The majority of the main window is taken up by the drawing area, which is where you'll be creating your masterpieces. This is where you'll edit the points (or nodes) that make up your shapes.
Below the drawing area are some status fields that provide general information about the current image, such as where the origin and mouse cursor are currently located, and the current level of magnification.
Features and Controls
Guides
The drawing area provides several guides to help you position and place shapes and their points within the image. These include a red X that marks the origin of the image (ie, the upper left corner), grid lines that let you position things at specific pixel locations, and a semi-transparent rectangle that indicates where the image's background is located.
Neither the X nor the grid lines are part of your image; they simply exist to help you orient yourself within the drawing area. You may also choose to disable the grid lines via an option in the main window's View menu.
As for the background, you can control its color and size using the Image Details Dialog, found under Image Options. How this information is used when exporting image depends on whether you're exporting a vector or raster image.
Lastly, if a shape is currently selected, its nodes and origin will be overlaid over everything else. The origin is represented by a white diamond, while the nodes can either be a square or circle, depending on their type. Their color is also determined by their state: inactive nodes are white, the selected node is blue, and the node following the selected node in sequence is red. More information about these shapes and colors can be found in the next section.
Basic Controls
Dragging with the middle button held down will always scroll the drawing area. This is the only way the middle button is used, so don't be worried about middle clicking by accident.
On the other hand, which Tool is active determines what the left and right mouse buttons do. Each tool also has a unique cursor assigned to it, so you can see what tool you're using just by checking your mouse cursor.
The available tools, and their various functions, are listed in the table below.
Tool
Cursor
Function(s)
Edit Nodes Tool
The default tool, this allows you to add a new node at a given location. A shape's nodes are listed in a specific sequence, so the new node will either be appended to the end of the list, or, if a node is currently selected, the new one will be inserted after it.
This is also why two nodes are highlighted when one is selected - it allows you to clearly see where the new node will be added.
Left-Clicking when the mouse is over a node will select that node, allowing you to change where the next node will be inserted, and you can also drag the selected node to a new location.
Left-Clicking anywhere else in the drawing area will add a new node to the current shape. If no shape is currently active, a new shape will be created and the new node added to it.
Right-Clicking on a node will toggle it between straight and curved states.
Right-Clicking anywhere else in the drawing area will deselect the current shape, allowing you to start creating a new shape without leaving the drawing area.
Select Nodes Tool
This tool allows you to select and move existing nodes. Since this tool cannot add new nodes, you may want to switch to it once you're done drawing the initial shape.
Left-Clicking on a node will simply select it, but Left-Clicking anywhere else will begin dragging the selection rectangle. When you let go of the left mouse button, every node within the selection rectangle will be selected simultaniously. You can then use the left mouse button to drag them, the DELETE key to remove them, or the Node menu to align them in a column or row.
Right-Clicking on a node will toggle it between straight and curved states. Right-Clicking anywhere else will do nothing.
Move Shape Tool
Should you ever want to move an entire shape, use this tool. When this tool is enabled, dragging with the Left mouse button will move the currently active shape.
Alternatively, you can also move an entire shape using the Select Nodes Tool - simply select all of the shape's nodes and then move them. However, if you've assigned the origin point for this shape, dragging the nodes like this does not update it, which may not be the desired result.
Rotate Shape Tool
Drag anywhere with the Left mouse button to rotate your shape.
To constrain the rotation to a limited selection of angles, hold the CTRL key while you drag.
Set Origin Tool
Simply Left-Click somewhere on the window to assign the location of the shape's origin point. By default, a shape's origin point will automatically stay in the center of the shape.
The origin point is primarily used as the point the shape is rotated around, so if you're not interested in rotating the shape, this isn't really necessary.
Other Controls
Unfortunately, some features had to be delegated to the keyboard. These features are described here.
Holding SHIFT while left-clicking on the window will attempt to select the shape under your cursor. This works regardless of the tool you have active, and it also respects the layering of the shapes in your work.
If you want to remove a node or nodes from a Path or Line, select them and press DELETE on your keyboard. This will remove every selected node permanently, stitching the other nodes in the sequence together as if the missing nodes never existed.