[SOLVED] Drawing onto the background of a GUI

[Monsieur OUXX]

Hi,

In my 32-bit game,  created two GUIs with those features:
GUI #1 :
  - background color: 0
  - background color number: 0;0;0
  - background image: 666 (this is a picture that's entirely transparent -- it's all pink)

GUI #2:
  - background color: 0
  - background color number: 0;0;0
  - background image: 777 (this is a picture that is almost entirely transparent, with just a few colored pixels in the top-left corner)

Note: In the code, I have a variable _renderingGui that can point to either GUI#1 or GUI#2 depending on the needs of the test.

At the very beginning of the game execution, I do this once, to take a screenshot of the GUI background:

Code: AGS

   DynamicSprite* bgSnapshot; //global variable, used later

  DynamicSprite* sprite = DynamicSprite.CreateFromExistingSprite(_renderingGui.BackgroundGraphic);
  DrawingSurface *surface = sprite.GetDrawingSurface();
  if (bgSnapshot == null) { //very first time
    bgSnapshot =        DynamicSprite.CreateFromDrawingSurface(
                          surface, 0, 0,
                          surface.Width,  surface.Height
                          );
  }

Then, in repeatedly_execute_always, I do this:

Code: AGS

    DynamicSprite* sprite; //global variable

    ...

    sprite = DynamicSprite.CreateFromExistingSprite(_renderingGui.BackgroundGraphic);
    DrawingSurface *surface = sprite.GetDrawingSurface();

    redrawBackground(surface); //this draws [i]bgSnapshot[/i] back into [i]surface[/i]
    DrawStuff(surface); //this draws shapes and stuff onto [i]surface[/i]

   surface.Release();
   _renderingGui.BackgroundGraphic = sprite.Graphic;

I observe a very weird behaviour that I can't explain:

- When I run this code with _renderingGui being GUI#1, then I can see all the stuff that gets drawn in DrawStuff(); Apparently, the fact that the background image of the GUI is completely transparent has something to do with it: I'm almost certain that nothing gets drawn during redrawBackground(), because when I draw more and more stuff in DrawStuff() at each loop, the stuff drawn in the previous loop is still visible below.
- When I run this code with _renderingGui being GUI#2, then I can only see the background image of the gui. All the stuff that gets drawn on top of it in DrawStuff() does not appear.


Anybody has an idea?

[Monsieur OUXX]

Ok I think that the issue rests with : sprite = DynamicSprite.CreateFromExistingSprite(_renderingGui.BackgroundGraphic);

Because of that, AGS creates a very small sprite (because th eoriginal background image is tiny), and then no matter what I draw, it's always outside the surface, so I don't see it.
My complteley transparent sprite was much bigger, so I could see what was drawn into its surface.

I'll replace the line with sprite = DynamicSprite.Create(_renderingGui.Width,  _renderingGui.Height);


Solved.