Tetris: render after creating a new piece

src/tetris/background.h

@@ -26,7 +26,7 @@ void DrawBoard() {
   channels_set_fg(&channels, 0x00b040);
   channels_set_bg_alpha(&channels, CELL_ALPHA_TRANSPARENT);
   if(!board_->double_box(0, channels, BOARD_HEIGHT - 1, BOARD_WIDTH * 2 - 1, NCBOXMASK_TOP)){
-    throw TetrisNotcursesErr("rounded_box()");
+    throw TetrisNotcursesErr("double_box()");
   }
   channels_set_fg_alpha(&channels, CELL_ALPHA_TRANSPARENT);
   board_->set_base(channels, 0, "");

src/tetris/newpiece.h

@@ -32,11 +32,14 @@ std::unique_ptr<ncpp::Plane> NewPiece() {
     for(size_t i = 0 ; i < strlen(t->texture) ; ++i){
       if(t->texture[i] == '*'){
         if(n->putstr(y, x, "██") < 0){
-          return NULL;
+          throw TetrisNotcursesErr("putstr()");
         }
       }
       y += ((x = ((x + 2) % cols)) == 0);
     }
   }
+  if(notcurses_render(nc_)){
+    throw TetrisNotcursesErr("render()");
+  }
   return n;
 }