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NY Signal drawn by 3rd PlanIt

NY Signal drawn 
3rd PlanIt by Walter Griffin

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A section of straight track, known also as "tangent track", is represented in 3rd PlanIt by a Line. Lines are used to represent track, simple lines, wood and walls. This allows fast design and modification of a wide range of materials, including their 3D rendering. In these examples, you'll see how lines are drawn in a variety of ways, then take on the look of track when drawing is complete.

In these examples, 3rd PlanIt's Color by Object Type mode has been used to highlight the lines, curves and spiral easements created by drawing. This important feature makes editing broad curves and easements predictable regardless of viewing magnification.

Drawing Lines

Lines may be drawn Freehand, starting from any location and moving to another. If you hold down the Shift key while drawing, the line is constrained to horizontal or vertical. Holding the Alt key when you begin a line indicates you want to draw from the endpoint of an existing object. The Draw Perpendicular tool can be used to draw a line perpendicular to any object. Click for animation (271K)

Using the Draw Tangent you can interactively draw a line tangent to an existing curve. If you click the right mouse button while drawing the line, the line swaps sides of the circle. You can Double-Click any object to adjust its endpoints. Click for animation (220K)

You can draw a line as a projection from an existing curve, spiral or line with the Draw Projecting Line tool. The projecting line will be exactly tangent to the existing object at its endpoint. You can adjust the line length by moving the mouse. Click for animation (74K)

The Draw Line and Curve tool projects a line from an existing curve with a Transition Curve to smoothly change the radius to tangent. As you extend the line, the easement extends to its maximum length. By hold the Shift key down, you can hold the easement to a desired length. Click for animation (104K)

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Last modified: October 16, 2018