GPU

The GPU library is used to manipulate and draw on the screen.

Usage

local gpu = require("gpu")

-- Draw a magenta rectangle starting at 10, 15
-- of size 27x65 with a border size of 4 pixels
gpu.drawRectangle(10, 15, 27, 65, 0xff00ff, 4)

local width, height = gpu.getSize()
print(string.format("The screen size is %s by %s", width, height))

Warning

All coordinates start from 1, 1

Functions

getSize

gpu.getSize()

Get the size of the screen

Returns

1. width : integer - Width of screen
2. height : integer - Height of screen

setSize

gpu.setSize()

Set the size of the screen

Parameters

1. width : integer - Width of screen
2. height : integer - Height of screen

getScale

gpu.getScale()

Get the scale of the screen

Returns

1. scale : number - Scale of screen

setScale

gpu.setScale()

Set the scale of the screen

Parameters

1. scale : Number - Scale of screen

getPixel

gpu.getPixel( x, y )

Get the color of pixel at X,Y.

The color returned is black (#000000) if out of bounds.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.

Returns

1. color : integer - Decimal RGB color.

plot

gpu.plot( x, y, color )

Draw a pixel on the screen.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. color : integer - Decimal RGB color.

plots

gpu.plots( { x1, y1, x2, y2, ..., xn, yn}, color )

Draw multiple pixels on the screen.

Parameters

1. coordinates : number[] - Table containing pairs of coordinates.
2. color : integer - Decimal RGB color.

Throws

• If the coordinates table length is not even.
• If the coordinates table contains anything but numbers.

drawPoint

gpu.drawPoint( x, y, color, size? = 1)

Draw a square point.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. color : integer - Decimal RGB color.
4. size : number - Size of the pixel. Defaults to 1.

drawCircle

gpu.drawCircle( x, y, radius, color, size? = 1 )

Draw a circle.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. radius : numbeer - Radius of the circle.
4. color : integer - Decimal RGB color.
5. size : number - Border size.

drawLine

gpu.drawLine( startX, startY, endX, endY, color, size? = 1 )

Draw a line.

Parameters

1. startX : number - Start X coordinate.
2. startY : number - Start Y coordinate.
3. endX : number - End X coordinate.
4. endY : number - End Y coordinate.
5. color : integer - Decimal RGB color.
6. size : number - Thickness.

drawRectangle

gpu.drawRectangle( x, y, width, height, color, size? = 1 )

Draw a rectangle.

Tip

Setting border size to the smallest of width or height fills the rectangle.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. width : number - Width.
4. height : number - Height.
5. color : integer - Decimal RGB color.
6. size : number - Border size.

drawPolygon

gpu.drawPolygon( x, y, { x1, y1, x2, y2, ..., xn, yn}, color, size? = 1 )

Draw a polygon.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. points : number[] - Table containing pairs of coordinates to indicate the points.
4. color : integer - Decimal RGB color.
5. size : number - Border size.

Throws

• If the points table length is not even.
• If the points table contains anything but numbers.

drawEllipse

gpu.drawEllipse( x, y, radiusX, radiusY, color, size? = 1 )

Draw an ellipse.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. radiusX : number - Radius of X coordinate.
4. radiusY : number - Radius of Y coordinate.
5. color : integer - Decimal RGB color.
6. size : number - Border size.

drawString

gpu.drawString( x, y, color, text )

Draw a string.

Parameters

1. x : number - X coordinate.
2. y : number - Y coordinate.
3. color : integer - Decimal RGB color.
4. text : string - Text to draw.

measureString

gpu.measureString( text )

Get the bounds of the string.

Parameters

1. text : string - Text to measure.

Returns

1. width : number - Width of the text.
2. height : number - Height of the text.

getBuffer

gpu.getBuffer()

Get a unsigned 32-bit integer buffer of all colors in the screen in 0xRRGGBB format.

Returns

1. gpuBuffer : GPUBuffer - GPU Buffer

setBuffer

gpu.setBuffer( gpuBuffer )

Set the screen buffer.

Parameters

1. gpuBuffer : GPUBuffer - GPU Buffer

newBuffer

gpu.newBuffer( [width, height] )

Create a new empty buffer.

The buffer is already sized for the current screen size, unless width and height are defined.

Parameters

1. width : integer - Width of the buffer.
2. height : integer - Height of the buffer.

Returns

1. gpuBuffer : GPUBuffer - Empty GPU Buffer

drawBuffer

gpu.drawBuffer( buffer, x, y, width, height )

Draw a buffer to the screen at an arbitrary location.

Parameters

1. buffer : GPUBuffer - Buffer to draw
2. x : integer - X coordinate.
3. y : integer - Y coordinate.
4. width : integer - Width of the buffer.
5. height : integer - Height of the buffer.

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Last update: March 11, 2023
Created: March 11, 2023