fix: use glReadnPixels for X11 copying to be more memory safe

src/WallpaperEngine/Application/CWallpaperApplication.cpp

@@ -219,7 +219,7 @@ void CWallpaperApplication::setupProperties () {
         this->setupPropertiesForProject (info);
 }
 
-void CWallpaperApplication::takeScreenshot (const std::filesystem::path& filename) {
+void CWallpaperApplication::takeScreenshot (const std::filesystem::path& filename) const {
     // this should be getting called at the end of the frame, so the right thing should be bound already
     const int width = this->m_renderContext->getOutput ().getFullWidth ();
     const int height = this->m_renderContext->getOutput ().getFullHeight ();
@@ -238,7 +238,6 @@ void CWallpaperApplication::takeScreenshot (const std::filesystem::path& filenam
         const uint8_t* pixel = buffer;
 
         // read the viewport data into the pixel buffer
-        glPixelStorei (GL_PACK_ALIGNMENT, 1);
         glReadnPixels (viewport->viewport.x, viewport->viewport.y, viewport->viewport.z, viewport->viewport.w, GL_RGB,
                       GL_UNSIGNED_BYTE, bufferSize, buffer);
 

src/WallpaperEngine/Application/CWallpaperApplication.h

@@ -106,7 +106,7 @@ class CWallpaperApplication {
      *
      * @param filename
      */
-    void takeScreenshot (const std::filesystem::path& filename);
+    void takeScreenshot (const std::filesystem::path& filename) const;
 
     /** The application context that contains the current app settings */
     CApplicationContext& m_context;

src/WallpaperEngine/Render/Drivers/CGLFWOpenGLDriver.cpp

@@ -132,9 +132,16 @@ void CGLFWOpenGLDriver::dispatchEventQueue () {
         this->getApp ().update (viewport);
 
     // read the full texture into the image
-    if (this->m_output->haveImageBuffer ())
+    if (this->m_output->haveImageBuffer ()) {
-        glReadPixels (0, 0, this->m_output->getFullWidth (), this->m_output->getFullHeight (), GL_BGRA,
+        glReadnPixels (0, 0, this->m_output->getFullWidth (), this->m_output->getFullHeight (), GL_BGRA,
-                      GL_UNSIGNED_BYTE, this->m_output->getImageBuffer ());
+                      GL_UNSIGNED_BYTE, this->m_output->getImageBufferSize(), this->m_output->getImageBuffer ());
+
+        GLenum error = glGetError();
+
+        if (error != GL_NO_ERROR) {
+            sLog.exception("OpenGL error when reading texture ", error);
+        }
+    }
 
     // TODO: FRAMETIME CONTROL SHOULD GO BACK TO THE CWALLPAPAERAPPLICATION ONCE ACTUAL PARTICLES ARE IMPLEMENTED
     // TODO: AS THOSE, MORE THAN LIKELY, WILL REQUIRE OF A DIFFERENT PROCESSING RATE

src/WallpaperEngine/Render/Drivers/Output/CGLFWWindowOutput.cpp

@@ -56,6 +56,10 @@ void* CGLFWWindowOutput::getImageBuffer () const {
     return nullptr;
 }
 
+uint32_t CGLFWWindowOutput::getImageBufferSize () const {
+    return 0;
+}
+
 void CGLFWWindowOutput::updateRender () const {
     if (this->m_context.settings.render.mode != Application::CApplicationContext::NORMAL_WINDOW)
         return;

src/WallpaperEngine/Render/Drivers/Output/CGLFWWindowOutput.h

@@ -13,6 +13,7 @@ class CGLFWWindowOutput final : public COutput {
     bool renderMultiple () const override;
     bool haveImageBuffer () const override;
     void* getImageBuffer () const override;
+    uint32_t getImageBufferSize () const override;
     void updateRender () const override;
 
   private:

src/WallpaperEngine/Render/Drivers/Output/COutput.h

@@ -38,6 +38,7 @@ class COutput {
     virtual bool haveImageBuffer () const = 0;
     const std::map<std::string, COutputViewport*>& getViewports () const;
     virtual void* getImageBuffer () const = 0;
+    virtual uint32_t getImageBufferSize () const = 0;
     virtual void updateRender () const = 0;
 
   protected:

src/WallpaperEngine/Render/Drivers/Output/CWaylandOutput.cpp

@@ -51,4 +51,8 @@ void* CWaylandOutput::getImageBuffer () const {
     return nullptr;
 }
 
+uint32_t CWaylandOutput::getImageBufferSize () const {
+    return 0;
+}
+
 void CWaylandOutput::updateRender () const {}

src/WallpaperEngine/Render/Drivers/Output/CWaylandOutput.h

@@ -24,6 +24,7 @@ class CWaylandOutput final : public COutput {
     bool renderMultiple () const override;
     bool haveImageBuffer () const override;
     void* getImageBuffer () const override;
+    uint32_t getImageBufferSize () const override;
     void updateRender () const override;
 
   private:

src/WallpaperEngine/Render/Drivers/Output/CX11Output.cpp

@@ -83,6 +83,10 @@ bool CX11Output::haveImageBuffer () const {
     return true;
 }
 
+uint32_t CX11Output::getImageBufferSize () const {
+    return this->m_imageSize;
+}
+
 void CX11Output::loadScreenInfo () {
     // reset the viewports
     this->m_viewports.clear ();
@@ -163,6 +167,7 @@ void CX11Output::loadScreenInfo () {
     // set the window background as our pixmap
     XSetWindowBackgroundPixmap (this->m_display, this->m_root, this->m_pixmap);
     // allocate space for the image's data
+    this->m_imageSize = this->m_fullWidth * this->m_fullHeight * 4;
     this->m_imageData = new char [this->m_fullWidth * this->m_fullHeight * 4];
     // create an image so we can copy it over
     this->m_image = XCreateImage (this->m_display, CopyFromParent, 24, ZPixmap, 0, this->m_imageData, this->m_fullWidth,

src/WallpaperEngine/Render/Drivers/Output/CX11Output.h

@@ -21,6 +21,7 @@ class CX11Output final : public COutput {
     bool renderMultiple () const override;
     bool haveImageBuffer () const override;
     void* getImageBuffer () const override;
+    uint32_t getImageBufferSize () const override;
     void updateRender () const override;
 
   private:
@@ -32,6 +33,7 @@ class CX11Output final : public COutput {
     Window m_root;
     GC m_gc;
     char* m_imageData;
+    uint32_t m_imageSize;
     XImage* m_image;
     std::vector<COutputViewport*> m_screens;
 };