Screenshot Command

.gitignore

@@ -1,3 +1,4 @@
 build
 ./data
 gh-pages
+*.swp

CMakeLists.txt

@@ -9,7 +9,7 @@ set(CMAKE_BUILD_TYPE "Release" CACHE STRING
 )
 
 if(NOT WIN32)
-    set(CMAKE_CXX_FLAGS "-Wall -std=c++0x" CACHE STRING "Flags used by the compiler during all build types.")
+    set(CMAKE_CXX_FLAGS "-Wall -Wno-deprecated-register -std=c++0x" CACHE STRING "Flags used by the compiler during all build types.")
 endif()
 
 project(displaz)

src/gui/PointViewerMainWindow.cpp

@@ -390,6 +390,15 @@ void PointViewerMainWindow::handleMessage(QByteArray message)
         }
         m_geometries->unloadFiles(regex);
     }
+    else if (commandTokens[0] == "SAVE_SCREENSHOT")
+    {
+        if (commandTokens.size()-1 != 1)
+        {
+            tfm::format(std::cerr, "Expected screenshot filename\n");
+            return;
+        }
+        saveScreenShot(commandTokens[1]);
+    }
     else if (commandTokens[0] == "SET_VIEW_POSITION")
     {
         if (commandTokens.size()-1 != 3)
@@ -619,6 +628,12 @@ void PointViewerMainWindow::screenShot()
     sshot.save(fileName);
 }
 
+void PointViewerMainWindow::saveScreenShot(const QString & fileName)
+{
+    QImage sshot = m_pointView->renderScreenShot();
+    sshot.save(fileName);
+    g_logger.info("Saved screenshot to file '%s'", fileName.toStdString());
+}
 
 void PointViewerMainWindow::aboutDialog()
 {

src/gui/PointViewerMainWindow.h

@@ -74,6 +74,7 @@ class PointViewerMainWindow : public QMainWindow
         void handleIpcConnection();
 
     private:
+        void saveScreenShot(const QString & fileName);
         // Gui objects
         QProgressBar* m_progressBar;
         View3D* m_pointView;

src/main.cpp

@@ -61,6 +61,7 @@ int main(int argc, char *argv[])
 
     std::string shaderName;
     std::string unloadFiles;
+    std::string saveScreenShot;
     bool noServer = false;
 
     bool clearFiles = false;
@@ -98,6 +99,7 @@ int main(int argc, char *argv[])
         "-querycursor",  &queryCursor,   "Query 3D cursor location from displaz instance",
         "-script",       &script,        "Script mode: enable several settings which are useful when calling displaz from a script:"
                                          " (a) do not wait for displaz GUI to exit before returning,",
+        "-screenshot %s", &saveScreenShot, "Remote: save current view as image to given file",
 
         "<SEPARATOR>", "\nAdditional information:",
         "-version",      &printVersion,  "Print version number",
@@ -223,6 +225,10 @@ int main(int argc, char *argv[])
     {
         channel->sendMessage(QByteArray("UNLOAD_FILES\n") + unloadFiles.c_str());
     }
+    if (!saveScreenShot.empty())
+    {
+        channel->sendMessage(QByteArray("SAVE_SCREENSHOT\n") + saveScreenShot.c_str());
+    }
     if (posX != -DBL_MAX)
     {
         channel->sendMessage("SET_VIEW_POSITION\n" +

src/render/View3D.cpp

@@ -14,6 +14,7 @@
 #include <QItemSelectionModel>
 #include <QMessageBox>
 #include <QGLFormat>
+#include <QOpenGLFramebufferObject>
 
 #include "config.h"
 #include "fileloader.h"
@@ -309,8 +310,7 @@ void View3D::initializeGL()
     setFocus();
 }
 
-
-void View3D::resizeGL(int w, int h)
+void View3D::resizeViewport(int w, int h)
 {
     //Note: This function receives "device pixel sizes" for correct OpenGL viewport setup
     //      Under OS X with retina display, this becomes important as it is 2x the width() or height()
@@ -325,6 +325,14 @@ void View3D::resizeGL(int w, int h)
     double dPR = getDevicePixelRatio();
 
     m_camera.setViewport(QRect(0,0,double(w)/dPR,double(h)/dPR));
+}
+
+void View3D::resizeGL(int w, int h)
+{
+    if (m_badOpenGL)
+        return;
+
+    resizeViewport(w, h);
 
     m_incrementalFramebuffer = allocIncrementalFramebuffer(w,h);
 
@@ -372,6 +380,23 @@ unsigned int View3D::allocIncrementalFramebuffer(int w, int h) const
     return fb;
 }
 
+void View3D::clearBuffers() const
+{
+    glClearDepth(1.0f);
+    glEnable(GL_DEPTH_TEST);
+    glDepthFunc(GL_LEQUAL);
+    glClearColor(m_backgroundColor.redF(), m_backgroundColor.greenF(),
+                 m_backgroundColor.blueF(), 1.0f);
+    if (!m_incrementalDraw)
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+}
+
+TransformState View3D::makeTransformState(int w, int h) const
+{
+    return TransformState(Imath::V2i(w, h),
+            m_camera.projectionMatrix(),
+            m_camera.viewMatrix());
+}
 
 void View3D::paintGL()
 {
@@ -397,18 +422,9 @@ void View3D::paintGL()
 
     //--------------------------------------------------
     // Draw main scene
-    TransformState transState(Imath::V2i(w, h),
-                              m_camera.projectionMatrix(),
-                              m_camera.viewMatrix());
-
-    glClearDepth(1.0f);
-    glEnable(GL_DEPTH_TEST);
-    glDepthFunc(GL_LEQUAL);
-    glClearColor(m_backgroundColor.redF(), m_backgroundColor.greenF(),
-                 m_backgroundColor.blueF(), 1.0f);
-    if (!m_incrementalDraw)
-        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    TransformState transState = makeTransformState(w, h);
 
+    clearBuffers();
     std::vector<const Geometry*> geoms = selectedGeometry();
 
     // Draw bounding boxes
@@ -498,6 +514,42 @@ void View3D::paintGL()
     glCheckError();
 }
 
+
+QImage View3D::renderScreenShot(int width, int height)
+{
+    if (m_badOpenGL)
+        return QImage();
+
+    double dPR = getDevicePixelRatio();
+    if (width < 0)
+        width = this->width();
+
+    if (height < 0)
+        height = this->height();
+
+    // Note: the reason for the following two lines and the subsequent downsampling of the
+    //       resulting image is to make the radius of rendered points consistent between the
+    //       gui and screenshot on displas with dPR != 1.
+    width *= dPR;
+    height *= dPR;
+
+    QOpenGLFramebufferObject framebuffer(QSize(width, height), QOpenGLFramebufferObject::Depth);
+    framebuffer.bind();
+    resizeViewport(width, height);
+    clearBuffers();
+
+    // Render points only
+     drawPoints(makeTransformState(width, height),
+                selectedGeometry(),
+                DBL_MAX,
+                false);
+    glFinish();
+
+    QImage img = framebuffer.toImage();
+    return img.scaledToWidth(width / dPR, Qt::SmoothTransformation);
+}
+
+
 void View3D::drawMeshes(const TransformState& transState,
                         const std::vector<const Geometry*>& geoms) const
 {

src/render/View3D.h

@@ -52,6 +52,9 @@ class View3D : public QGLWidget
         QItemSelectionModel* selectionModel() { return m_selectionModel; }
         void setSelectionModel(QItemSelectionModel* selectionModel);
 
+        // Render pointcloud to offscreen buffer of given size and return as a QImage.
+        // Negative dimensions are replaced with current gui 3d viewport size.
+        QImage renderScreenShot(int width = -1, int height = -1);
     public slots:
         /// Set the backgroud color
         void setBackground(QColor col);
@@ -85,6 +88,8 @@ class View3D : public QGLWidget
         void geometryInserted(const QModelIndex&, int firstRow, int lastRow);
 
     private:
+        void resizeViewport(int w, int h);
+        void clearBuffers() const;
         double getDevicePixelRatio();
         unsigned int allocIncrementalFramebuffer(int w, int h) const;
 
@@ -101,6 +106,8 @@ class View3D : public QGLWidget
                              const std::vector<const Geometry*>& geoms,
                              double quality, bool incrementalDraw);
 
+        TransformState makeTransformState(int w, int h) const;
+
         void drawMeshes(const TransformState& transState,
                         const std::vector<const Geometry*>& geoms) const;