[Freeciv-Dev] Re: non-rectangular flag scaling

[Vasco Alexandre Da Silva Costa <vasc@xxxxxxxxxxxxxx>]

On Sun, 2 Sep 2001, Raimar Falke wrote:

> On Sun, Sep 02, 2001 at 07:42:05PM +0200, Karl-Ingo Friese wrote:
> > On Sat, 1 Sep 2001, Karl-Ingo Friese wrote:
> > 
> > > On Sat, 1 Sep 2001, Raimar Falke wrote:
> > > > The attached patch should work but doesn't. It works half if the
> > > > clipping is disabled. This leaves however black borders. Any ideas?
> > > >
> > > >         Raimar
> > >
> > > I will have a look at it lateron today.
> > >
> > > Ingo
> > 
> > I rewrote the crop & scale part so that is able to deal
> > with non-rectangular flags now (which do not even have
> > to begin in the first row/column of pixels). Instead of
> > the combined crop & scale action before, I splited it
> > into first calculating the bounding box of the non-masked
> > pixels, croping it to the new dimensions and finaly scale
> > the croped image.
> 
> This was also my plan.
> 
> > ................
> > ................
> > ......X.........         ...X...
> > .....XXX........    crop     ..XXX..    scale    .X.
> > ....XXXXX.......   ----->    .XXXXX.   ------->  XXX
> > ...XXXXXXX......         XXXXXXX             .X.
> > ......X.........         ...X...
> > ................
> > ................
> > 
> > 
> > Raimar: I took your function and just changed it that way that
> > it looks now for the first/last column that contains a non
> > masked pixel (and same for the rows of course). The "old"
> > code parsed only the first row/column for start and end.
> 
> I thought I have allready changed this.
> 
> > The result looks a little better; what is left to do now is
> > mask out the black pixels. I will have to look-up gtk-manuals
> > for this.
> 
> My idea was: making a white picture, drawing the flag on the white
> picture (includes cropping)(with the mask set as the clipping mask the
> white background is untouched outside the flag) and than scale it.

You would have to take care with this since on certain themes the
background may not be white, it may not even be a solid color at all.

---
Vasco Alexandre da Silva Costa @ Instituto Superior Tecnico, Lisboa