Use framebuffer object as fallback for off-screen rendering

src/Gui/Thumbnail.cpp

@@ -29,6 +29,7 @@
 # include <QByteArray>
 # include <QDateTime>
 # include <QImage>
+# include <QGLFramebufferObject>
 #endif
 
 #include "Thumbnail.h"
@@ -85,24 +86,17 @@ void Thumbnail::SaveDocFile (Base::Writer &writer) const
     if (!this->viewer)
         return;
     QImage img;
-    try {
-        this->viewer->savePicture(this->size, this->size, View3DInventorViewer::Current, img);
-        // Alternative way of off-screen rendering
-#if 0
-        QGLFramebufferObject fbo(this->size, this->size,QGLFramebufferObject::Depth);
-        fbo.bind();
-        glEnable(GL_DEPTH_TEST);
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-        glDepthRange(0.1,1.0);
-        glEnable(GL_LINE_SMOOTH);
-        SoGLRenderAction gl(SbViewportRegion(this->size,this->size));
-        gl.apply(this->viewer->getSceneManager()->getSceneGraph());
-        fbo.release();
-        img = fbo.toImage();
-#endif
+    if (App::GetApplication().GetParameterGroupByPath
+        ("User parameter:BaseApp/Preferences/Document")->GetBool("DisablePBuffers",false)) {
+        this->createThumbnailFromFramebuffer(img);
     }
-    catch (...) {
-        return; // offscreen rendering failed
+    else {
+        try {
+            this->viewer->savePicture(this->size, this->size, View3DInventorViewer::Current, img);
+        }
+        catch (...) {
+            this->createThumbnailFromFramebuffer(img);
+        }
     }
 
     QPixmap px = Gui::BitmapFactory().pixmap(App::Application::Config()["AppIcon"].c_str());
@@ -126,3 +120,11 @@ void Thumbnail::SaveDocFile (Base::Writer &writer) const
 void Thumbnail::RestoreDocFile(Base::Reader &reader)
 {
 }
+
+void Thumbnail::createThumbnailFromFramebuffer(QImage& img) const
+{
+    // Alternative way of off-screen rendering
+    QGLFramebufferObject fbo(this->size, this->size,QGLFramebufferObject::Depth);
+    this->viewer->renderToFramebuffer(&fbo);
+    img = fbo.toImage();
+}

src/Gui/Thumbnail.h

@@ -27,6 +27,8 @@
 #include <Base/Persistence.h>
 #include <QUrl>
 
+class QImage;
+
 namespace Gui {
 class View3DInventorViewer;
 
@@ -53,6 +55,9 @@ public:
     void RestoreDocFile(Base::Reader &reader);
     //@}
 
+private:
+    void createThumbnailFromFramebuffer(QImage&) const;
+
 private:
     QUrl uri;
     View3DInventorViewer* viewer;

src/Gui/View3DInventor.cpp

@@ -27,6 +27,7 @@
 # include <QAction>
 # include <QApplication>
 # include <QFileInfo>
+# include <QGLFramebufferObject>
 # include <QKeyEvent>
 # include <QEvent>
 # include <QDropEvent>
@@ -483,12 +484,38 @@ void View3DInventor::print(QPrinter* printer)
     QImage img;
     QPainter p(printer);
     QRect rect = printer->pageRect();
-    _viewer->savePicture(rect.width(), rect.height(), View3DInventorViewer::White, img);
+
+    if (App::GetApplication().GetParameterGroupByPath
+        ("User parameter:BaseApp/Preferences/Document")->GetBool("DisablePBuffers",false)) {
+        previewFromFramebuffer(rect, img);
+    }
+    else {
+        try {
+            _viewer->savePicture(rect.width(), rect.height(), View3DInventorViewer::White, img);
+        }
+        catch (...) {
+            previewFromFramebuffer(rect, img);
+        }
+    }
+
     p.drawImage(0,0,img);
     p.end();
 #endif
 }
 
+void View3DInventor::previewFromFramebuffer(const QRect& rect, QImage& img)
+{
+    QGLFramebufferObject fbo(rect.width(), rect.height(), QGLFramebufferObject::Depth);
+    const SbColor col = _viewer->getBackgroundColor();
+    bool on = _viewer->hasGradientBackground();
+    _viewer->setBackgroundColor(SbColor(1.0f,1.0f,1.0f));
+    _viewer->setGradientBackground(false);
+    _viewer->renderToFramebuffer(&fbo);
+    _viewer->setBackgroundColor(col);
+    _viewer->setGradientBackground(on);
+    img = fbo.toImage();
+}
+
 // **********************************************************************************
 
 bool View3DInventor::onMsg(const char* pMsg, const char** ppReturn)

src/Gui/View3DInventor.h

@@ -127,6 +127,7 @@ protected:
     void focusInEvent     (QFocusEvent     * e);
     void customEvent      (QEvent          * e);
     void contextMenuEvent (QContextMenuEvent*e);
+    void previewFromFramebuffer(const QRect&, QImage&);
 
     /// handle to the viewer parameter group
     ParameterGrp::handle hGrp;

src/Gui/View3DInventorViewer.cpp

@@ -430,6 +430,11 @@ void View3DInventorViewer::setGradientBackground(bool on)
         backgroundroot->removeChild(pcBackGround);
 }
 
+bool View3DInventorViewer::hasGradientBackground() const
+{
+    return (backgroundroot->findChild(pcBackGround) != -1);
+}
+
 void View3DInventorViewer::setGradientBackgroundColor(const SbColor& fromColor,
                                                       const SbColor& toColor)
 {
@@ -577,7 +582,6 @@ void View3DInventorViewer::savePicture(const char* filename, int w, int h,
             throw Base::Exception("Offscreen rendering failed");
         // set matrix for miba
         renderer._Matrix = camera->getViewVolume().getMatrix();
-        //bool ok = renderer.writeToImageFile(filename, filetypeextension);
         renderer.writeToImageFile(filename, comment);
         root->unref();
     }
@@ -941,6 +945,8 @@ void View3DInventorViewer::renderToFramebuffer(QGLFramebufferObject* fbo)
 {
     this->glLockNormal();
     fbo->bind();
+    int width = fbo->size().width();
+    int height = fbo->size().height();
 
     glDisable(GL_TEXTURE_2D);
     glEnable(GL_LIGHTING);
@@ -948,12 +954,13 @@ void View3DInventorViewer::renderToFramebuffer(QGLFramebufferObject* fbo)
     glEnable(GL_LINE_SMOOTH);
 
     const SbColor col = this->getBackgroundColor();
-    glClearColor(col[0], col[1], col[2], 0.0f);
+    glViewport(0, 0, width, height);
+    glClearColor(col[0], col[1], col[2], 1.0f);
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
     glDepthRange(0.1,1.0);
 
-    SoGLRenderAction gl(SbViewportRegion(fbo->size().width(),fbo->size().height()));
+    SoGLRenderAction gl(SbViewportRegion(width, height));
     gl.apply(this->backgroundroot);
     gl.apply(this->getSceneManager()->getSceneGraph());
     gl.apply(this->foregroundroot);

src/Gui/View3DInventorViewer.h

@@ -269,6 +269,7 @@ public:
     void viewSelection();
 
     void setGradientBackground(bool b);
+    bool hasGradientBackground() const;
     void setGradientBackgroundColor(const SbColor& fromColor,
                                     const SbColor& toColor);
     void setGradientBackgroundColor(const SbColor& fromColor,

src/Gui/View3DPy.cpp

@@ -26,6 +26,8 @@
 #ifndef __InventorAll__
 # include "InventorAll.h"
 # include <sstream>
+# include <QImage>
+# include <QGLFramebufferObject>
 #endif
 
 
@@ -556,6 +558,37 @@ Py::Object View3DInventorPy::isAnimationEnabled(const Py::Tuple& args)
     return Py::Boolean(ok ? true : false);
 }
 
+void View3DInventorPy::createImageFromFramebuffer(int backgroundType, int width, int height, QImage& img)
+{
+    QGLFramebufferObject fbo(width, height, QGLFramebufferObject::Depth);
+    const SbColor col = _view->getViewer()->getBackgroundColor();
+    bool on = _view->getViewer()->hasGradientBackground();
+
+    switch(backgroundType){
+        case 0: // Current
+            break;
+        case 1: // Black
+            _view->getViewer()->setBackgroundColor(SbColor(0.0f,0.0f,0.0f));
+            _view->getViewer()->setGradientBackground(false);
+            break;
+        case 2: // White
+            _view->getViewer()->setBackgroundColor(SbColor(1.0f,1.0f,1.0f));
+            _view->getViewer()->setGradientBackground(false);
+            break;
+        case 3: // Transparent
+            _view->getViewer()->setBackgroundColor(SbColor(1.0f,1.0f,1.0f));
+            _view->getViewer()->setGradientBackground(false);
+            break;
+        default:
+            break;
+    }
+
+    _view->getViewer()->renderToFramebuffer(&fbo);
+    _view->getViewer()->setBackgroundColor(col);
+    _view->getViewer()->setGradientBackground(on);
+    img = fbo.toImage();
+}
+
 Py::Object View3DInventorPy::saveImage(const Py::Tuple& args)
 {
     char *cFileName,*cImageType="Current",*cComment="$MIBA";
@@ -587,24 +620,23 @@ Py::Object View3DInventorPy::saveImage(const Py::Tuple& args)
     else 
         throw Py::Exception("Parameter 4 have to be (Current|Black|White|Transparent)");
 #endif
+    if (App::GetApplication().GetParameterGroupByPath
+        ("User parameter:BaseApp/Preferences/Document")->GetBool("DisablePBuffers",false)) {
+        QImage img;
+        createImageFromFramebuffer(t, w, h, img);
+        img.save(QString::fromUtf8(cFileName));
+        return Py::None();
+    }
 
     try {
-        QColor c;
         _view->getViewer()->savePicture(cFileName,w,h,t,cComment);
         return Py::None();
     }
-    catch (const Base::Exception& e) {
-        Base::Console().Log("Try disabling the use of pbuffers, set the environment variables\n"
-                            "COIN_GLXGLUE_NO_PBUFFERS=1\n"
-                            "COIN_GLXGLUE_NO_GLX13_PBUFFERS=1\n"
-                            "and re-run the application.\n");
-        throw Py::Exception(e.what());
-    }
-    catch (const std::exception& e) {
-        throw Py::Exception(e.what());
-    }
-    catch(...) {
-        throw Py::Exception("Unknown C++ exception");
+    catch (const Base::Exception&) {
+        QImage img;
+        createImageFromFramebuffer(t, w, h, img);
+        img.save(QString::fromUtf8(cFileName));
+        return Py::None();
     }
 }
 

src/Gui/View3DPy.h

@@ -28,6 +28,7 @@
 #include <CXX/Extensions.hxx>
 
 class SoEventCallback;
+class QImage;
 
 namespace Gui {
 
@@ -102,6 +103,7 @@ private:
     typedef PyObject* (*method_varargs_handler)(PyObject *_self, PyObject *_args);
     static method_varargs_handler pycxx_handler;
     static PyObject *method_varargs_ext_handler(PyObject *_self, PyObject *_args);
+    void createImageFromFramebuffer(int backgroundType, int width, int height, QImage&);
 
 private:
     std::list<PyObject*> callbacks;