The environment of tactile graphics
The tactile graphics environment is used to draw and construct graphics for printing with the Braille printer. The touch graphic window has the following elements.
- The menu bar with all the commands;
- the side toolbar with some commands for immediate use;
- the writing area into which the vector instructions are typed;
- the picture with the image of the tactile graph you are drawing;
- the status bar with some information.
The tactile graph is drawn using vector instructions, with which all users, both visually and visually impaired, can draw their own graphs. All instructions can be typed manually, guided input windows (Insert menu) can be used, or they can be drawn with the mouse directly in the graphics pane.
In the vectorial code sheet you can move freely, being a normal multiline editing field. So you can type, copy, paste, edit, delete.
On the left side of the window there is a large graphic box, which shows the tactile graph. When you type instructions manually, the graph does not update automatically, but you must use the Render command. During the rendering phase, any syntax errors are reported in the status bar. Using guided insertion commands, rendering is automatic.
Rendering also updates the status bar, especially the Density and Fragmentation values, which are useful for understanding the structure of the tactile graph. In addition, in the case of an incorrect code, the type of error that blocked the rendering is described.
The graphic frame can be used to draw basic vectorial figures with the mouse. In order to draw a geometric figure, it is essential to choose the type of figure you want to draw. Therefore, click the right mouse button, making sure that the pointer is inside the graphics area, and choose the desired figure.
During direct drawing, the information in the status bar shows the coordinates of the mouse inside the touch area, the rotation of the figure and the zoom. It also shows which geometrical figure is activated for the drawing.
The vector points are always fixed using the left button. During drawing, the right button is used to cancel the last vectorial point. The vector points to be fixed for each figure depend on the geometric figure you are drawing. For example, if you draw a point, the left button on the first click fixes and draws the touch point. For the Line there are two vectorial points to be fixed.
For figures whose vectorial points are variable - Polygon and Regular Polygon - the last point of the figure is always fixed by left-clicking while holding down the Ctrl key.
When drawing, the mouse wheel is used to rotate the geometric figure around its center. If you hold down the Ctrl key the wheel is used to enlarge or reduce the figure always with reference to its center.
When you fix the last point of a figure, the instruction for the figure is automatically inserted into the touch graph.
The tactile graph generally uses two colours: black to indicate tactile points, and white to indicate blank surfaces. In general, dark colours produce tactile points, while light ones are empty surfaces.
The status bar contains useful information about the tactile graph. The first information refers to the position of the cursor in the writing area. These values change as you move or write code. Two very important values follow: Density and Fragmentation. Shows the percentage of dot composition in the tactile graph.
The Density value indicates the percentage of full (or raised) points that the graph contains. A low density indicates a bare-touch tactile graph of dots. If the density is too high, the graph is full of dots.
The Fragmentation value instead indicates the uniformity of points that the graph has. Low fragmentation indicates a uniform and compact graph, whether full or dotted. A too high fragmentation is an indicator of graphs with too much jagged and discontinuous dots.
The last information in the bar indicates the status of the code. After rendering, if the code has errors, the line number and the type of error found are displayed.
The menu bar contains commands for the management of tactile graphs. Some commands are also contained in the toolbar on the right side of the window. The commands on the toolbar are identical to those in the menus, so the use of one or the other leads to the same results.
There are three main menus: "File", "Insert" and "Tools":
- The File menu contains commands for opening, saving and printing graphs;
- The Insert menu contains guided entry commands for vector instructions;
- The Tools menu contains commands for rendering graphs and general settings.