Package 'tigerfb'

Capture the current window contents to a native raster image

Description

Capture the current window contents to a native raster image

Usage

fb_capture(window)

Arguments

window

window handle as created by fb_open()

Value

A native raster image

See Also

Other capturing functions: fb_save_png()

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
nr <- fb_capture(window)
Sys.sleep(3)
fb_close(window)
class(nr)

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Destroy window in a safe manner.

Description

This will reconnect to the specified window and prompt the user to close the window.

Usage

fb_close(window)

Arguments

window

window handle as created by fb_open()

Value

None

See Also

Other core window functions: fb_open(), fb_update()

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

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Bubble universe demonstration.

Description

This demo generates an animation of an evolving bubble universe.

Usage

fb_demo(...)

Arguments

...	arguments passed to fb_open()

Details

Press 'ESC' key to quit, and then close the window.

Value

None

Examples

fb_demo(mode = 'fullscreen')

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Clear window

Description

Clear window

Usage

fb_fill(window, fill)

Arguments

window	window handle as created by fb_open()
fill	Fill color. Default: NA (transparent)

Value

None

See Also

Other drawing commands: fb_line(), fb_rect(), fb_text()

Examples

window <- fb_open(100, 100)
fb_fill(window, 'hotpink') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

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Check if a window is currently open and active

Description

Check if a window is currently open and active

Usage

fb_is_open(window)

Arguments

window

window handle as created by fb_open()

Value

Logical value

Examples

window <- fb_open()
fb_is_open(window)
fb_close(window)
fb_is_open(window)

---

Get the list of key names which are returned by fb_state()

Description

Get the list of key names which are returned by fb_state()

Usage

fb_key_names()

Value

character vector

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Draw Line

Description

Draw Line

Usage

fb_line(window, x1, y1, x2, y2, color = "black")

Arguments

window	window handle as created by fb_open()
x1, y1, x2, y2	line coordinates
color	Color. Default: 'black'

Value

None

See Also

Other drawing commands: fb_fill(), fb_rect(), fb_text()

Examples

window <- fb_open(100, 100)
fb_line(window, 0, 0, 50, 50, 'hotpink') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

---

Initialise an interactive window

Description

Initialise an interactive window

Usage

fb_open(
  width = 150,
  height = 100,
  mode = "auto",
  expand = 2,
  cursor = TRUE,
  title = "R"
)

Arguments

width, height	Initial window dimensions (in pixels)
mode	Window mode. Valid values:'auto', 'fixed', 'fullscreen'. Default: "auto" resizes the underlying image canvas when image is resized. "fixed" always keeps the same sized image canvas, but applies an integer scaling factor to maximize the display within the window.
expand	Integer value to expand pixel size. Only valid when mode = "auto". Valid values: 1, 2, 3, 4. Default: 2
cursor	show the cursor? Default: TRUE
title	window title. Default: "R"

Value

Window handle

See Also

Other core window functions: fb_close(), fb_update()

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

---

Draw rectangle

Description

Draw rectangle

Usage

fb_rect(window, x, y, w, h, color = "black", fill = NA)

Arguments

window	window handle as created by fb_open()
x, y, w, h	location and dimensions of rectangle
color	Outline color. Default: 'black'
fill	Fill color. Default: NA (transparent)

Value

None

See Also

Other drawing commands: fb_fill(), fb_line(), fb_text()

Examples

window <- fb_open(100, 100)
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

---

Capture the current window contents to a PNG file

Description

Capture the current window contents to a PNG file

Usage

fb_save_png(window, filename)

Arguments

window	window handle as created by fb_open()
filename	PNG filename

Value

None

See Also

Other capturing functions: fb_capture()

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
png_file <- tempfile(fileext = ".png")
fb_save_png(window, png_file)
Sys.sleep(3)
fb_close(window)

---

Get the state of the current window i.e. keys and mouse

Description

Get the state of the current window i.e. keys and mouse

Usage

fb_state(window)

Arguments

window

window handle as created by fb_open()

Value

environment of 'mouse' and 'key' information

mouse$coords

integer vector of (x,y) coordinates

mouse$buttons

integer vector of the state of three mouse buttons. Value represents the state of the button. See ?press_state for details

key

named integer vector of all keycodes. Value represents the state of the key. See ?press_state for details

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
for (i in seq(30)) {
  fb_update(window)
  state <- fb_state(window)
  print(state$mouse$coords)
  Sys.sleep(0.1)
}
print(state)
fb_close(window)

---

Draw Text using built-in font

Description

Draw Text using built-in font

Usage

fb_text(window, x, y, text, color = "white")

Arguments

window	window handle as created by fb_open()
x, y	position
text	string
color	Color. Default: 'white'

Value

None

See Also

Other drawing commands: fb_fill(), fb_line(), fb_rect()

Examples

window <- fb_open(100, 100)
fb_text(window, 6, 42, "Hello #RStats!") 
fb_update(window)
Sys.sleep(3)
fb_close(window)

---

Update window display

Description

Execute any queued drawing commands. User can also provide a new native raster image which will replace the current window contents

Usage

fb_update(window, nr = NULL)

Arguments

window	window handle as created by fb_open()
nr	(optional) native raster image the same dimensions as the window. This will be rendered over the top of the current contents of the window. Default: NULL means to only process the drawing queue, and update the keyboard and mouse state.

Value

None

See Also

Other core window functions: fb_close(), fb_open()

Examples

window <- fb_open()
fb_rect(window, 10, 10, 70, 30, 'hotpink', 'blue') 
fb_update(window)
Sys.sleep(3)
fb_close(window)

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Status codes for mouse and keyboard

Description

Keys and mouse buttons may be 4 different states - not pressed, held down, has just transitioned from not-pressed-to-pressed, and has just transitioned from pressed-to-not-pressed.

Usage

press_state

Details

There 4 possible key states returned by fb_state(). For simple keyboard/mouse scanning the user need only check if the state is non-zero to indicate that the key or mouse button has been pressed.

For some complex handling, the user-interface may need to watch for a transition event i.e. from-pressed-to-not-pressed, or from-not-pressed-to-pressed (e.g. keyboard control in Doom)

0 = INACTIVE

The key/button is not pressed

1 = DOWN

The key/button has just now been pressed down

2 = HELD

The key/button is being held down

3 = UP

The key/button was being held but has just now been released

Examples

press_state[["INACTIVE"]]
press_state[["DOWN"]]
press_state[["HELD"]]
press_state[["UP"]]

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More palatable printing of a 'state' environment

Description

More palatable printing of a 'state' environment

Usage

## S3 method for class 'tigerfb_state'
print(x, ...)

Arguments

x	state object returned by fb_state()
...	ignored

Value

original x

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