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8315 :: pixie to direct read a seq[uint32]

• rforcen (orginal) [2021-08-10T09:16:34+02:00] view original

  having a seq[uint32] how can i directly create a pixie image ?

  i'm currently using a double for loop w/setRgbaUnsafe cast:

  
  for i in 0..<m.w:
          for j in 0..<m.h:
              image.setRgbaUnsafe(i,j, cast[ColorRGBX](m.image[i*m.w+j]))
  Run

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• ElegantBeef (orginal) [2021-08-10T10:14:11+02:00] view original

  Pixie has a `decodeImage` procedure which takes a seq[byte] assuming its a file format stored in memory. Otherwise the setting the data directly seems to be the best.

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• rforcen (orginal) [2021-08-10T10:27:21+02:00] view original

  this is used when you load an image file from memory:

  
  import pixie
  
  const imageIcon = "icon.png".staticRead
  
  let image = imageIcon.decodeImage
  # do something w/image...
  Run

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• treeform (orginal) [2021-08-10T19:11:37+02:00] view original

  ColorRGBX is the same size as uint32 - 4 bytes r, g, b, x (premultiplied alpha).

  So this cast is actually correct:

  image.data = cast[seq[ColorRGBX]](m.image)
  Run

  You might have to call toPremultipliedAlpha() after from pixie/internal if your image has alpha.

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