Overview of the API

Note: The Lua version that comes with OS 3.x is 5.1.4, without the io nor os libraries.

Tutorials on Nspire Lua scripting in general are available here : http://inspired-lua.org/

Standard Library

( This has been taken from a WoWWiki page - See the full, official documentation here )

Common Lua Functions

• G - Global Variable - A global variable (not a function) that holds the global environment (that is, _G._G = _G). Lua itself does not use this variable; changing its value does not affect any environment, nor vice-versa. (Use setfenv to change environments.) - taken from Lua docs
• assert(value[, errormsg]) - asserts a value evaluates to true. If it is, returns value, otherwise causes a Lua error to be thrown.
• collectgarbage - among other things, force free unused memory.
• error(str) - generates an error with the str message.
• getfenv(function or integer) - Returns the table representing the stack frame of the given function or stack level.
• getmetatable(obj, mtable) - Returns the metatable of the given table or userdata object.
• next(table, index) - Returns the next key, value pair of the table, allowing you to walk over the table.
• newproxy(boolean or proxy) - Creates a userdata with a sharable metatable.
• print(...) - Receives any number of arguments, and prints their values. Not intended for formatted output, but only as a quick way to show a value, typically for debugging. For formatted output, use string.format.
• select(index, list) - Returns the number of items in list or the value of the item in list at index.
• setfenv(function or integer, table) - Sets the table representing the stack frame of the given function or stack level.
• setmetatable(obj, mtable) - Sets the metatable of the given table or userdata object.
• tostring - tostring (e) - Receives an argument of any type and converts it to a string in a reasonable format. For complete control of how numbers are converted, use string.format. If the metatable of e has a "__tostring" field, then tostring calls the corresponding value with e as argument, and uses the result of the call as its result. - taken from Lua Docs.
• tonumber - tonumber (e) - Receives an argument of the string type and converts it to a number when possible. If the metatable of e has a "__tonumber" field, then tonumber calls the corresponding value with e as argument, and uses the result of the call as its result. - taken from Lua Docs.
• type(var) - Returns the type of variable as a string, "number", "string", "table", "function" or "userdata".
• unpack(table[, start][, end]) - Returns the contents of its argument as separate values.
• xpcall(func, err) - Returns a boolean indicating successful execution of func and calls err on failure, additionally returning func's or err's results.

Coroutines Library

The coroutines are useful tools to control the running of differents parts of a code ("threads").

create, wrap, resume, yield, status, running

More information can be fouded in the coroutines page.

String Library

byte, char, dump, find, format, gmatch, gsub, len, lower, match, rep, reverse, sub, upper

Math Library

abs, acos, asin, atan, atan2, ceil, cos, cosh, deg, exp, floor, fmod, frexp, huge, ldexp, log, log10, max, min, modf, pi, pow, rad, random, randomseed, sin, sinh, sqrt, tan, tanh More information about the other libraries can be found on the Extended Standard Library Page

D2Editor

The Lua 2D editor bindings enable 2D rich text editors to be created and manipulated within scripts.

• D2Editor:createChemBox() : Inserts a Chem Box in the current cursor position of the editor.
• D2Editor:createMathBox() : Inserts a Math Box (Expression Box) in the current cursor position of the editor.
• D2Editor:getExpression() : Returns the contents of the text editor as a UTF-8 encoded string.
• D2Editor:getExpressionSelection() : Returns three values: the contents of the text editor (UTF-8 encoded string), the cursor position, and the selection start.
• D2Editor:getText() : same as getExpression : Returns the contents of the text editor as a UTF-8 encoded string.
• D2Editor:hasFocus() : Returns true if the editor has focus; otherwise returns false.
• D2Editor:isVisible() : Returns true if the editor is visible; otherwise returns false.
• D2Editor:move() : Sets the parent-relative location of the upper left corner of the text editor. Both x and y must be between -32767 and 32767.
• D2Editor:newRichText() : Creates and returns a new 2D rich text editor.
• D2Editor:registerFilter(handlerTable) : This routine registers a table of handler functions that can alter events before they are sent to the 2D editor widget, or unregisters if nil is passed.
• D2Editor:resize(w, h) : Changes the width and height of the text editor. Both width and height must be > 0 and < 32768.
• D2Editor:setBorder(thickness) : Sets the editor's border thickness. The thickness value must be between 0 and 10.
• D2Editor:setBorderColor(color) : Sets the editor's border color. The color value must be between 0 and 16777215 (0x000000 and 0xFFFFFF).
• D2Editor:setColorable(true or false) : Makes the expression colorable or uncolorable.
• D2Editor:setDisable2DinRT(true or false) : Turns on/off 2D layout of math input to the text box.
• D2Editor:setExpression(...) : Sets the text content of the text editor.
• D2Editor:setFocus(true or false) : Sets the user input focus on the editor if true (the default). This is usually called from the on.getFocus event handler.
• D2Editor:setFontSize(size) : Sets the text font size in the editor. Only 7, 9, 10, 11, 12, or 24 for the handheld, any on the desktop software.
• D2Editor:setMainFont(family, style) : Sets the main font family ("serif" or "sansserif") and style ("r", "b", "i", "bi").
• D2Editor:setReadOnly(true or false) : Makes the text editor content modifiable (false) or unmodifiable (true) by the user. If a Boolean value is not specified, defaults to true.
• D2Editor:setSelectable(true or false) : Makes the text editor content selectable (true) or unselectable (false) by the user. If a Boolean value is not specified, defaults to true.
• D2Editor:setSizeChangeListener(function(editor, w, h)) : Sets the callback function for when the editor contents exceed the current editor size, when the contents fit on fewer lines, or when the contents fit on a single line of smaller width.
• D2Editor:setTextChangeListener(function(editor)) : Sets the callback function for when the text expression changes, which will be to the editor object. This allows for processing text input as it occurs.
• D2Editor:setText(...) : Same as setExpression : Sets the text content of the text editor.
• D2Editor:setTextColor(color) : Sets the editor text color. The color value must be between 0 and 16777215 (0x000000 and 0xFFFFFF).
• D2Editor:setVisible(true or false) : Sets the visibility of the text editor.
• D2Editor:setWordWrapWidth(width) : Sets the rich text editor word-wrapping width in pixels. Ignored if the editor is in 2D mode. To indicate widget width, sets to 0. To disable wrapping, sets to < 0. The width must be -32767 to 32767.

Events

Events are one of the most fundamental things to know about the Nspire Lua language. You can see how events are managed inside the Lua implementation here.

• on.paint(gc) is called when the GUI is painted. 'gc' is the Graphics Context
• on.resize is called when the window is rezised
• on.timer is called at each timer ticks. See timer.
  
• on.arrowKey is called when an arrow key from the clickPad/TouchPad is pressed (right, left, up, down)
• on.arrowLeft is called when the left arrow is pressed
• on.arrowRight is called when the right arrow is pressed
• on.arrowUp is called when the up arrow is pressed
• on.arrowDown is called when the down arrow is pressed
• on.enterKey is called when the enter key is pressed.
• on.escapeKey is called when the escape key is pressed.
• on.tabKey is called when the tab key is pressed.
• on.deleteKey is called when the delete key is pressed.
• on.backspaceKey is called when the clear key is pressed.
• on.returnKey is called when the return key is pressed.
• on.contextMenu is called when the combo-key Ctrl Menu is pressed.
• on.backtabKey is called when the combo-key Maj Tab is pressed.
• on.clearKey is called when the combo-key Ctrl Clear is pressed.
• on.help is called when the combo-key Ctrl ? is pressed.
• on.charIn is called when the Nspire detects a non arrow key being pressed.
• on.createMathBox called when there is a MathBox created.
• on.create called when the script gets created. Deprecated in 3.2. See on.contruction.
• on.construction called when the script gets created.
• on.deactivate called when the focus is lost on the page (like launching the document, changing page etc...)
• on.activate called when the focus is on the page (like launching the document, changing page etc...)
• on.destroy is called when the document is about to get closed (or cut)
• on.getFocus is called when the script receives user input focus.
• on.loseFocus is called when the script loses user input focus.
• on.mouseDown is called when we press the left mouse button. X and Y are the pressed point coordinates.
• on.mouseUp is called when we release the left mouse button.
• on.mouseMove is called when the mouse moves
• on.grabDown is called when the grabbing motion is detected
• on.grabUp is called after the grabbing action.
• on.rightMouseDown is called when the user pushes the "right click" button
• on.rightMouseUp is called when the user releases the "right click" button
• on.keyboardUp() which fires when the tablet's on-screen keyboard gets shown.
• on.keyboardDown() which fires when the tablet's on-screen keyboard gets hidden.
• on.varChange is called when a monitored variable gets changed.
• on.getSymbolList is called when the script app symbol list is being serialized to the clipboard.
• on.save is called when the script app is saved to the document or copied to the clipboard.
• on.restore is called when the script application is restored from its saved state in a document or when the app is pasted into a document..
• on.cut is called when the user cuts something.
• on.copy is called when the user copies something.
• on.paste is called when the user pastes something.

Graphics Operations

gc is the Nspire's graphic context. A graphics context is a module that has a handle to the script’s graphics output window and a library of graphics routines that are used to draw on the window. A graphics context is supplied to the script ”on.paint” event handler each time the window needs to be redrawn. The graphics context employs a pixel-based coordinate system with the origin in the upper left corner of the drawing window.

• gc:clipRect(op, x, y, width, height) - Sets the clipping rectangle for subsequent graphics operations.
• gc:drawArc(x, y, width, height, start angle, finish angle).
• gc:drawImage(image,x,y) First argument in format “TI.Image”, x and y the coords.
• gc:drawLine(xstart, ystart, xend, yend) Draws a line starting at the point (xstart,ystart) and ending at the point (xend, yend)
• gc:drawPolyLine(int list1 [,int list2, .., int listN]) Draws a shape from a list contaning successively the x and y coordinates of each point the line have to draw.
• gc:drawRect(x, y, xwidth, yheight) Draws a rectangle at (x,y) with the “x” side being “xwidth” long and the “y” side being “yheight” long
• gc:drawString(string, x, y, position) position is the string’s anchor point and can be "baseline", “bottom”, “middle”, or “top”.
• gc:fillArc(x, y, width, height, start angle, finish angle) see gc:drawArc
• gc:fillPolygon(int list1 [,int list2, .., int listN]) see gc:drawPolyLine
• gc:fillRect(x, y, width, height) see gc:drawRect
• gc:getStringHeight(string) - Returns the string's height.
• gc:getStringWidth(string) - Returns the string's width
• gc:setAlpha(alpha) - where alpha is an integer between 0 and 255. Sets the transparency. Not available anymore in 3.2+
• gc:setColorRGB(red, green, blue) RGB values are integers, from 0 to 255.
• gc:setFont(font, type, size), with font : {“sansserif”, "serif", ..}, type {“b”, “r”, “i”}, size(int)
• gc:setPen(thickness, smoothness) : thickness {“thin”, “medium”, "thick"}, smoothness {“smooth”, "dotted", "dashed"}

Images

• image.copy(theImage, width, height) : Returns a copy of the input image scaled to fit the specified pixel width and height.
• image.height(theImage) : Returns the height of the image
• image.new(theImage) : Allocates a new TI.Image
• image.rotate(theImage, angle) : Returns a rotated copy of theImage by angle degrees
• image.width(theImage) : Returns the width of the image

Physics Engine

A port of Chipmunk Physics 5.3 has been embedded as an optional module (you have to 'require' it at the beginning of your script, in order to use it)

• Arbiters and Collision Pairs
• Bodies
• Bounding Boxes
• Circle Shapes
• Constraints
• Misc
• Polygon Shapes
• Segment Shapes
• SegmentQueryInfo
• Shape Queries
• Shapes
• Space Queries
• Spaces
• Vectors

Platform

• platform.isColorDisplay() : Returns true if the display of the host platform is color-capable (Nspire CX and emulator). Returns false if the display is grayscale (Nspire non-CX).
• platform.isDeviceModeRendering() : Returns true if the script is running on the hand-held device or in the emulator (with the calculator view), and false if the script is running in the normal view of the emulator.
• platform.isTabletModeRendering() : Returns true if the script is running on a tablet device (iPad app) and false otherwise.
• platform.window : Returns the window object currently owned by the script application. The window object contains several other methods.
• platform.withGC(...) : executes a function which a passed dummy gc.
• platform.registerErrorHandler(...) : A global error handler for the lua script.
• platform.hw() : returns a number corresponding to the type of device the script is running on.

Timer

• timer.start(period) : Starts the timer with the given period (in seconds)
  
• timer.getMilliSecCounter() : Returns the value of the milliseconds elapsed since the calculator's last boot.
  
• timer.stop() : Stops the timer.

Toolpalette

The tool palette provides a menu of commands, selectable by the user, that invoke functionality of the script app. The menu itself is accessible by pressing the "Menu" button.

• register(menuStructure) : Registers the menuStructure table.
• enable(toolname, itemname, state) : Enables or disables a menu item in the tool palette.
• enableCopy(state) : This routine enables / disables the Edit > Copy menu command.
• enableCut(state) : This routine enables / disables the Edit > Cut menu command.
• enablePaste(state) : This routine enables / disables the Edit > Paste menu command.

var

'var' functions allows the script to interact with BASIC variables.

• var.list() - Lists of names of variables currently used.
• var.monitor(name) - Turns on monitoring of the math variable with given name.
• var.unmonitor(name) - Turns off monitoring of the math variable with given name.
• var.makeNumericList(name) : Creates a list in the symbol table with the given name, which is optimized to hold numeric values.
• var.recall(name) : Returns the value of a math variable with the given name.
• var.recallAt(name, col [,row]) : Recalls a value from a cell of a list or matrix in the symbol table.
• var.recallstr(name) : Returns the value of a math variable with the given name as a string.
• var.store(name, value) : Stores value as a math variable with the given name.
• var.storeAt(name, numericValue, col [,row]) : Stores a numeric value into an element of a math list or matrix with the given name.

Misc.

• locale.name() : Returns the name of the current locale as an ISO-639 code.
• clipboard.addText(string) : Add 'string' to the clipboard
• clipboard.getText() : Get the current content of the clipboard
• cursor.hide() : Hides the cursor on the screen
• cursor.set(cursorname) : Sets the new shape of the cursor to cursorname (see full list in the specific article)
• cursor.show() : Makes the cursor visible on the screen
• document.markChanged() : Mark the current document as changed