image data from pointer

[culurciello]

hi guys, how can I pass image data using a pointer to existing data? I see get pointer http://www.love2d.org/wiki/Data:getPointer but how do you PASS a pointer to EXISTING data?

[bartbes]

I don't think this is what you want to do, maybe you could tell us what you're trying to do?

[culurciello]

I have an image created by some other lua code - this tool: http://torch.ch/. It is in an array of memory. I need to display that image.

[slime]

Safe:

Code: Select all

local imagedata = love.image.newImageData(width, height)

imagedata:mapPixel(function(x, y, r, g, b, a)
    -- Get the rgba colors of your memory-image at the coordinates specified by x,y.
    return new_r, new_g, new_b, new_a
end)

image = love.graphics.newImage(imagedata)

Fast:

Code: Select all

local imagedata = love.image.newImageData(width, height)

local ptr, size = imagedata:getPointer(), imagedata:getSize()

-- Internally, all ImageData objects contain an array of 32-bit rgba pixels.
-- If you're absolutely sure your memory-image data matches up with that, you can use ffi.copy to efficiently copy the data to the ImageData via ImageData:getPointer.

image = love.graphics.newImage(imagedata)

[culurciello]

thanks "slime", your fast method is what i was looking for, the other one is too painfully slow!
thanks