Difference between revisions of "ImageData:getPixel"

 
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Gets the color of a pixel at a specific position in the image.
  
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Valid x and y values start at 0 and go up to image width and height minus 1. Non-integer values are floored.
  
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In versions prior to [[11.0]], color component values were within the range of 0 to 255 instead of 0 to 1.
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{{notice|Prior to [[0.10.2]], this function does not properly handle non-integer coordinates, and may produce an invalid result when non-integer values are passed.}}
 
== Function ==
 
== Function ==
 
=== Synopsis ===
 
=== Synopsis ===
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{{param|number|y|The position of the pixel on the y-axis.}}
 
{{param|number|y|The position of the pixel on the y-axis.}}
 
=== Returns ===
 
=== Returns ===
{{param|number|r|The red component (0-255).}}
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{{param|number|r|The red component (0-1).}}
{{param|number|g|The green component (0-255).}}
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{{param|number|g|The green component (0-1).}}
{{param|number|b|The blue component (0-255).}}
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{{param|number|b|The blue component (0-1).}}
{{param|number|a|The alpha component (0-255).}}
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{{param|number|a|The alpha component (0-1).}}
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== Examples ==
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When the mouse is clicked, reads the red, green, and blue value of the pixel under the mouse and uses it as the background color.
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<source lang="lua">
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local imagedata = love.image.newImageData('path/to/Image.png')
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local image    = love.graphics.newImage(imagedata)
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function love.mousepressed(mx, my)
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    if  0 <= mx and mx < image:getWidth()
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    and 0 <= my and my < image:getHeight() then
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        local r, g, b = imagedata:getPixel(mx, my)
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        love.graphics.setBackgroundColor(r, g, b)
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    end
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end
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function love.draw()
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    love.graphics.draw(image, 0, 0)
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end
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</source>
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== See Also ==
 
== See Also ==
 
* [[parent::ImageData]]
 
* [[parent::ImageData]]
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* [[ImageData:setPixel]]
 
[[Category:Functions]]
 
[[Category:Functions]]
{{#set:Description=}}
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{{#set:Description=Gets the color of a pixel.}}
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{{#set:Since=000}}
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== Other Languages ==
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{{i18n|ImageData:getPixel}}

Latest revision as of 09:25, 14 January 2019

Gets the color of a pixel at a specific position in the image.

Valid x and y values start at 0 and go up to image width and height minus 1. Non-integer values are floored.

In versions prior to 11.0, color component values were within the range of 0 to 255 instead of 0 to 1.

O.png Prior to 0.10.2, this function does not properly handle non-integer coordinates, and may produce an invalid result when non-integer values are passed.  


Function

Synopsis

r, g, b, a = ImageData:getPixel( x, y )

Arguments

number x
The position of the pixel on the x-axis.
number y
The position of the pixel on the y-axis.

Returns

number r
The red component (0-1).
number g
The green component (0-1).
number b
The blue component (0-1).
number a
The alpha component (0-1).

Examples

When the mouse is clicked, reads the red, green, and blue value of the pixel under the mouse and uses it as the background color.

local imagedata = love.image.newImageData('path/to/Image.png')
local image     = love.graphics.newImage(imagedata)

function love.mousepressed(mx, my)
    if  0 <= mx and mx < image:getWidth()
    and 0 <= my and my < image:getHeight() then
        local r, g, b = imagedata:getPixel(mx, my)
        love.graphics.setBackgroundColor(r, g, b)
    end
end

function love.draw()
    love.graphics.draw(image, 0, 0)
end

See Also


Other Languages