[Scummvm-devel] State of the SCUMM: Please read.

[Marcus Comstedt]

Max Horn <max at quendi.de> writes:

> The show_overlay() and grab_clear_overlay() functions are responible
> for this. In the SDL implementation, show_overlay() at the end calls
> clear_overlay(). This function in turn has only one responsibility:
> clearing the overlay, by setting it to the content of the game screen,
> converted to 16 bit.

Ah.  Ok.  That was a rather odd semantics for "clearing" the overlay.
:-)  I would probably have called it "copy_background_to_overlay()" or
something.


> That all depends on how your backend implements shaking. IMHO there is
> no need for us to standarize on this, I recommend that you just do it
> as it suits you best. When it comes to the NewGUI code, all it sees is
> a buffer of 320x200 (or 320x240 in Zak) into which it writes, at
> certain positions. How you display that, shifted or not, is up to you.

It also sees mouse events, and if the coordinates of the mouse events
doesn't match the coordinates _in the overlay_ of the pixel you
intended to click at, it might be a problem.  By having the overlay
shake with the background, the coordinates become the same so problems
can be avoided.


  // Marcus