Both of these items only need to be in inventory to be used and have toggle switches in the top left to turn on and off. The toggles can be bound to keys/buttons. T-Square This tool has two toggle buttons in the top left: horizontal (x-axis) and vertical (y-axis). When either are on and the mouse is clicked and held, the cursor becomes locked to that axis, allowing the player to place blocks, walls, and wires in straight lines. Circle Compass Same as the T-Square, but the cursor becomes locked to the same distance from the player as when they clicked the mouse. This helps players place blocks in circles and arcs around a center point. Both of these tools would be great for the average user, and marvelous for people who live with shaky hands.