屏幕

介绍

The VEX IQ (2nd gen) Brain screen provides a variety of methods to display information, draw shapes, and control the visual elements of the screen.

This page uses brain as the example Brain name. Replace it with your own configured name as needed.

以下是所有方法的列表：

Cursor Print — Place and print text.

• print — Prints text at the current cursor position.

• set_cursor — Sets the cursor to a specific row and column.

• next_row — Moves the cursor to column 1 of the next row.

• clear_row — Clears a row of text.

• row — Returns the current cursor row.

• column — Returns the current cursor column.

• print_at — Prints text at a specific x and y location.

• get_string_width — Returns the width of a string.

• get_string_height — Returns the height of a string.

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

• clear_screen — Clears the screen of all drawings and text.

• set_font — Sets the font for printed text.

• set_pen_width — Sets the thickness for drawn shapes and lines.

• set_pen_color — Sets the color for outlines and text.

• set_fill_color — Sets the fill color for shapes and backgrounds.

• set_origin — Sets a new origin for printing and drawing.

Draw — Add graphics to the screen.

• draw_pixel — Draws a pixel at a specific x and y location.

• draw_line — Draws a line between two points.

• draw_rectangle — Draws a rectangle.

• draw_circle — Draws a circle.

• set_clip_region — Restricts where drawings and text can appear.

• render — Updates the Brain’s screen with text and drawings only when called.

光标打印

print

print displays text on the Brain’s screen at the current cursor position and font.

Usage:
brain.screen.print(text, precision, opaque)

参数	描述
text	要在屏幕上显示的文本、数字或变量值。
precision	Optional. The number of decimal places to display when displaying numbers. This must be written as a keyword argument, ie:precision=3. Default is 2.
opaque	Optional. opaque=True — The background of the text will be filled with the current fill color or black by default. opaque=False (default) — The background of the text will match the screen’s background color.

# Display a message at the starting 
# cursor position
brain.screen.print("Hello, Robot!")

# Display a percentage with 4 decimal 
# places and a blue background
brain.screen.set_fill_color(Color.BLUE)
brain.screen.print((42/100), precision = 4, opaque = True)

set_cursor

set_cursor sets the cursor at a specific row and column on the Brain’s screen. How many rows and columns can comfortably fit depends on the selected font.

Monospaced fonts have characters that are all the same width, making text placement consistent. In contrast, proportional fonts vary in character width, so some letters take up more space than others. However, regardless of which type is used, set_cursor positions the cursor based on row and column size, not font style. The font size can be adjusted using set_font.

Usage:
brain.screen.set_cursor(row, column)

参数	描述
row	游标所在行。
column	光标所在的列。

# Repeatedly print the Brain's timer at 
# the top left of the screen
while True:
    brain.screen.print(brain.timer.time(SECONDS))
    brain.screen.next_row()
    wait(1, SECONDS)
    brain.screen.clear_screen()
    brain.screen.set_cursor(1, 1)

next_row

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

Usage:
brain.screen.next_row()

参数	描述
	该方法没有参数。

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

clear_row

clear_row clears a row of drawings and text on the Brain’s screen.

Usage:
brain.screen.clear_row(row, color)

参数	描述
排	可选。要清除的行。默认值为当前光标所在行。
颜色	Optional. The color to apply to the cleared row. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

# Display text on two rows
brain.screen.print("This text stays")
brain.screen.next_row()
brain.screen.print("This disappears")

# Wait 3 seconds before clearing 
# only the second row
wait(3, SECONDS)
brain.screen.clear_row()

# Turn the 5th row green
brain.screen.clear_row(5, Color.GREEN)

row

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

Usage:
brain.screen.row()

参数	描述
	该方法没有参数。

# Set cursor to (3,2) and print 
# row number
brain.screen.set_cursor(3, 2)
brain.screen.print(brain.screen.row())

column

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

Usage:
brain.screen.column()

参数	描述
	该方法没有参数。

# Set cursor to (3,2) and print 
# column number
brain.screen.set_cursor(3, 2)
brain.screen.print(brain.screen.column())

print_at

print_at displays text on the Brain’s screen at a specified x and y-coordinate (in pixels) with the currently set font and set origin. This method disregards the current cursor position.

Usage:
brain.screen.print_at(text, x, y, precision, opaque)

参数	描述
text	要打印的文本。
x	The x position to print at as a keyword argument, ie: x=, referenced to the screen origin.
y	The y position to print at as a keyword argument, ie: y=, referenced to the screen origin.
precision	Optional. The number of decimal places to display when displaying numbers. This must be written as a keyword argument, ie:precision=3. Default is 2.
opaque	Optional. opaque=True — The background of the text will be filled with the current fill color or black by default. opaque=False (default) — The background of the text will match the screen’s background color.

# Print the number 1 on the Brain's screen at position (100, 40)
brain.screen.print_at(1, x=100, y=40)

# Display 1/3 with 3 decimal places and a blue background
brain.screen.set_fill_color(Color.BLUE)
brain.screen.print_at((1/3), x=100, y=40, precision=3, opaque=True)

get_string_width

get_string_width returns the width of a string in pixels, as it would appear on the Brain’s screen. The width varies depending on the string’s length and the current font.

Usage:
brain.screen.get_string_width(string)

参数	描述
string	要测量的字符串。

get_string_height

get_string_height returns the height of a string in pixels, as it would appear on the Brain’s screen. The width varies depending on the string’s length and the current font.

Usage:
brain.screen.get_string_height(string)

参数	描述
string	要测量的字符串。

修改器

clear_screen

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

Usage:
brain.screen.clear_screen(color)

参数	描述
color	Optional. Sets the screen color. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

# Draw a circle and clear it after 
# 2 seconds
brain.screen.draw_circle(80, 50, 20)
wait(2, SECONDS)
brain.screen.clear_screen()

# Turn the screen red
brain.screen.clear_screen(Color.RED)

set_font

set_font sets the font used for displaying text on the Brain’s screen. This font will apply to all text printed with print or print_at. The default font at the start of a project is MONO20.

Usage:
brain.screen.set_font(fontname)

范围	描述
fontname	Sets the font to one of the following: MONO12 MONO15 MONO20 MONO30 MONO40 MONO60 PROP20 PROP30 PROP40 PROP60 These options are shown below.

MONO12	MONO15	MONO20
MONO30	MONO40	MONO60
PROP20	PROP30	PROP40
PROP60

# Display two different fonts on 
# two separate lines
brain.screen.set_font(FontType.MONO20)
brain.screen.print("Mono Medium")
brain.screen.next_row()
brain.screen.set_font(FontType.PROP20)
brain.screen.print("Prop Medium")

set_pen_width

set_pen_width sets the pen width used for drawing lines and shapes.

Usage:
brain.screen.set_pen_width(width)

范围	描述
width	笔的宽度，以像素为单位的整数，范围是 0 到 32。

# Draw two circles with 
# different pen widths
brain.screen.draw_circle(40, 70, 20)
brain.screen.set_pen_width(5)
brain.screen.draw_circle(100, 70, 20)

set_pen_color

set_pen_color sets the pen color used for drawing lines, shapes, and text.

Usage:
brain.screen.set_pen_color(color)

范围	描述
color	Optional. Sets the pen color. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

# Draw two rectangles with 
# different colors
brain.screen.draw_rectangle(100, 50, 10, 20)
brain.screen.set_pen_color(Color.BLUE)
brain.screen.draw_rectangle(50, 50, 10, 20)

set_fill_color

set_fill_color method sets the fill color used when shapes are drawn.

Usage:
brain.screen.set_fill_color(color)

范围	描述
color	Optional. Sets the fill color. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

# Draw a yellow circle
brain.screen.set_fill_color(Color.YELLOW)
brain.screen.draw_circle(50, 50, 20)

set_origin

set_origin sets the origin (0,0) used for drawing or printing on the Brain’s screen. By default, drawing or printing methods consider the top left corner of the screen as the origin. This method can reset the origin to an alternate (x, y) screen coordinate location.

Usage:
brain.screen.set_origin(x, y)

范围	描述
x	设置为原点的新 x 坐标，以 0 至 160 之间的整数形式给出。
y	设置作为原点的新 y 坐标，以 0 至 108 之间的整数形式给出。

# Draw a line with the origin set to (50, 50)
brain.screen.set_origin(50, 50)
brain.screen.draw_line(1, 1, 159, 107)

画

draw_pixel

draw_pixel draws a pixel at the specified (x, y) screen coordinate in the current pen color. It uses the current pen color set by set_pen_color.

Usage:
brain.screen.draw_pixel(x, y)

范围	描述
x	将绘制像素的 x 坐标，以 0 至 160 之间的整数表示。
y	将绘制像素的 y 坐标，以 0 至 108 之间的整数表示。

# Draw one pixel at the center 
# of the screen
brain.screen.draw_pixel(80, 50)

draw_line

draw_line draws a line from the first specified screen coordinate (x1, y1) to the second specified screen coordinate (x2, y2). It uses the current the pen width set by set_pen_width and pen color set by set_pen_color.

The x and y-coordinates use the default origin of (0, 0) unless a different origin has been set using set_origin.

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

范围	描述
x1	线的起始 x 坐标，以 0 至 160 之间的整数表示。
y1	线的起始 y 坐标，以 0 至 108 之间的整数表示。
x2	线的结束 x 坐标，以 0 至 160 之间的整数表示。
y2	线的结束 y 坐标，以 0 至 108 之间的整数表示。

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

draw_rectangle

draw_rectangle draws a rectangle with its top-left corner at the specified (x, y) coordinate and a size determined by the given width and height, all measured in pixels. The rectangle’s outline is drawn using the current pen width set by set_pen_width and the pen color set by set_pen_color. The interior is filled with the color set by set_fill_color.

The x and y-coordinates use the default origin of (0,0) unless a different origin has been set using set_origin.

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

范围	描述
x	矩形左上角的 x 坐标，以 0 至 160 之间的整数表示。
y	矩形左上角的 y 坐标，以 0 至 108 之间的整数表示。
width	矩形的宽度，以 0 到 160 之间的整数表示。
height	矩形的高度，以 0 到 108 之间的整数表示。
color	Optional. The fill color of the rectangle. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

# Draw a red rectangle on the screen
brain.screen.draw_rectangle(25, 25, 100, 50, Color.RED)

draw_circle

draw_circle draws a circle with its center at the specified (x, y) coordinate and a size determined by the given radius, all measured in pixels. The circle’s outline is drawn using the current pen width set by set_pen_width and the pen color set by set_pen_color. The interior is filled with the color set by set_fill_color.

The x and y-coordinates use the default origin of (0,0) unless a different origin has been set using set_origin.

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

范围	描述
x	圆心的 x 坐标，以 0 至 160 之间的整数表示。
y	圆心的 y 坐标，以 0 至 160 之间的整数表示。
radius	圆的半径，以 0 到 108 像素之间的整数表示。
color	Optional. The fill color of the circle. Options include: Color.BLACK Color.BLUE Color.BLUE_GREEN Color.BLUE_VIOLET Color.GREEN Color.ORANGE Color.PURPLE Color.RED COLOR.RED_ORANGE Color.RED_VIOLET Color.VIOLET Color.WHITE Color.YELLOW Color.YELLOW_GREEN Color.YELLOW_ORANGE You can also specify a custom color.

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

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)

范围	描述
x	剪辑区域左上角的 x 坐标，以 0 到 160 之间的整数或浮点数给出。
y	剪辑区域左上角的 y 坐标，以 0 到 108 之间的整数或浮点数给出。
width	剪辑区域的宽度（以像素为单位），以 0 到 160 之间的整数或浮点数表示。
height	剪辑区域的高度（以像素为单位），以 0 到 108 之间的整数或浮点数表示。

# Restrict text and drawings to a specific region
brain.screen.set_clip_region(0, 0, 120, 120)
brain.screen.draw_rectangle(60, 60, 100, 100, Color.RED)
brain.screen.print_at("Cut off!", x=60, y=60)

render

render enables double buffering for the Brain’s screen. Once called, any drawing commands (like text, shapes, or images) will no longer appear immediately for the rest of the project. Instead, updates will only be shown when render is used again. This allows for smoother and more controlled screen updates, but means nothing will be visible until render is used.

Usage:
brain.screen.render()

参数	描述
	该方法没有参数。

# Render text after moving
brain.screen.render()
brain.screen.print("Render later...")
drivetrain.drive_for(FORWARD, 100, MM)
drivetrain.turn_for(RIGHT, 90, DEGREES)
brain.screen.render()