Tactile Graphics Language
Welcome to the Official bTactile Manual, the tactile graphics language developed within the Biblos environment. This high-level programming tool is a landmark in the creation of accessible graphic content, enabling the design and generation of vector-based diagrams intended for tactile printing and use by blind and visually impaired individuals.
bTactile is an elegant and powerful language, designed to make tactile graphics an expressive and technical domain accessible to all. Thanks to its intuitive syntax and declarative logic, bTactile allows for the creation of precise, scalable, and reusable visual-tactile representations, suitable for educational, scientific, artistic, and communicative contexts.
Manual Objectives:
- Introduce the fundamentals of the bTactile language, illustrating its philosophy, structure, and intended use.
- Describe in detail the syntax, semantics, and main commands of the language.
- Guide users through the creation of effective tactile graphics via concrete and progressive examples.
- Promote digital inclusion by making graphic production accessible even to those who cannot rely on visual perception.
This manual is designed to be accessible both to those approaching programming for the first time and to users with technical experience who wish to explore the full potential of the language. Each concept is introduced progressively and supported by clear explanations, applied examples, and practical tips for effective and informed use.
This manual is intended for:
- Educators and practitioners involved in teaching blind or visually impaired students;
- Technicians and transcribers engaged in producing tactile materials;
- Experienced blind users seeking to explore new accessible programming languages;
- Developers and designers aiming to integrate inclusive graphic solutions into their projects.
bTactile stands as an outstanding achievement in the field of accessible graphics: a unique language that combines simplicity, precision, and expressive power. Its development is part of Biblos's mission to break down digital barriers and promote truly inclusive tools.
Both the language and this manual are in continuous development. Each update reflects user experience, collected feedback, and emerging needs in the field of tactile and accessible communication.
bTactile and this manual were designed and developed by Giuseppe Di Grande, who holds all copyright and publishing rights, in any form and by any means. Reproduction, even in part, is prohibited without the explicit permission of the author.
Table of Contents
- Introduction to the Language of Tactile Graphics
- The variables
- The numbers
- The arithmetic operators
- The constants
- Logical operators
- The procedures
- The functions
- Relational operators
- If conditional control
- The For cycle
- The While cycle
- All Instructions
- Abs- Returns the absolute value of a number
- Arc- Draws an arc
- ArcB- Draws an arc through three points
- ArcTan- Returns the arctangent of a number
- ArcTan2- Returns the angle between the X-axis and a segment of a line
- Braille- Draws a braille text
- BrailleHeight- Returns the height in points of the braille string
- BrailleType- Sets the characteristics of braille text
- BrailleWidth- Returns the width in points of the braille string
- Brush- Sets a brush type
- CharToNum- Converts the character into its Unicode code
- Chord- Draws a chord
- ChordB- Draw a chord through three points
- Circle- Draws a circle
- ColorBrush- Sets the brush color
- ColorPen- Sets the pen color
- Cos- Returns the cosine of an angle
- DegToRad- Converts angle from degrees to radians
- Dot- Draws or detects the color of a point
- Ellipse- Draws an ellipse
- Exp- Returns natural logarithm elevated to power
- Fill- Fills a surface
- Font- Sets a font type
- FontName- Sets the name of the current font
- FontSize- Sets the size of the current font
- FontStyle- Sets the style of the current font
- Frac- Returns the fractional portion of a number
- FrX- Returns the percentage fraction of the width of the graph
- FrY- Returns the percentage fraction of the height of the graph
- GraphicCrop- Crop the image to the chosen size
- GraphicOffset- Sets an offset to drawing coordinates
- GraphicOrigin- Sets the origin point of rotation
- GraphicRotate- Rotate entire graph
- GraphicScale- Changing the scale factors of the graph
- GraphicSize- Change the size and appearance of the graph
- GraphicTransparent- Changing the type of image transparency
- InsertPicture- Inserts an image into the graph
- Int- Returns the entire part of a number
- Line- Draws a line
- Ln- Returns the natural logarithm of a number
- Max- Returns the percentage fraction greater than the size of the graph
- Mid- Returns the average percentage fraction of the graph size
- Min- Returns the smallest percentage fraction of the graph size
- MsgBox- Shows a message box
- NumToChar- Converts the Unicode code into its character
- NumToString- Converts number to string
- OpenPicture- Opens an image
- Pen- Sets a pen type
- Polygon- Draws a polygon
- Polyline- Draws a series of lines
- PolyReg- Draws a regular polygon
- Pow- Returns number elevated to power
- RadToDeg- Converts angle from radians to degrees
- Random- Returns a random number
- Rectangle- Draws a rectangle
- Root- Returns the root of a number
- Round- Returns the rounded value of a number
- SavePicture- Save the picture
- Sin- Returns the sine of an angle
- Spline- Draw a quadratic curve of Bezier
- Square- Draws a square
- StringCopy- Returns a part of a string
- StringDelete- Deletes a part of a string and returns the remaining string
- StringLeft- Returns a substring from the left side of the string
- StringLength- Returns the length of a string
- StringLower- Returns the string with the letters in lower case
- StringRight- Returns a substring by taking it from the right side of the string
- StringToNum- Converts the string into a numerical value
- StringTrim- Returns the string without the initial and final spaces
- StringUpper- Returns the string with all letters in upper case
- Tan- Returns the tangent of an angle
- Text- Draws a text
- TextHeight- Returns the height in points of the string
- TextWidth- Returns the width of the string in points
- Triangle- Draws a triangle
- Trunc- Returns the truncated value of a number
- TurtlePos- Place and orient the turtle in the plane
- TurtleRight- Turn the turtle to the right
- TurtleLeft- Turn the turtle to the left
- TurtleForward- Makes the turtle walk forward
- TurtleBackward- Makes the turtle walk backwards
- VectorToDeg- From a vector returns the angle in degrees
- VectorToRad- From a vector returns the angle in radians