Quad getPixel() or getPixels() not possible ?

[gcmartijn]

H!,

I have a quad and need the get the pixels or getPixel, but that is not possible ?

https://love2d.org/wiki/Quad

And https://love2d.org/wiki/love.image.newImageData don't allow a Quad

https://love2d.org/wiki/ImageData

Thanks for the info?

[pgimeno]

A quad is just a rectangle, so to say; it does not contain the image data itself, and you're right, ImageData does not support quads. But you can simulate it easily with Quad:getViewport:

Code: Select all

local function getQuadPixel(imgData, quad, x, y)
  local x0, y0 = quad:getViewport()
  return imgData:getPixel(x - x0, y - y0)
end

If that function could receive pixels outside the quad extents, and you want to do something about it, you'll have to account for the width and height of the quad as well:

Code: Select all

local function getQuadPixel(imgData, quad, x, y)
  local x0, y0, w, h = quad:getViewport()
  if x >= x0 and y >= y0 and x < x0 + w and y < y0 + h then
    return imgData:getPixel(x - x0, y - y0)
  end
  -- Do something to deal with coordinates out of the quad.
  -- In the example below, it reports an error.
  error("Coordinates out of the quad")
end

[gcmartijn]

Ah din't know about the quad viewport. Thanks!