# The Shortcuts

Key filtering - the ability of "interface element" to act as a different tool in case when Ctrl, Alt and Shift keys being hold during mouse click. 

Usually Ctrl key will mean "Add", "Alt" key will mean "Exclude", "Shift" key will mean "Next object".

## Mouse shortcuts

**Right mouse (when) click drag** - Pan. \
**Wheel up** - zoom in. \
**Wheel down** - zoom out. \
**Left mouse click drag over selection** - move selected objects (can be combined with WSAD screen control). \
**Left mouse click drag over edge of selected resizable object** - resize selected object (can be combined with WSAD screen control). \
**Left mouse click drag** - selection region drag (can be combined with WSAD screen control). \
**Ctrl + Left mouse click drag** - add objects to selection by dragging selection region (can be combined with WSAD screen control). \
**Alt + Left mouse click drag** - subtract objects from selection by dragging selection region (can be combined with WSAD screen control). \
**Shift + Left mouse click drag over selection** - select object behind selected object.

## Keyboard shortcuts

**Ctrl + Z** - undo. \
**Ctrl + Y** - redo. \
**Delete / Backspace** - delete selected objects. \
**H** - mirrors selected objects horizontally. \
**V** - mirrors selected objects vertically. \
**W/S/A/D** - move screen in 4 directions (can be mentioned as WSAD screen control). \
**Shift + W/S/A/D** - move screen in 4 directions faster. \
**Q** - toggle additional panels auto-hide to see error code. \
**Ctrl + C** - copy selected objects to "Primary" clipboard. \
**Ctrl + V** - paste objects from "Primary" clipboard.

## Secondary clipboard (new editor only)

{% hint style="info" %}
Surprisingly, eric added this options so we can copy source from other's open source maps easier and faster.
{% endhint %}

Ctrl + N - copy selected objects to "Secondary N" clipboard. \
N - paste objects from "Secondary N" clipboard. 

{% hint style="info" %}
Which N is 0\~9. In mathematical speaking, $${N | 0 <= N <= 9, N ∈Z+}$$&#x20;
{% endhint %}