Memory Mapped Device Layer

Implemented MemMapDev layer, added User Manual and Programmers
Reference.

GraphDisp.h

@@ -0,0 +1,72 @@
+#ifndef GRAPHDISP_H
+#define GRAPHDISP_H
+
+/*
+ * Rudimentary emulation of generic raster graphics RGB display device.
+ */
+
+#include <thread>
+#include <SDL.h>
+
+using namespace std; 
+
+namespace MKBasic {
+
+const int GRAPHDISP_MAXW = 640;	// "real" display width or maximum virtual width
+const int GRAPHDISP_MAXH = 400;	// "real" display width or maximum virtual height
+
+class GraphDisp {
+
+	public:
+
+		bool mContLoop = true;
+		bool mMainLoopActive = false;		
+
+		GraphDisp();
+		GraphDisp(int width, int height);
+		~GraphDisp();
+		void Start(GraphDisp *pgd);
+		void Stop();
+		void SetPixel(int x, int y);
+		void ErasePixel(int x, int y);
+		void DrawLine(int x1, int y1, int x2, int y2);
+		void EraseLine(int x1, int y1, int x2, int y2);
+		void SetBgColor(int r, int g, int b);
+		void SetFgColor(int r, int g, int b);
+		void Update();
+		void ReadEvents();
+		void ClearScreen();
+		//void MainLoop();
+		bool IsMainLoopActive();
+
+	private:
+
+		int	mWidth = 320;			// virtual display width
+		int mHeight = 200;		// virtual display height
+		int mPixelSizeX = 2;	// virtual pixel width
+		int mPixelSizeY = 2;	// virtual pixel height
+		int mWinPosX = 0;			// SDL window position coordinate X
+		int mWinPosY = 0;			// SDL window position coordinate Y
+		int mBgRgbR = 0;			// bg color, RGB red intensity
+		int mBgRgbG = 0;			// bg color, RGB green intensity
+		int mBgRgbB = 0;			// bg color, RGB blue intensity
+		int mFgRgbR = 0xFF;		// fg color, RGB red intensity
+		int mFgRgbG = 0xFF;		// fg color, RGB green intensity
+		int mFgRgbB = 0xFF;		// fg color, RGB blue intensity		
+		SDL_Window *mpWindow = NULL;
+		SDL_Surface *mpSurface = NULL;
+		SDL_Renderer *mpRenderer = NULL;
+		thread mMainLoopThread;
+
+		void Initialize();
+		void UpdateSurface();
+		void Clear();
+		void GetDesktopResolution(int& horizontal, int& vertical);
+		void DrawLine(int x1, int y1, int x2, int y2, bool draworerase);
+		void RenderPixel(int x, int y, bool set);		
+
+}; // class GraphDisp
+
+} // namespace MKBasic
+
+#endif