BUFFER, vecIndices.size() * sizeof(uint32_t), vecIndices.data(), GL_STATIC_DRAW); //We need to tell OpenGL how to understand the format of the vertex data - gl->glEnableVertexAttribArray(0); //We're talking about shader attribute '0' - gl->glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(PositionMaterial), 0); //take the first 3 floats from every sizeof(decltype(vecVertices)::value_type) + glEnableVertexAttribArray(0); //We're talking about shader attribute '0' + glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(PositionMaterial), 0); //take the first 3 floats from every sizeof(decltype(vecVertices)::value_type) - gl->glBindVertexArray(0); + glBindVertexArray(0); noOfIndices = vecIndices.size(); //Save this for the call to glDrawElements later } void OpenGLWidget::initializeGL() { - //'gl' will give us access to all the OpenGL functions - gl = context()->contextHandle()->versionFunctions(); - if(!gl) + GLenum err = glewInit(); + if (GLEW_OK != err) { - std::cerr << "Could not obtain required OpenGL context version" << std::endl; - exit(EXIT_FAILURE); - } - if(!gl->initializeOpenGLFunctions()) - { - std::cerr << "Could not initialise OpenGL functions" << std::endl; - exit(EXIT_FAILURE); + /* Problem: glewInit failed, something is seriously wrong. */ + std::cout << "GLEW Error: " << glewGetErrorString(err) << std::endl; } //Print out some information about the OpenGL implementation. std::cout << "OpenGL Implementation Details:" << std::endl; - if(gl->glGetString(GL_VENDOR)) - std::cout << "\tGL_VENDOR: " << gl->glGetString(GL_VENDOR) << std::endl; - if(gl->glGetString(GL_RENDERER)) - std::cout << "\tGL_RENDERER: " << gl->glGetString(GL_RENDERER) << std::endl; - if(gl->glGetString(GL_VERSION)) - std::cout << "\tGL_VERSION: " << gl->glGetString(GL_VERSION) << std::endl; - if(gl->glGetString(GL_SHADING_LANGUAGE_VERSION)) - std::cout << "\tGL_SHADING_LANGUAGE_VERSION: " << gl->glGetString(GL_SHADING_LANGUAGE_VERSION) << std::endl; + if(glGetString(GL_VENDOR)) + std::cout << "\tGL_VENDOR: " << glGetString(GL_VENDOR) << std::endl; + if(glGetString(GL_RENDERER)) + std::cout << "\tGL_RENDERER: " << glGetString(GL_RENDERER) << std::endl; + if(glGetString(GL_VERSION)) + std::cout << "\tGL_VERSION: " << glGetString(GL_VERSION) << std::endl; + if(glGetString(GL_SHADING_LANGUAGE_VERSION)) + std::cout << "\tGL_SHADING_LANGUAGE_VERSION: " << glGetString(GL_SHADING_LANGUAGE_VERSION) << std::endl; //Set up the clear colour - gl->glClearColor(0.0f, 0.0f, 0.0f, 0.0f); - gl->glClearDepth(1.0f); + glClearColor(0.0f, 0.0f, 0.0f, 0.0f); + glClearDepth(1.0f); - gl->glEnable(GL_CULL_FACE); - gl->glEnable(GL_DEPTH_TEST); - gl->glDepthMask(GL_TRUE); - gl->glDepthFunc(GL_LEQUAL); - gl->glDepthRange(0.0, 1.0); + glEnable(GL_CULL_FACE); + glEnable(GL_DEPTH_TEST); + glDepthMask(GL_TRUE); + glDepthFunc(GL_LEQUAL); + glDepthRange(0.0, 1.0); if(!shader.addShaderFromSourceCode(QOpenGLShader::Vertex, R"( #version 140 @@ -144,7 +137,7 @@ void OpenGLWidget::initializeGL() void OpenGLWidget::resizeGL(int w, int h) { //Setup the viewport - gl->glViewport(0, 0, w, h); + glViewport(0, 0, w, h); auto aspectRatio = w / (float)h; float zNear = 1.0; @@ -161,7 +154,7 @@ void OpenGLWidget::resizeGL(int w, int h) void OpenGLWidget::paintGL() { //Clear the screen - gl->glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); + glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); QMatrix4x4 modelToWorldMatrix{}; modelToWorldMatrix.rotate(m_xRotation, 0, 1, 0); //rotate around y-axis @@ -172,15 +165,15 @@ void OpenGLWidget::paintGL() shader.setUniformValue("modelToWorldMatrix", modelToWorldMatrix); //Update to the latest camera matrix - gl->glBindVertexArray(vertexArrayObject); + glBindVertexArray(vertexArrayObject); - gl->glDrawElements(GL_TRIANGLES, noOfIndices, GL_UNSIGNED_INT, 0); + glDrawElements(GL_TRIANGLES, noOfIndices, GL_UNSIGNED_INT, 0); - gl->glBindVertexArray(0); + glBindVertexArray(0); shader.release(); - GLenum errCode = gl->glGetError(); + GLenum errCode = glGetError(); if(errCode != GL_NO_ERROR) { std::cerr << "OpenGL Error: " << errCode << std::endl; diff --git a/examples/Basic/OpenGLWidget.h b/examples/Basic/OpenGLWidget.h index 08ff3cc7..1b201803 100644 --- a/examples/Basic/OpenGLWidget.h +++ b/examples/Basic/OpenGLWidget.h @@ -26,12 +26,10 @@ distribution. #include "PolyVoxCore/SurfaceMesh.h" -#include +#include "glew/glew.h" #include #include -#include -#include class OpenGLWidget : public QGLWidget { @@ -60,7 +58,6 @@ private: GLuint vertexArrayObject; QOpenGLShaderProgram shader; - QOpenGLFunctions_3_1* gl; //Mouse data QPoint m_LastFrameMousePos;