# Usage
## Command line
Usage: DOjS.EXE [-r] [-s] [-f] [-a] <script>
    -r             : Do not invoke the editor, just run the script.
    -w <width>     : Screen width: 320 or 640, Default: 640.
    -b <bpp>       : Bit per pixel:8, 16, 24, 32. Default: 32.
    -s             : No wave sound.
    -f             : No FM sound.
    -a             : Disable alpha (speeds up rendering).

## Editor keys
    F1  : Open/Close help
    F3  : Save script
    F4  : Run script
    F7  : Find text
    F9  : Show/Close logfile
    F10 : Quit

    Shift-F4       : Truncate logfile and run script
    Shift-F7       : Find again
    CTRL-D         : Delete current line
    SHIFT+Movement : Select text, releasing SHIFT deselects
    CTRL-C         : Copy selection
    CTRL-X         : Cut selection
    CTRL-V         : Paste
    CTRL-LEFT      : Previous word
    CTRL-RIGHT     : Next word
    PAGE-UP        : One page up.
    PAGE-DOWN      : One page down.
    HOME           : Go to start of line
    END            : Go to end of line
    CTRL-HOME      : Go to start of line
    CTRL-END       : Go to end of line
    TAB            : Insert spaces until next TAB-stop at cursor
    SHIFT-TAB      : Reduce indentation of line.

    TAB size is 4.
    The help viewer will remember the current position.

    The logfile can be truncated by pressing DEL in the log viewer.

# JS API description
A very minimal API documentation.

## Script format
Scripts need to provide three functions: `Setup()`, `Loop()` and `Input()`. Scripts are loaded and executed top-own. After that `Setup()` is called once and then `Loop()` repeatedly. `Input()` is called whenever mouse of keyboard input happens.

### Setup()
This function is called once at startup. It can initialize variables, setup hardware, etc.

### Loop()
This function is called after setup repeatedly until `Stop()` is called. After calling `Stop()` the program ends when `Loop()` exits.

### Input(event: {x:number, y:number, flags:number, buttons:number, key:number, kbstat:number, dtime:number})
This function is called whenever mouse/keyboard input happens. The parameter is an event object with the following fields: `{x:number, y:number, flags:number, buttons:number, key:number, kbstat:number, dtime:number}`. The definitions for the `flags` and `key` field can be found in `jsboot/func.js`.

## File
### f = new File(filename:string, mode:string)
Open a file, for file modes see `jsboot/file.js`. Files can only either be read or written, never both. Writing to a closed file throws an exception.

### f.ReadByte():number
### f.ReadLine():string
Read a single byte/line from file. The maximum line length is 4096 byte.

### f.WriteByte(ch:number)
### f.WriteString(txt:string)
### f.WriteLine(txt:string)
Write a byte/string/NEWLINE terminated string to a file.

### f.Close()
Close the file.

## Color
See `jsboot/color.js` for predefined EGA colors. Use `NO_COLOR` for the transparent color.

### Color(red:number, green:number, blue:number[, alpha:number]):number
Create a RGBA color.

### GetRed(c:number):number
### GetGreen(c:number):number
### GetBlue(c:number):number
### GetAlpha(c:number):number
get the R/G/B/A part of a color.

## Bitmap
### bm = new Bitmap(filename:string)
Load a BMP or PNG image.

### bm = new Bitmap(width:number, height:number)
Create Bitmap of given size.

### bm.filename
Name of the file.

### bm.width
Width in pixels

### bm.height
Height in pixels

### bm.Draw(x:number, y:number)
Draw the image to the canvas at given coordinates.

### bm.DrawTrans(x:number, y:number)
Draw the image to the canvas at given coordinates using RGBA transparency.

### bm.GetPixel(x:number, y:number):Color
get the color of an image pixel.

## Font
See `jsboot/font.js` for direction and alignment values.

### f = new Font(filename:string)
Load a .FNT file for GRX.

### f.filename
Name of the file.

### f.height
Font height.

### f.DrawStringLeft(x:number, y:number, text:string, foreground:Color, background: Color)
### f.DrawStringCenter(x:number, y:number, text:string, foreground:Color, background: Color)
### f.DrawStringRight(x:number, y:number, text:string, foreground:Color, background: Color)
Draw a string to the canvas.

### f.StringWidth(text:string):number
Calculate string width for this font.

### f.StringHeight(text:string):number
Calculate string height for this font.

## Midi
### mid = new Midi(filename:string)
Load a midi file.

### mid.Play()
Play the midi file.

### mid.filename
Name of the file.

### mid.length
Get file playtime.

### MidiIsPlaying():boolean
Check if the file is still playing

### MidiPause()
### MidiResume()
### MidiStop()
Pause/resume/stop playing midi.

### MidiGetTime():number
Get current play position.

### MidiOut(data:number[])
Send MIDI commands to output.

## Sample
### snd = new Sample(filename:string)
Load a WAV-file.

### snd.filename
Name of the file.

### snd.length
Sound length.

### snd.frequency
Sound frequency.

### snd.Play(volume:number, panning:number, loop:boolean)
Play the WAV.

### snd.Stop()
Stop the sound.

## Drawing functions

### SetRenderBitmap(bm:Bitmap)
Set the current render destination. Empty or null for screen bitmap.

### SizeX():number
get the width of the drawing area.

### SizeY():number
get the height of the drawing area.

### ClearScreen(c:Color)
clear the screen with given color.

### Plot(x:number, y:number, c:Color)
draw a point.

### Line(x1:number, y1:number, x2:number, y2:number, c:Color)
draw a line.

### Box(x1:number, y1:number, x2:number, y2:number, c:Color)
draw a box.

### Circle(x1:number, y1:number, r:number, c:Color)
draw a circle.

### Ellipse(xc:number, yc:number, xa:number, ya:number, c:Color)
draw an ellipse.

### CircleArc(x:number, y:number, r:number, start:number, end:number, style:number, c:Color):{"centerX":XXX,"centerY":XXX,"endX":XXX,"endY":XXX,"startX":XXX,"startY":XXX}
Draw a circle arc. Returns an object with coordinates of the drawn arc: `{"centerX":XXX,"centerY":XXX,"endX":XXX,"endY":XXX,"startX":XXX,"startY":XXX}`.

### CustomLine(x1:number, y1:number, x2:number, y2:number, w:number, c:Color)
draw a line with given width.

### CustomCircle(x1:number, y1:number, r:number, w:number, c:Color)
draw a circle with given width.

### CustomEllipse(xc:number, yc:number, xa:number, ya:number, w:number, c:Color)
draw an ellipse with given width.

### CustomCircleArc(x:number, y:number, r:number, start:number, end:number, style:number, w:number, c:Color):{"centerX":XXX,"centerY":XXX,"endX":XXX,"endY":XXX,"startX":XXX,"startY":XXX}
Draw a circle arc with given width. Returns an object with coordinates of the drawn arc: `{"centerX":XXX,"centerY":XXX,"endX":XXX,"endY":XXX,"startX":XXX,"startY":XXX}`.

### FilledBox(x1:number, y1:number, x2:number, y2:number, c:Color)
draw a filled box.

### FilledCircle(x1:number, y1:number, r:number, c:Color)
draw a filled circle.

### FilledEllipse(xc:number, yc:number, xa:number, ya:number, c:Color)
draw an ellipse.

### FilledPolygon([[x1, x2], [..], [xN, yN]], c:Color)
draw a filled polygon.

### FloodFill(x:number, y:number, border:Color, c:Color)
do a flood fill.

### GetPixel(x:number, y:number):Color
get color of on-screen pixel.

### TextXY(x:number, y:number, text:string, fg:Color, bg:Color)
Draw a text with the default font.

### TransparencyEnabled(b:boolean)
Enable/disable transparency.

### SaveBmpImage(fname:string)
Save current screen to file.

### SavePcxImage(fname:string)
Save current screen to file.

### SaveTgaImage(fname:string)
Save current screen to file.

## Keyboard/Mouse Input
### MouseSetSpeed(spmul:number, spdiv:number)
set mouse speed

### MouseSetLimits(x1:number, y1:number, x2:number, y2:number)
set mouse limits

## MouseSetCursorMode(mode:int, ...)
change mode of the cursor.

### MouseShowCursor(b:boolean)
show hide mouse cursor

### MouseWarp(x:number, y:number)
move mouse cursor

## Other functions/properties
### SOUND_AVAILABLE: boolean
`true` if WAV sound is available.

### MOUSE_AVAILABLE: boolean
`true` if mouse is available.

### IPX_AVAILABLE: boolean
`true` if networking is available.

### global: object
The global context.

### Print(a, ...)
Write data to `JSLOG.TXT` logfile.

### Println(a, ...)
Write data to `JSLOG.TXT` logfile.

### Stop()
DOjS will exit after the current call to `Loop()`.

### Sleep(ms:number)
Sleep for the given number of ms.

### MsecTime():number
Get ms timestamp.

### Read(filename:string):string
Load the contents of a file into a string.

### List(dname:string):[f1:string, f1:string, ...]
Get directory listing.

### Stat(name:string):{"atime":string,"blksize":number,"ctime":string,"drive":string,"is_blockdev":bool,"is_chardev":bool,"is_directory":bool,"is_regular":bool,"mtime":string,"nlink":number,"size":number}
Get information about a file/directory.

### MemoryInfo():{"used":XXX, "available":XXX}
Get memory statistics.

### Gc(info:boolean)
Run garbage collector, print statistics to logfile if `info==true`.

### SetFramerate(rate:number)
Set maximum frame rate. If `Loop()` takes longer than `1/rate` seconds then the framerate will not be reached.

### GetFramerate():number
Current frame rate.

### SetExitKey(key:number)
Change the exit key from ESCAPE to any other keycode from `jsboot/func.js`.

### CharCode(c:string)
Can be used to obtain the key code for `SetExitKey()` for a character, e.g. `SetExitKey(CharCode('q'))`.

### Require(filename:string):module
Used to load a module. The functions exported from this module can be accessed using the returned value.

### Include(filename:string)
Used to load a module. The functions exported from this module will be put into the global context.

## IPX networking
DOjS supports IPX networking. Node addresses are arrays of 6 numbers between 0-255. Default socket number and broadcast address definitions can be found in `jsboot/ipx.js`.

### IpxSocketOpen(num:number)
Open an IPX socket.

### IpxSocketClose()
Close IPX socket (if any).

### IpxSend(data:string, dest:array[6:number])
Send packet via IPX. Max length 79 byte.

### IpxCheckPacket():boolean
Check for packet in receive buffer.

### IpxGetPacket():{data:string, source:array[6:number]}
Get packet from receive buffer (or NULL).

### IpxGetLocalAddress():array[6:number]
Get the local address.

## 3D rendering
Please see the HTML help for details.

### CreateScene(nedge:number, npoly:number)
Allocates memory for a scene.

### ScenePolygon3D(type:POLYTYPE, texture:Bitmap, v:V3D[])
Puts a polygon in the rendering list.

### RenderScene()
Renders all the specified ScenePolygon3D()'s on the current bitmap.

### ClearScene()
Initializes a scene.

### DestroyScene()
Deallocate memory previously allocated by CreateScene.

### SetSceneGap(gap:number)
Set scene gap.

### Polygon3D(type:POLYTYPE, texture:Bitmap, v:V3D[])
Draw 3d polygons using the specified rendering mode.

### Triangle3D(type:POLYTYPE, texture:Bitmap, v1:V3D, v2:V3D, v3:V3D)
Draw 3d triangles, using vertices.

### Quad3D(type:POLYTYPE, texture:Bitmap, v1:V3D, v2:V3D, v3:V3D, v4:V3D)
Draw 3d quads using vertex.

### Clip3D(type:POLYTYPE, min_z:number, max_z:number, v:V3D[])
Clips the polygon given in `v'.

## ZBuffer
### zbuf = new ZBuffer()
Create ZBuffer for the current rendering Bitmap.

### zbuf = new ZBuffer(bm:Bitmap)
Create ZBuffer for the given Bitmap.

### zb.width
Width of ZBuffer

### zb.height
Height of ZBuffer

### zb.Set()
Set this ZBuffer as current rendering ZBuffer.

### zb.Clear(z)
Clear ZBuffer with given z value.
