implemented savefile screenshot feature

src/common/image.cpp

@@ -418,3 +418,43 @@ bool CImage::SavePNG(const std::string& fileName)
     return true;
 }
 
+void CImage::SetDataPixels(void *pixels){
+
+    if (m_data != nullptr){
+
+        if (m_data->surface != nullptr)
+        {
+            if ( m_data->surface->pixels != nullptr ){
+                unsigned int* pixels = static_cast<unsigned int*>(m_data->surface->pixels);
+                delete [] pixels;
+                m_data->surface->pixels = nullptr;
+            }
+        }
+    }
+
+    m_data->surface->pixels = pixels;
+}
+
+void CImage::flipVertical(){
+
+    SDL_Surface* result = SDL_CreateRGBSurface(m_data->surface->flags, m_data->surface->w, m_data->surface->h,
+        m_data->surface->format->BytesPerPixel * 8, m_data->surface->format->Rmask, m_data->surface->format->Gmask,
+        m_data->surface->format->Bmask, m_data->surface->format->Amask);
+    
+    assert(result != nullptr);
+ 
+    Uint8* srcPixels = static_cast<Uint8*> (m_data->surface->pixels);
+    Uint8* resultPixels = static_cast<Uint8*> (result->pixels);
+ 
+    Uint32 pitch = m_data->surface->pitch;
+    Uint32 pxLength = pitch*m_data->surface->h;
+ 
+    for(int line = 0; line < m_data->surface->h; ++line) {
+        Uint32 pos = line * pitch;
+        memcpy(&resultPixels[pos], &srcPixels[(pxLength-pos)-pitch], pitch);
+    }
+    
+    SDL_FreeSurface(m_data->surface);
+
+    m_data->surface = result;                                
+}

src/common/image.h

@@ -109,6 +109,12 @@ public:
     //! Returns the last error
     std::string GetError();
 
+    //! Flips the image vertically
+    void flipVertical();
+    
+    //! sets/replaces the pixels from the surface 
+    void SetDataPixels(void *pixels);
+
 private:
     //! Blit to new RGBA surface with given size
     void BlitToNewRGBASurface(int width, int height);

src/graphics/core/device.h

@@ -400,6 +400,9 @@ public:
     virtual void SetFillMode(FillMode mode) = 0;
     //! Returns the current fill mode
     virtual FillMode GetFillMode() = 0;
+
+    //! Returns the pixels of the entire screen
+    virtual void* GetFrameBufferPixels()const = 0;
 };
 
 

src/graphics/engine/engine.cpp

@@ -424,9 +424,20 @@ void CEngine::FrameUpdate()
 
 bool CEngine::WriteScreenShot(const std::string& fileName, int width, int height)
 {
-    // TODO write screenshot: not very important for now
+    void *pixels = m_device->GetFrameBufferPixels();
-    GetLogger()->Debug("CEngine::WriteSceenShot(): stub!\n");
+    CImage img({width,height});
-    return true;
+
+    img.SetDataPixels(pixels);
+    img.flipVertical();
+
+    if ( img.SavePNG(fileName.c_str()) ){
+       GetLogger()->Info("Save SceenShot Saved Successfully!\n");
+       return true;
+    }
+    else{
+       GetLogger()->Error("%s!\n",img.GetError().c_str());
+       return false;
+    }   
 }
 
 bool CEngine::GetPause()

src/graphics/opengl/gldevice.cpp

@@ -1791,6 +1791,23 @@ FillMode CGLDevice::GetFillMode()
     return FILL_POINT;
 }
 
+void* CGLDevice::GetFrameBufferPixels()const{
+
+    SDL_Surface* surface = SDL_GetVideoSurface();
+
+    assert(surface != nullptr);
+
+    GLubyte* pixels = new GLubyte [4 * surface->h * surface->w];
+    
+    glReadPixels(0,0,surface->w,surface->h,GL_RGBA,GL_UNSIGNED_BYTE,pixels);
+
+    unsigned int* p = static_cast<unsigned int*> ( static_cast<void*>(pixels) );
+
+    for (int i = 0; i < surface->h * surface->w; ++i)
+        p[i] |= 0xFF000000;
+
+    return static_cast<void*>(p);
+}
 
 } // namespace Gfx
 

src/graphics/opengl/gldevice.h

@@ -188,6 +188,8 @@ public:
     virtual void SetFillMode(FillMode mode) ;
     virtual FillMode GetFillMode();
 
+    virtual void* GetFrameBufferPixels()const;
+
 private:
     //! Updates internal modelview matrix
     void UpdateModelviewMatrix();

src/ui/maindialog.cpp

@@ -2076,8 +2076,9 @@ bool CMainDialog::EventProcess(const Event &event)
             m_shotDelay --;
             if ( m_shotDelay == 0 )
             {   
-                m_engine->WriteScreenShot(m_shotName, 320, 240);
+                Math::IntPoint screenSize = m_app->GetVideoConfig().size;
-                //?             m_engine->WriteScreenShot(m_shotName, 160, 120);
+
+                m_engine->WriteScreenShot(m_shotName, screenSize.x, screenSize.y);
             }
         }