I am trying to draw a Checkerboard pattern on a lcd using a GUI library called emWin. I have actually managed to draw it using the following code. But having these many loops in the program body for a single task, that too in the internal flash of the Microcontroller is not a good idea. Those who have not worked with emWin, I will try and explain a few things before we go for actual logic. GUI_REST is a structure which id define source files of emWin and I am blind to it. Rect, REct2,Rec3.. and so on till Rect10 are objects. Elements of the Rect array are {x0,y0,x1,y1}, where x0,y0 are starting locations of rectangle in X-Y plane and x1, y1 are end locations of Rectangle in x-Y plane. So, Rect={0,0,79,79} is a rectangle starts at top left of the LCD and is upto (79,79), so its a square basically. The function GUI_setBkColor(int color); sets the color of the background. The function GUI_setColor(int color); sets the color of the foreground. GUI_WHITE and DM_CHECKERBOARD_COLOR are two color values, #defineed GUI_FillRectEx(&Rect); will draw the Rectangle. The code below works fine but I want to make it smarter. GUI_RECT Rect = {0, 0, 79, 79}; GUI_RECT Rect2 = {80, 0, 159, 79}; GUI_RECT Rect3 = {160, 0, 239, 79}; GUI_RECT Rect4 = {240, 0, 319, 79}; GUI_RECT Rect5 = {320, 0, 399, 79}; GUI_RECT Rect6 = {400, 0, 479, 79}; GUI_RECT Rect7 = {480, 0, 559, 79}; GUI_RECT Rect8 = {560, 0, 639, 79}; GUI_RECT Rect9 = {640, 0, 719, 79}; GUI_RECT Rect10 = {720, 0, 799, 79}; WM_SelectWindow(Win_DM_Main); GUI_SetBkColor(GUI_BLACK); GUI_Clear(); for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect); Rect.y0 += 80; Rect.y1 += 80; } /* for(j=0,j<11;j++) { for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect); Rect.y0 += 80; Rect.y1 += 80; } Rect.x0 += 80; Rect.x1 += 80; } */ for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect2); Rect2.y0 += 80; Rect2.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect3); Rect3.y0 += 80; Rect3.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect4); Rect4.y0 += 80; Rect4.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect5); Rect5.y0 += 80; Rect5.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect6); Rect6.y0 += 80; Rect6.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect7); Rect7.y0 += 80; Rect7.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect8); Rect8.y0 += 80; Rect8.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(GUI_WHITE); else GUI_SetColor(DM_CHECKERBOARD_COLOR); GUI_FillRectEx(&Rect9); Rect9.y0 += 80; Rect9.y1 += 80; } for(i = 0; i < 6; i++) { if(i%2 == 0) GUI_SetColor(DM_CHECKERBOARD_COLOR); else GUI_SetColor(GUI_WHITE); GUI_FillRectEx(&Rect10); Rect10.y0 += 80; Rect10.y1 += 80; }