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(VI) Frame control & locking the screen while drawing: screensync, cls, screenlock, screenunlock

Hiya everybody!


Take a look at the code of the day:

Let me explain the new keywords used:
  • screensync is the key to take the number of frames per second under control because this instruction waits until next refresh of the screen, usually 60 times per second known as 60 fps. After this we will draw our screen.
  • cls to CLear the Screen and draw from zero the new state of the game.
  • screenlock to lock the screen to hide it while we are drawing.
  • screenunlock to unlock the screen to show the new drawed screen.
Is very important to respect that we have to draw inmediately after the screensync and remember that between screenlock and screenunlock you have to draw, nothing else to do this part of the code as fast as possible.

How is the structure? more and more accurate every time:
  • DESCRIPTION
  • DECLARATIONS
  • INITIALIZATIONS
  • GAME LOOP
    • INPUT
    • DO UPDATE
    • DRAW
      • screensync
      • screenlock
      • cls
      • ...
      • screenunlock
    • FREE UP CPU TIME
      • sleep 1,1
  • ENDING
This is enough by now, we are ready to see in the next entry how to control and move the white square.

Contact me for any question and tell me your feedback, see you!

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