Profiles can have arbitrary (nonempty) number of handles, with any available transformations, including non-interactive (for example, coordinate axes). Filtering of the handles in the current profile can be done by using filters by type of transformation from the selector settings dialog.

Filtering handles of the current profile by type of transformation
User can create his own profiles or modify existing ones. There are, however, certain specific characteristics of profile loading that need to be observed. To save time on reading the TCW file, profiles are unloaded only when the application is closed. Otherwise they would have to be opened/closed upon each activation of the corresponding dragger (for example, selector). This would have slowed down the work significantly. So if a profile is already uploaded to memory, reloading it (for instance, after editing) is possible only after restarting the application. New profile can be set up without application restart.
When we give user the ability to develop profiles, it is desirable to also provide a set of development tools. For example, 'Reload profile' button and the ability to create current profile report, which would show the number of handles, loading errors, etc. I hope this will be added in future.

Samples

Samples folder contains several examples of different profiles. It makes sense to start all new templates from template.tcw, which contains the minimum set of handles and also includes all required variables (graphic`s custom properties).

Template.TCW profile

Defined custom properties.
MoveRotate2D.TCW sample demonstrates the possibility to create selector in "protractor" style. It contains 12 handles for movement along axis, positioned at every 30 degrees, and a handle for rotating around the Z axis.

MoveRotate2D.TCW profile
FlatGrid3x3.TCW example demonstrates the possibility to create a flat 5x5 grid from handles for accurate movement in the XY plane (reference point). Grid spacing is 1 in. A specific feature of this grid is that the distance between handles (1 in) does not change when zooming in/out. Ability to set fixed values of coordinates (in selector coordinate system) allows placing selector handles in critical points for drawing objects (for example, focal plane of the lens or focuses of an ellipse).

FlatGrid3x3.TCW profile

FlatGrid3x3.TCW profile, shown dynamically. Animated GIF (Animation only in HTML version)

Layers

All profiles that are distributed with TurboCAD have a certain system of layers. Each handle has its layer. This provides a way to hide unnecessary handles.
Layers whose names have the "handle_") prefix are used for handles. For example, "handle_MoveX" layer contains the handle for movement along the X axis.
Layers whose names have the " part_") prefix are used for parts of handles. For example, "part_MouseIn" layer contains geometry that becomes visible when the cursor hovers over the handle.

Fragment of layer table from a profile.
It should be noted that this system of layers exists only as an added convenience for profile development. When a profile is uploaded into the application, layer 0 is assigned to all handles.

Handles

When a profile is uploaded into the application, the loader analyzes graphics and uses certain criteria to identify handles. A handle is a 'group' graphic that has a certain set of subgroups and a set of custom properties. Graphics that do not meet these criteria are ignored.
A handle has to have several mandatory custom properties (of text type) that define its name, position, transformation type, etc. In addition to mandatory custom properties, there are optional properties. These properties are used by the program to determine the purpose, behavior, appearance of the handle, and its response to mouse movement. User can set other admissible values and change handle behavior that way.

Set of variables for Boundary Box handle.

Set of variables for MoveX handle.
The set of variables is not final, it can be changed and expanded.
A handle has to include a certain set of subgroups. Each of the subgroups is responsible either for drawing of for the behavior of the handle. Type of the subgroup is set by the handle_part variable:

'handle_part variable'
This variable can have one of the following values:
mouseout - visible geometry when the cursor is outside the handle
mouseover - visible geometry when the cursor is over the handle
active - visible geometry while dragging (optional)
static- visible geometry (optional)
coordsystem - invisible geometry, defining the coordinate system of the handle
highlight_area - invisible geometry, turns on mouseover, when the cursor is over it. If this part is absent, mouseout (optional) is used instead.
visibility_area - reserved (optional)

Parts of MoveX handle