Adjusts map values using a user-defined curve. It works similar to the curves adjustment in graphics editors like Photoshop. The horizontal axis of the curve chart is the input value, vertical axis is the output value.
This generator provides plenty of opportunities for map editing: it can be used to invert maps, adjust minimum or maximum values, clamp map values or even make ladder slopes (although a terrace generator could be more handy for this).
For example, to give the map more contrast just move left and right keys horizontally closer to the central line. To invert the map move the left key to the top and the right key to the bottom so that the diagonal line is inverted (note that key tangents should be set to auto to achieve a straight line).
Imagine you have a mountain with more or less straight slope going from the zero level up to it's top at the level one - this slope will be the default linear curve. When we add a point and drag it down we change the shape of this imaginary slope, and all of the other slopes as well.
Curve field: displays a curve preview. To create a point click anywhere at the curve. To move the point - drag it with the mouse. You can create a point and start dragging, just keep the mouse button pressed. To delete the point drag away anywhere from the curve field. The first and the last points are draggable too.
If any of the terrain tiles assigned as preview - the curve field background shows preview tile histogram. Note that the histogram does not represent a terrain tile relief, slice or part of it, it's completely different thing.