Conceptual
A common tool in short term planning and project management, Gantt charts are a type of bar chart designed to illustrate groups of tasks by start and end date. For more information on Gantt charts in general click here.
Grouping
Any Gantt chart groups tasks together. The grouping in Spry Gantt Charts is based on matching (captions and colours). If everything matches then tasks are grouped and as soon as something doesn’t match, a new group is formed. The example below shows the difference between a caption that is Pit/Stage and a caption that is Pit/Stage/Strip.
Hidden vs Filtered
You have two options to remove certain tasks from being seen, by hiding or filtering. The difference lies in the way they affect grouping. Filtering something will not affect the grouping, but will remove the related groups from view. Hiding something will allow it to be grouped with surrounding tasks. See the screenshot below for a basic example.
Colouring
There are 2 or 3 colours (depending on whether the process bar is shown or not). See the screenshot below for an example of how you can control the colours on each Gantt Chart.
Practical
Gantt Charts rely on an understanding of the Expression Editor.
When creating a Gantt Chart, you are provided with some default settings which should give you a platform to build upon.
Captions
Captions are similar to Filter Type Custom Fields, in that they return a Text String that groups lines of an Output Schedule together.
Levels (Sets Rows, Background Colour)
The default Level is Equipment, however you can change this and/or add a cascading structure. The Level/s also set the Background Colour.
Job Colour Level (Sets Group Colour)
Each group has a main colour which is set by the Job Colour Level.
Process Bar (On/Off)
The final colour/grouping option, switching the Process Bar on and off can effect your grouping as demonstrated in the screenshot below.
Timelines
You control the Timeline headers that are visible, as well as the vertical lines, through the Timelines tab in settings as well as by right-clicking the Time header on the Gantt Chart itself. Any Reporting Period that isn’t already present can be added as a timeline using the Add Timeline button 
Filters
As discussed in the Conceptual section, filters allow you to remove groups from view but not affect the grouping of surrounding tasks.
Equipment, Process and Levels Tabs
Control the colours and hidden tag of each through the various tabs.
Navigate to Schedule
A very useful diagnostic tool, if you have a Group you have identified as having an impact on your Schedule that you would like to see in the Animation, Navigate to Schedule will switch the Animation View to the earliest Start Date in the Group.
Major Updates
Version 1.5.0.811 introduces several improvements to Gantt Charts.
Results Tab
Allows you to present rows of results at the bottom of your Gantt Chart, split by Reporting Period, such as Operating Hours, Source Quantity, and Value Custom Fields.
NOTE: When using a Value Expression, make sure you use Schedule Result Functions (e.g ScheduleSum, ScheduleWeightAvg) as you are presenting an aggregated result. For example
ScheduleSum(OperatingHours)
Settings Tab
The Settings menu has several new fields and there are two new tabs. New features are outlined in red.
Split Tasks by Reporting Level
Allows you to split Grouped Tasks by a selecting a Reporting Period from the drop down menu and ticking the box next to the field.
Colour Selection Columns
Additional colour selection options have been provided in the Equipment, Processes and Levels tabs. A Bulk Edit button has been added to these tabs and is located on the far right of the screen.
The new colour options include: Text Colour, Header Colour, Header Text Colour and Appointment Border Colour.
The Header Text Colour and Appointment Border Colour columns will not appear if the Automatic Caption Colour and Automatic Appointment Border Colour options have been ticked on in the main Gantt Chart Settings tab.
Automatic Colouring Options
Ticking the Automatic Caption Colour option has the effect of automatically changing the colour of your Header Text. Based on the colour of your Caption, the text will change to White or Black for best readability.
Ticking the Automatic Appointment Border Colour option applies the same principles to the border of your groups.
Limit Rows Per Level
This option limits the number of Rows a given resource can take up. This is a middle ground between Clip Captions (1 row) and Clip Captions off (unlimited rows). The last row will be clipped.
Custom Fields Tab
Filter Custom Fields can now be selected in the ‘Levels’ and ‘Job Colour Level’ settings.
Once selected and applied to the Gantt Chart, go to the Custom Fields tab in the Settings menu. You can select from your Custom Fields and amend caption text and colours. The menu bar on the right lets you add, remove, reorder and sort your Identifiers. Identifiers represent potential Filter Custom Field results, their captions, and colours.
NOTE: Custom Field Identifiers are automatically populated when the field is selected as a Level in the main settings page, and ‘OK’ or ‘Apply’ has been clicked.
Schedule End Date Lock
Clicking the icon to the “Locked” position links the End Date to the Start Date. Moving the Start Date backwards or forwards will shift the End Date by an equal amount of time. The result is that the total time elapsed will not change.
Click the lock again to the “Unlocked” position so that any further changes to the Start Date will not affect the End Date.