Screen#

Introduction#

The Screen methods control how the EXP Brain shows text, numbers, and graphics on its screen.

By default, the font for printing to the Brain is monospaced small which has 7 rows and 20 columns.

For drawing, the Brain’s resolution is 159 x 107 pixels.

A labeled grid diagram of the VEX Brain screen showing rows, columns, pixel dimensions, and coordinates, with red lines outlining the grid.

Below is a list of available methods:

Cursor Print – Display text and manage the print cursor.

  • print – Prints text, numbers, or variable values at the current cursor position.

  • print_at – Prints text, numbers, or variable values at specific x and y coordinates.

  • set_cursor – Moves the cursor to a specific row and column.

  • set_origin – Sets the origin used for coordinate-based printing and drawing.

  • next_row – Moves the cursor to the next row.

  • clear_row – Clears a row of text.

  • row – Returns the row where text will be printed.

  • column – Returns the column where text will be printed.

  • get_string_width – Returns the width of a string in pixels using the current font.

  • get_string_height – Returns the height of a string in pixels using the current font.

Mutators – Change screen settings, colors, and drawing behavior.

  • clear_screen – Clears all drawings and text from the Brain screen.

  • set_font – Sets the font type used for printing text on the Brain’s screen.

  • set_pen_width – Sets the thickness of drawn lines and shape outlines.

  • set_pen_color – Sets the color of text, pixels, lines, and shape outlines.

  • set_fill_color – Sets the fill color for drawn shapes and printed text backgrounds.

Draw – Create shapes, lines, and graphics on the Brain screen.

  • draw_pixel – Draws one pixel at a coordinate.

  • draw_line – Draws a line between two points.

  • draw_rectangle – Draws a rectangle using the current pen and fill colors.

  • draw_circle – Draws a circle using the current pen and fill colors.

  • draw_image_from_file – Draws an image from the SD card.

  • render – Switches drawing to double buffered and renders the Brain’s screen.

  • set_clip_region – Sets the clip region for drawing the supplied rectangle.

Cursor Print#

print#

print prints text, numbers, or variable values on the Brain screen at the current cursor position and font.

Usage:

brain.screen.print(text, sep, precision)

Parameters

Description

text

The text, number, or variable value to print.

sep

Optional. A string to inset between values. This must be written as a keyword argument (sep=). The default is “”.

precision

Optional. The number of decimal places to display when printing simple numbers. This must be written as a keyword argument(precision=). The default is 2.

 
brain.screen.print("Hello, Robot!")

A screenshot of the EXP Brain showing "Hello Robot" printed on the screen.

# Print the number 1 on the Brain's screen at current
# cursor position.
brain.screen.print(1)

# Print the numbers 1, 2, 3 and 4 on the Brain's screen at
# current cursor position separated by a '-'.
brain.screen.print(1, 2, 3, 4, sep='-')

set_cursor#

set_cursor moves the cursor to a specific row and column on the Brain screen. The next print call will start printing at that location. The row and column spacing will take into account the selected font. The default cursor position is Row 1, Column 1.

Usage:

brain.screen.set_cursor(row, column)

Parameters

Description

row

The row to move the cursor to.

column

The column to move the cursor to.

 
# Display text starting at Row 3 Column 10.
brain.screen.set_cursor(3, 10)
brain.screen.print("R3, C10")

A screenshot of the EXP Brain showing "R3, C10" printed on the screen.

set_origin#

set_origin sets the origin used for drawing and coordinate-based printing on the Brain screen. By default, the origin is the top-left corner of the screen.

Usage:

brain.screen.set_origin(x, y)

Parameters

Description

x

The origin’s x position relative to top left corner, from 0 to 159.

y

The origin’s y position relative to top left corner, from 0 to 107.

next_row#

next_row moves the cursor to column 1 on the next row on the Brain screen.

Usage:

brain.screen.next_row()

Parameters

Description

This method has no parameters.

 
# Display two lines of text.
brain.screen.print("Line 1")
brain.screen.next_row()
brain.screen.print("Line 2")

A screenshot of the EXP Brain showing the text "3" on row 3.

clear_row#

clear_row clears a single row of text on the Brain screen.

Usage:

brain.screen.clear_row(row)

Parameters

Description

row

Optional. The row to clear. The default is the current cursor row.

color

Optional. A valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Clear Brain's screen to black.
brain.screen.clear_row()

# Clear Brain's screen to blue using predefined color.
brain.screen.clear_row(2, Color.BLUE)

row#

row returns the row where text will be printed as an integer.

Usage:

brain.screen.row()

Parameters

Description

This method has no parameters.

 
# Display the cursor's current row.
brain.screen.set_cursor(3, 10)
brain.screen.print(brain.screen.row())

A screenshot of the EXP Brain showing the text "3" on row 3.

column#

column returns the column where text will be printed as an integer.

Usage:

brain.screen.column()

Parameters

Description

This method has no parameters.

 
# Display the cursor's current column.
brain.screen.set_cursor(3, 10)
brain.screen.print(brain.screen.column())

A screenshot of the EXP Brain showing the text "10" on column 10.

get_string_width#

get_string_width returns the width of a string in pixels as an integer, using the current font.

Usage:

brain.screen.get_string_width(string)

Parameters

Description

string

The string to measure.

get_string_height#

get_string_height returns the height of a string in pixels as an integer, using the current font.

Usage:

brain.screen.get_string_height(string)

Parameters

Description

string

The string to measure.

Mutators#

clear_screen#

clear_screen clears all drawings and text from the Brain’s screen.

Usage:

brain.screen.clear_screen(color)

Parameters

Description

color

Optional. A valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Print VEXcode on the Brain's screen.
brain.screen.print("VEXcode")

# Clear screen to black.
brain.screen.clear_screen()

# Print VEXcode on the Brain's screen.
brain.screen.print("VEXcode")

# Clear screen to blue using predefined color.
brain.screen.clear_screen(Color.BLUE)

set_font#

set_font sets the font used for displaying text on the Brain screen. This font will apply to all text printed after this method runs.

Usage:

brain.screen.set_font(fontname)

Parameters

Description

fontname

The font size (examples below):

  • MONO12
  • MONO15
  • MONO20
  • MONO30
  • MONO40
  • MONO60
  • PROP20
  • PROP30
  • PROP40
  • PROP60
Note: Extra small and small sizes are not available for proportional fonts.

The Brain's screen printed numbers and letters with size MONO 12 font. It shows A through Z and all numbers. On the bottom of the screen, it says 9 rows, 26 columns.
MONO12

The Brain's screen printed numbers and letters with size MONO 15 font. It shows A through T and all numbers. On the bottom of the screen, it says 7 rows, 22 columns.
MONO15

The Brain's screen printed numbers and letters with size MONO 20 font. It shows A through P and all numbers. On the bottom of the screen, it says 5 rows, 16 columns.
MONO20

The Brain's screen printed numbers and letters with size MONO 30 font. It shows A through J. On the bottom of the screen, it says R:3 C:10.
MONO30

The Brain's screen printed numbers and letters with size MONO 40 font. On the bottom of the screen, it says R:2 C:8.
MONO40

The Brain's screen printed numbers and letters with size MONO 60 font. Only MON60 is displayed.
MONO60

The Brain's screen printed numbers and letters with size PROP 20 font. It shows A through W and all numbers. On the bottom of the screen, it says 5 rows, 16 columns.
PROP20

The Brain's screen printed numbers and letters with size PROP 30 font. It shows A through P. On the bottom of the screen, it says R:3 C:10.
PROP30

The Brain's screen printed numbers and letters with size PROP 40 font. On the bottom of the screen, it says R:2 C:8.
PROP40

TThe Brain's screen printed numbers and letters with size PROP 60 font. Only PROP60 is displayed.
PROP60

 

# Set the font type to MONO40.
brain.screen.set_font(FontType.MONO40)
brain.screen.print("VEX")

A screenshot of the EXP Brain showing the text "VEX" in larger font than the default.

set_pen_width#

set_pen_width sets the thickness of drawn lines and shape outlines.

Usage:

brain.screen.set_pen_width(width)

Parameters

Description

width

The pen width, in pixels, from 0 to 32.

 
# Draw a rectangle with a pen width of 10.
brain.screen.set_pen_width(10)
brain.screen.draw_rectangle(20, 20, 75, 50)

A screenshot of the EXP Brain showing a rectangle with thick borders.

set_pen_color#

set_pen_color sets the color of text, pixels, lines, and shape outlines.

Usage:

brain.screen.set_pen_color(color)

Parameters

Description

color

The pen and font color to use. This can be a valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Draw a rectangle with orange borders.
brain.screen.set_pen_color(Color.ORANGE)
brain.screen.draw_rectangle(20, 20, 75, 50)

A screenshot of the EXP Brain showing a rectangle with orange borders.

# Set pen color red using a hex value.
brain.screen.set_pen_color(0xFF0000)

# Set pen color blue using predefined color.
brain.screen.set_pen_color(Color.BLUE)

# Set pen color green using web string.
brain.screen.set_pen_color("#00FF00")

set_fill_color#

set_fill_color sets the fill color used for drawing rectangles and circles.

Usage:

brain.screen.set_fill_color(color)

Parameters

Description

color

The fill color to use. This can be a valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Draw a purple rectangle.
brain.screen.set_fill_color(Color.PURPLE)
brain.screen.draw_rectangle(20, 20, 75, 50)

A screenshot of the EXP Brain showing a rectangle filled with purple.

# Set fill color red using a hex value.
brain.screen.set_fill_color(0xFF0000)

# Set fill color blue using predefined color.
brain.screen.set_fill_color(Color.BLUE)

# Set fill color green using web string.
brain.screen.set_fill_color("#00FF00")

Draw#

draw_pixel#

draw_pixel draws one pixel at the selected x and y coordinate using the current pen color.

Usage:

brain.screen.draw_pixel(x, y)

Parameters

Description

x

The x-coordinate to draw the pixel, from 0 to 159, referenced to the screen origin.

y

The y-coordinate to draw the pixel, from 0 to 107, referenced to the screen origin.

 
# Draw the pixels marking the corners of a square.
brain.screen.draw_pixel(50, 50)
brain.screen.draw_pixel(50, 75)
brain.screen.draw_pixel(75, 50)
brain.screen.draw_pixel(75, 75)

A screenshot of the EXP Brain showing an assortment of pixels showing the corners of a square.

draw_line#

draw_line draws a line from the first screen coordinate (x1, y1) to the second screen coordinate (x2, y2) using the current pen width and pen color.

Usage:

brain.screen.draw_line(x1, y1, x2, y2)

Parameters

Description

x1

The x-coordinate in pixels of the start of the line, from 0 to 159, referenced to the screen origin.

y1

The y-coordinate in pixels of the start of the line, from 0 to 107, referenced to the screen origin.

x2

The x-coordinate in pixels of the end of the line, from 0 to 159, referenced to the screen origin.

y2

The y-coordinate in pixels of the end of the line, from 0 to 107, referenced to the screen origin.

 
# Draw a line from the top left to bottom right of the screen.
brain.screen.draw_line(0, 0, 159, 107)

The Brain's screen shows a thin diagonal line across the center, from the upper left corner to the lower right corner.

draw_rectangle#

draw_rectangle draws a rectangle using the current pen width, pen color, and fill color, unless the optional color parameter is used.

Usage:

brain.screen.draw_rectangle(x, y, width, height, color)

Parameters

Description

x

The x-coordinate in pixels of the top-left corner of the rectangle, from 0 to 159, referenced to the screen origin.

y

The y-coordinate in pixels of the top-left corner of the rectangle, from 0 to 107, referenced to the screen origin.

width

The width of the rectangle.

height

The height of the rectangle.

color

Optional. A valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Draw a rectangle on the screen.
brain.screen.draw_rectangle(20, 20, 80, 30)

The Brain's screen shows a rectangle with a thin white border on the screen.

# Draw a green rectangle on the screen that is filled using blue.
brain.screen.set_pen_color(Color.GREEN)
brain.screen.set_fill_color(Color.BLUE)
brain.screen.draw_rectangle(10, 10, 20, 20)

# Draw a green rectangle on the screen that is filled using red.
brain.screen.set_pen_color(Color.GREEN)
brain.screen.draw_rectangle(50, 50, 20, 20, Color.RED)

draw_circle#

draw_circle draws a circle using the current pen width, pen color, and fill color, unless the optional color parameter is used.

Usage:

brain.screen.draw_circle(x, y, radius, color)

Parameters

Description

x

The x-coordinate in pixels of the center of the circle, from 0 to 159, referenced to the screen origin.

y

The y-coordinate in pixels of the center of the circle, from 0 to 107, referenced to the screen origin.

radius

The radius of the circle.

color

Optional. A valid ColorType, a hex value, or a web string.

  • Color.BLACK
  • Color.BLUE
  • Color.GREEN
  • Color.ORANGE
  • Color.PURPLE
  • Color.RED
  • Color.VIOLET
  • Color.WHITE
  • Color.YELLOW
You can also specify a custom color.

 
# Draw a circle on the screen.
brain.screen.draw_circle(80, 50, 20)

The Brain's screen shows a circle with a thin white border drawn in the center.

# Draw a green circle on the Brain's screen that is filled using blue.
brain.screen.set_pen_color(Color.GREEN)
brain.screen.set_fill_color(Color.BLUE)
brain.screen.draw_circle(50, 50, 10)

# Draw a green circle on the Brain's screen that is filled using red.
brain.screen.set_pen_color(Color.GREEN)
brain.screen.draw_circle(100, 50, 10, Color.RED)

draw_image_from_file#

draw_image_from_file draws an image from the SD card. The filename you put when calling the method must be located on the SD card.

Usage:

brain.screen.draw_image_from_file(filename, x, y)

Parameters

Description

filename

The filename of the image.

x

The x coordinate for the top-left corner of the image on the screen.

y

The y coordinate for the top-left corner of the image on the screen.

 
# Draw the vex.bmp image on the Brain's screen at coordinate 0, 0.
brain.screen.draw_image_from_file('vex.bmp', 0, 0)

render#

render switches drawing to double buffered and renders the Brain’s screen. Once called, further drawing will not appear on the Brain’s screen until the next time render is called.

  • True if buffer was successfully rendered to the screen.

  • False if buffer was not successfully rendered to the screen.

Usage:

brain.screen.render()

Parameters

Description

This method has no parameters.

set_clip_region#

set_clip_region defines a rectangular area on the screen where all drawings and text will be confined. Any content outside this region will not be displayed.

Usage:

brain.screen.set_clip_region(x, y, width, height)

Parameters

Description

x

The x position of the top-left corner of the rectangle, referenced to the screen origin.

y

The y position of the top-left corner of the rectangle, referenced to the screen origin.

width

The width of the rectangle.

height

The height of the rectangle.
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