Cursor modes

Cursor modes are a type of game mechanic in Terraria. Auto Select and Smart Cursor are the two cursor modes implemented to make using tools and placing objects more convenient.

Auto Select
Auto Select will automatically select an item to use, depending on where the cursor is pointed. The item does not need to be in the hot bar. By default, Auto Select is activated by pressing Shift on PC, R3 on PS3/PS4, or pressing down the right thumbstick on Xbox 360.

A Flare Gun without Flares won't be selected. Nor will other light sources such as candles. If more than one item is equally appropriate it will normally select the first one in your inventory. And if the preferred item is unavailable it will usually fall back to something else.

Smart Cursor
Smart Cursor selects a target based on the active item. By default, it is toggled on and off by pressing Ctrl. There is also an option in General Settings to make it last only while the key is held down. Smart Cursor mode is indicated by a slightly wider cursor, and the tile targeted is shown with a yellow box. On the Mobile version, Smart Cursor can be used with the right joystick.

Using Smart Cursor with a multi-function tool, like Drax or a Hamaxe, may have unexpected results. These tools will behave as an axe by default, meaning they always target a tree if one is in range.