rem: WidthOfScreen(DefaultScreenOfDisplay(dpy))/2, HeightOfScreen(DefaultScreenOfDisplay(dpy))/2);
add: (WidthOfScreen(scr)-WMWidgetWidth(panel->win))/2, (HeightOfScreen(scr)-WMWidgetHeight(panel->win))/2);
context: ShowTexturePanel(TexturePanel *panel){    Display *dpy = WMScreenDisplay(WMWidgetScreen(panel->win));    WMSetWindowUPosition(panel->win, 			 WidthOfScreen(DefaultScreenOfDisplay(dpy))/2,			 HeightOfScreen(DefaultScreenOfDisplay(dpy))/2);    WMMapWidget(panel->win);}