no copyright line shown if texture not shown due to wrong mode

rogueviz/ads/ds-game.cpp

@@ -488,6 +488,7 @@ void view_ds_game() {
 
   sphereflip = hv ? Id : sphereflipped() ? MirrorZ : Id;
 
+  copyright_shown = "";
   if(!hv) draw_textures();
 
   if(1) {

rogueviz/ads/ds-texture.cpp

@@ -178,7 +178,6 @@ void draw_texture(texture_to_use& tu) {
 
 void draw_textures() {
   pick_textures();
-  copyright_shown = "";
   for(auto& tu: textures_to_use)
     if(current.shift > tu.from && current.shift < tu.to)
       draw_texture(tu);