Attempt xcb image put.

README.md

@@ -33,7 +33,7 @@ sudo apt-get install libpng-dev
 #### Window rendering
 
 ```bash
-sudo apt-get install libwayland-dev wayland-protocols libx11-dev libxkbcommon-dev libx11-xcb-dev
+sudo apt-get install libwayland-dev wayland-protocols libx11-dev libxkbcommon-dev libx11-xcb-dev libxcb-image0-dev 
 ```
 
 We need to generate suitable xdg shell c code for wayland:

src/image/Image.cpp

@@ -19,7 +19,7 @@ Image<T>::~Image()
 template<typename T>
 void Image<T>::initialize()
 {
-    mData = std::vector<T>(getBytesPerRow()*mHeight, 0);
+    mData = std::vector<T>(getBytesPerRow()*mHeight, 10);
 }
 
 template<typename T>

src/image/Image.h

@@ -29,12 +29,28 @@ public:
     void setBitDepth(unsigned bitDepth);
     void setNumChannels(unsigned numChannels);
 
-private:
     void initialize();
 
+    const T* getDataPtr() const
+    {
+        return mData.data();
+    }
+
+    const std::vector<T>& getDataRef() const
+    {
+        return mData;
+    }
+
+    std::vector<T> getData() const
+    {
+        return mData;
+    }
+
+private:
+
     unsigned mWidth{1};
     unsigned mHeight{1};
     unsigned mBitDepth{8};
-    unsigned mNumChannels{1};
+    unsigned mNumChannels{4};
     std::vector<T> mData;
 };

src/windows/CMakeLists.txt

@@ -17,7 +17,7 @@ if(UNIX)
             ui_interfaces/x11/XcbKeyboard.cpp
             ui_interfaces/x11/GlxInterface.cpp
             )
-        list(APPEND platform_LIBS ${X11_LIBRARIES} ${X11_xcb_LIB} ${X11_X11_xcb_LIB} ${X11_xkbcommon_LIB})
+        list(APPEND platform_LIBS ${X11_LIBRARIES} ${X11_xcb_LIB} ${X11_X11_xcb_LIB} ${X11_xkbcommon_LIB} libxcb-image.so)
         list(APPEND X11_INCLUDE_DIRS ${X11_xkbcommon_INCLUDE_PATH})         
     else()
         message(STATUS "x11 development headers not found - skipping support")   

src/windows/ui_interfaces/x11/XcbImage.h

@@ -1,6 +1,47 @@
 #pragma once
 
+#include <xcb/xcb_image.h>
+
+#include "Window.h"
+#include "XcbWindow.h"
+
 class XcbImage
 {
+public:
+    XcbImage(xcb_connection_t* connection, mt::Window* window, xcb_screen_t* screen)
+    {
+        mPixmap = xcb_generate_id(connection);
+        auto hwnd = dynamic_cast<XcbWindow*>(window->GetPlatformWindow())->getHandle();
+        const auto w = window->GetWidth();
+        const auto h = window->GetHeight();
+        xcb_create_pixmap(connection, screen->root_depth, mPixmap, hwnd, w, h);
+    }
 
+    void update(mt::Window* window, xcb_screen_t* screen, xcb_connection_t* connection, xcb_gcontext_t gc)
+    {
+        if (!mXImage)
+        {
+            auto backing_image = window->getBackingImage();
+
+            const auto w = window->GetWidth();
+            const auto h = window->GetHeight();
+
+            //auto data = const_cast<unsigned char*>(backing_image->getDataPtr());
+            auto data = backing_image->getData();
+            unsigned char* converted = &data[0];
+            mXImage = xcb_image_create_native(connection, w, h, XCB_IMAGE_FORMAT_Z_PIXMAP, screen->root_depth, converted, w*h*4, converted);
+
+            xcb_image_put(connection, mPixmap, gc, mXImage, 0, 0, 0);
+            //xcb_image_destroy(mXImage);
+        }
+    }
+
+    xcb_pixmap_t getPixMap() const
+    {
+        return mPixmap;
+    }
+
+private:
+    xcb_pixmap_t mPixmap{0};
+    xcb_image_t* mXImage{nullptr};
 };

src/windows/ui_interfaces/x11/XcbWindow.cpp

@@ -5,13 +5,13 @@
 #include "XcbScreen.h"
 #include "XcbImage.h"
 #include "Screen.h"
+#include "ImagePrimitives.h"
 
 #include <xcb/xcb.h>
 
 XcbWindow::XcbWindow(mt::Window* window, int hwnd, xcb_connection_t* connection)
     : IPlatformWindow(window),
       mHandle(hwnd),
-      mBackingImage(std::make_unique<XcbImage>()),
       mConnection(connection)
 {
 
@@ -61,10 +61,25 @@ void XcbWindow::show() const
 void XcbWindow::paint(mt::Screen* screen)
 {
     auto xcb_screen = dynamic_cast<XcbScreen*>(screen->GetPlatformScreen());
+
+    if (!mBackingImage)
+    {
+        mBackingImage = std::make_unique<XcbImage>(mConnection, mWindow, xcb_screen->GetNativeScreen());
+    }
+
+    auto backing_image = mWindow->getBackingImage();
+    backing_image->initialize();
+    //ImagePrimitives::drawCheckerboard(const_cast<unsigned char*>(backing_image->getDataPtr()), backing_image->getWidth(), backing_image->getHeight(), 0);
+
+    mBackingImage->update(mWindow, xcb_screen->GetNativeScreen(), mConnection,  xcb_screen->GetGraphicsContext());
+
+    xcb_copy_area(mConnection, mBackingImage->getPixMap(), mHandle, xcb_screen->GetGraphicsContext(), 0, 0 ,0 , 0, backing_image->getWidth(), backing_image->getHeight());
+/*
     for(const auto& layer : mWindow->GetLayers())
     {
         XcbLayerInterface::AddLayer(mConnection, xcb_screen->GetNativeScreen(), mHandle, xcb_screen->GetGraphicsContext(), layer);
     }
+    */
 }
 
 void XcbWindow::clear() const