Added documentation for the Tones node

material_maker/doc/node_filter_tones.rst

@@ -0,0 +1,38 @@
+Tones node
+~~~~~~~~~~
+
+The **Tones** node provides an easy interface to adjust the tones of its input. It can be applied
+homogeneously to the R, G and B channels, or separately on R, G, B and A.
+
+The nodes shows an histogram of all channels of its input, and 3 cursors to modify the input
+adjustment at the top, and 2 cursors to modify the output adjustment.
+
+.. image:: images/node_filter_tones.png
+	:align: center
+
+Inputs
+++++++
+
+The **Tones** node requires an RGBA input texture.
+
+Outputs
++++++++
+
+The **Tones** node provides a single RGBA texture.
+
+Parameters
+++++++++++
+
+At the top of the node, a control can be used to select the active channel (Luminance, Red,
+Green, Blue and Alpha).
+
+The button can be used to adjust automatically the Tones to the node's input to obtain better
+contrast.
+
+The 3 cursors at the top of the histogram can be used to select the input colors that will be
+remapped to black (value = 0 for single channel), mid-grey (value = 0.5) and white (value = 1).
+Values between those defined by cursors are interpolated linearly, and all values are clamped
+between 0 and 1.
+
+The 2 bottom cursors define the output color for black (value = 0 for single channel) and
+white (value = 1). 

material_maker/doc/nodes_filter.rst

@@ -9,6 +9,7 @@ The filter nodes accept one or several inputs and generate one or several images
 	node_filter_invert
 	node_filter_brightness_contrast
 	node_filter_adjust_hsv
+	node_filter_tones
 	node_filter_greyscale
 	node_filter_colorize
 	node_filter_combine