+ int xsn_alpha_dx = (gfx.mouse_y > xsn.area_ysize - xsn.max_height ?
+ (xsn.alpha > XSN_ALPHA_VISIBLE ? -1 : 0) :
+ (xsn.alpha < XSN_ALPHA_DEFAULT ? +1 : 0));
+
+ if (xsn_alpha_dx != 0)
+ {
+ xsn.alpha += xsn_alpha_dx;
+
+ SDLSetAlpha(xsn.bitmap->surface_masked, TRUE, xsn.alpha);
+
+ SDLFreeBitmapTextures(xsn.bitmap);
+ SDLCreateBitmapTextures(xsn.bitmap);
+ }
+