+Note2: The operational result is based on the maximum transparency value of that background.
+
+\paragraph{Case 1, Positive Fade:} When the fade for all of the masks is positive, affecting the area inside of the mask, all of the
+background colors are at a transparency value of zero. So the largest transparency value is 0,and all masks are drawn with opaque backgrounds, depicted as one would expect.
+
+\paragraph{Case 2, Negative Fade:} When the program computes the background color for any number of masks that includes negative
+mask(s), it uses the largest transparency number as the determining factor for the background. Only 1 of the masks can be largest, and wins for the background transparency result.
+
+\vspace{3ex}\textit{Feather}: works in a similar manner to a \textit{gradient Fade} aligned on the mask boundary but is a logical function instead of a mathematical function so will be faster. The \textit{Gang feather} symbol also works in a similar fashion and is surrounded by a colored background when it is in effect.
+
+\subsubsection*{Mask Points section}%
+\label{ssub:masks_points_section}
+
+This section is used to change to a different mask number and manipulate the masks you have created.
+
+The \textit{Point}: textbox provides the ability to change which point number for the current mask that you want to work on. It has a tumbler to allow for quickly switching the point number. The \textit{X:} and \textit{Y:} boxes below reflect the current values and allow for modifying the $X/Y$ coordinates and these too have tumblers. The \textit{Delete} button will allow for deleting the selected point number.
+
+The next 6 symbols in 2 columns represent \textit{Smooth} and \textit{Linear} buttons. Smooth buttons use an algorithm based on the previous point and the next point to create a curved line. The smoothing operation takes three points, A, B, C, and arranges the slope at B to be AC as it moves to the next point for that mask.
+
+\textit{smooth point} $\rightarrow$ smooth a single point.
+
+\textit{smooth curve} $\rightarrow$ smooth all points on a mask edge curve.
+
+\textit{smooth all} $\rightarrow$ smooth all enabled masks on this track.
+
+Linear buttons of \textit{linear point}, \textit{linear curve}, and \textit{linear all}, perform the inverse of the smooth functions.
+The control point vectors on the bezier endpoints are set to zero magnitude.
+
+In addition there is a \textit{Markers} and a \textit{Boundary} checkbox which come in handy to turn off the display of the points and the outline of the mask. Turning off \textit{Markers} is very useful when you have a lot of control points that clutter the display and make it more difficult to see the actual mask. A helpful feature is available by disabling \textit{Markers} and enabling \textit{Boundary} which results in all masks being displayed in the viewer
+even if they are not enabled; for example you can then see mask 0, mask 1 \dots at the same time.
+
+A \textit{gang} symbol on the right hand side of this section, tooltip of \textit{Gang points}, is another useful feature that makes it easy to drag a mask to an exact coordinate using the \textit{X} or \textit{Y} textbox for numerical input or the associated tumblers. This works like the \texttt{Alt+LMB drag} translate but provides the ability to be precise.
+
+\subsubsection*{Pivot Point section}%
+\label{ssub:pivot_point_section}
+
+The \textit{X:} and \textit{Y:} coordinates mark the value of the current \textit{Pivot Point} used for rotation, scaling, and translation. You can either directly key in numerical values or use the tumblers to change the values as long as the \textit{Focus} checkbox is checked.
+
+The \textit{Focus} checkbox is used in case you want to set a different point in the Compositor for pivoting instead. And the \textit{Gang} symbol for rotate/scale/translate means that these operations will be performed on all points of the enabled masks. The gang symbol is surrounded by a colored background when it is in effect. When performing a rotate operation on a mask with the mouse wheel, \textit{acceleration} is in effect -- this means the faster you wheel, the more space is covered so that you do not have to wheel dozens of time to make a full rotation. Then when you wheel around slower, you can fine tune the result.
+Note that in order to be able to rotate/scale around pointer, the Focus checkbox must be unchecked.
+
+\subsubsection*{Other sections}%
+\label{ssub:other_sections}
+
+Finally there are the \textit{Apply masks before plugins} and \textit{Disable OpenGL masking} self-explanatory checkboxes.
+
+Note: Not all OpenGL software can support the current masking methods. If your opengl implementation does not support Shader Version 4.3 or has trouble with this (it is relatively new to opengl at the time this was implemented), then this checkbox will allow you to use the software masking to avoid any potential issues. Normally, OpenGL is probed for the shader version and will automatically use the software implementation if required.
+
+The \textit{Help} checkbox can be enabled in order to see a list of the keys used to perform various operations. If you use Masking infrequently, these are a valuable reminder to which key combinations to use. Currently they are as follows:
+
+\vspace{2ex}
+\begin{tabular}{ll}
+ \hline
+ Shift+LMB & move an end point \\
+ Ctrl+LMB & move a control point \\
+ Alt+LMB & to drag translate the mask \\
+ Shift+MMB & set Pivot Point at pointer \\
+ Wheel & rotate around Pivot Point \\
+ Shift+Wheel & scale around Pivot Point \\
+ Ctrl+Wheel & rotate/scale around pointer \\
+ \hline
+\end{tabular}
+
+\subsubsection*{Key Alternatives}%
+\label{ssub:key_alternatives}
+
+\vspace{2ex} Note: For some desktop window managers, certain keys may already be in use by the operating system, so you will either have to redefine them in your desktop or use different key combinations. For example, at least some desktops used with \textit{UbuntuStudio 16.04} and \textit{Arch} field the \texttt{Alt} key, thus requiring alternative key combinations to be needed. Below are some of these alternatives.
+
+\vspace{2ex}
+\begin{tabular}{lp{11cm}}
+ \hline
+ LMB & move/create an end point (to move the end point the pointer must be above the point) \\
+ Shift+LMB & move an end point (the pointer may be near the point, not above it) \\
+ Ctrl+LMB & move/create a control point \\
+ Alt+Ctrl+LMB & to drag translate the mask \\
+ Shift+Key Delete & to delete the mask \\
+ Shift+MMB & Set Pivot Point at pointer \\
+ Alt+Wheel & zoom in/out the screen (also available in Ubuntu16 but does not exist in all distros) \\
+ \hline
+\end{tabular}
+
+\vspace{2ex}
+Focus checkbox = unchecked: