qt: More error handling and tweaking to opengl 3 renderer

src/qt/qt_opengloptions.cpp

@@ -172,7 +172,7 @@ OpenGLOptions::addShader(const QString &path)
     if (!shader->addShaderFromSourceCode(QOpenGLShader::Vertex, version_line % "\n#extension GL_ARB_shading_language_420pack : enable\n" % "\n#define VERTEX\n" % shader_text))
         throw_shader_error(tr("Error compiling vertex shader in file \"%1\""));
 
-    if (!shader->addShaderFromSourceCode(QOpenGLShader::Fragment, version_line % "\n#extension GL_ARB_shading_language_420pack : enable\n"  "\n#define FRAGMENT\n" % shader_text))
+    if (!shader->addShaderFromSourceCode(QOpenGLShader::Fragment, version_line % "\n#extension GL_ARB_shading_language_420pack : enable\n" % "\n#define FRAGMENT\n" % shader_text))
         throw_shader_error(tr("Error compiling fragment shader in file \"%1\""));
 
     if (!shader->link())

src/qt/qt_openglrenderer.cpp

@@ -18,8 +18,8 @@
 #include <QMessageBox>
 #include <QOpenGLShaderProgram>
 #include <QOpenGLTexture>
+#include <QStringBuilder>
 #include <QSurfaceFormat>
-#include <QOpenGLTexture>
 
 #include <cmath>
 
@@ -44,18 +44,13 @@ OpenGLRenderer::OpenGLRenderer(QWidget *parent)
 
     format.setProfile(QSurfaceFormat::OpenGLContextProfile::CoreProfile);
     format.setMajorVersion(3);
-    format.setMinorVersion(0);
+    format.setMinorVersion(2);
+
     if (QOpenGLContext::openGLModuleType() == QOpenGLContext::LibGLES)
         format.setRenderableType(QSurfaceFormat::OpenGLES);
 
     setFormat(format);
 
-    context = new QOpenGLContext(this);
-
-    context->setFormat(format);
-
-    context->create();
-
     parentWidget = parent;
 
     source.setRect(0, 0, INIT_WIDTH, INIT_HEIGHT);
@@ -108,21 +103,22 @@ OpenGLRenderer::event(QEvent *event)
 void
 OpenGLRenderer::initialize()
 {
-    if (!context->makeCurrent(this)) {
-        /* TODO: This could be done much better */
-        QMessageBox::critical((QWidget *) qApp->findChild<QWindow *>(), tr("Error initializing OpenGL"), tr("Error setting OpenGL context. Falling back to software rendering."));
-        context->doneCurrent();
-        isFinalized   = true;
-        isInitialized = true;
-        emit errorInitializing();
-        return;
-    }
+    try {
+        context = new QOpenGLContext(this);
+
+        context->setFormat(format());
+
+        if (!context->create())
+            throw opengl_init_error(tr("Couldn't create OpenGL context."));
+
+        if (!context->makeCurrent(this))
+            throw opengl_init_error(tr("Couldn't switch to OpenGL context."));
 
         initializeOpenGLFunctions();
 
-    setupExtensions();
+        initializeExtensions();
 
-    setupBuffers();
+        initializeBuffers();
 
         /* Vertex, texture 2d coordinates and color (white) making a quad as triangle strip */
         const GLfloat surface[] = {
@@ -160,12 +156,30 @@ OpenGLRenderer::initialize()
         glViewport(
             destination.x(),
             destination.y(),
-        destination.width(),
-        destination.height());
+            destination.width() * devicePixelRatio(),
+            destination.height() * devicePixelRatio());
+
+        GLenum error = glGetError();
+        if (error != GL_NO_ERROR)
+            throw opengl_init_error(tr("OpenGL initialization failed. Error %1.").arg(error));
 
         isInitialized = true;
 
         emit initialized();
+
+    } catch (const opengl_init_error &e) {
+        /* Mark all buffers as in use */
+        for (auto &flag : buf_usage)
+            flag.test_and_set();
+
+        QMessageBox::critical((QWidget *) qApp->findChild<QWindow *>(), tr("Error initializing OpenGL"), e.what() % tr("\nFalling back to software rendering."));
+
+        context->doneCurrent();
+        isFinalized   = true;
+        isInitialized = true;
+
+        emit errorInitializing();
+    }
 }
 
 void
@@ -174,6 +188,8 @@ OpenGLRenderer::finalize()
     if (isFinalized)
         return;
 
+    renderTimer->stop();
+
     context->makeCurrent(this);
 
     if (hasBufferStorage)
@@ -203,7 +219,7 @@ OpenGLRenderer::getOptions(QWidget *parent)
 }
 
 void
-OpenGLRenderer::setupExtensions()
+OpenGLRenderer::initializeExtensions()
 {
 #ifndef NO_BUFFER_STORAGE
     if (context->hasExtension("GL_ARB_buffer_storage")) {
@@ -215,7 +231,7 @@ OpenGLRenderer::setupExtensions()
 }
 
 void
-OpenGLRenderer::setupBuffers()
+OpenGLRenderer::initializeBuffers()
 {
     glGenBuffers(1, &unpackBufferID);
 
@@ -232,6 +248,9 @@ OpenGLRenderer::setupBuffers()
         /* Fallback; create our own buffer. */
         unpackBuffer = malloc(BUFFERBYTES * BUFFERCOUNT);
 
+        if (unpackBuffer == nullptr)
+            throw opengl_init_error(tr("Allocating memory for unpack buffer failed."));
+
         glBufferData(GL_PIXEL_UNPACK_BUFFER, BUFFERBYTES * BUFFERCOUNT, NULL, GL_STREAM_DRAW);
     }
 }

src/qt/qt_openglrenderer.hpp

@@ -32,6 +32,7 @@
 #endif
 
 #include <atomic>
+#include <stdexcept>
 #include <tuple>
 #include <vector>
 
@@ -90,8 +91,8 @@ private:
     void *unpackBuffer = nullptr;
 
     void initialize();
-    void setupExtensions();
-    void setupBuffers();
+    void initializeExtensions();
+    void initializeBuffers();
     void applyOptions();
     void applyShader(const OpenGLShaderPass &shader);
     bool notReady() const { return !isInitialized || isFinalized; }
@@ -107,4 +108,12 @@ private slots:
     void updateOptions(OpenGLOptions *newOptions);
 };
 
+class opengl_init_error : public std::runtime_error {
+public:
+    opengl_init_error(const QString &what)
+        : std::runtime_error(what.toStdString())
+    {
+    }
+};
+
 #endif

src/qt/qt_rendererstack.cpp

@@ -272,6 +272,7 @@ RendererStack::createRenderer(Renderer renderer)
                 });
                 connect(hw, &OpenGLRenderer::errorInitializing, [=]() {
                     /* Renderer could initialize, fallback to software. */
+                    imagebufs = {};
                     endblit();
                     QTimer::singleShot(0, this, [this]() { switchRenderer(Renderer::Software); });
                 });
@@ -299,7 +300,7 @@ RendererStack::createRenderer(Renderer renderer)
 void
 RendererStack::blit(int x, int y, int w, int h)
 {
-    if ((w <= 0) || (h <= 0) || (w > 2048) || (h > 2048) || (buffer32 == NULL) || std::get<std::atomic_flag *>(imagebufs[currentBuf])->test_and_set()) {
+    if ((w <= 0) || (h <= 0) || (w > 2048) || (h > 2048) || (buffer32 == NULL) || imagebufs.empty() || std::get<std::atomic_flag *>(imagebufs[currentBuf])->test_and_set()) {
         video_blit_complete();
         return;
     }