Form manipulation from a Plugin

diegogomezdeck at diegogomezdeck at
Mon Apr 7 13:57:33 UTC 2003

Hi list...

I'm processing a 32 bits Form in a slang-plugin.

The method receive the Form as a parameter:

   formOop := interpreterProxy stackObjectValue: 1.

Then I ask for widht, height and a pointer to bits:

   bits := interpreterProxy fetchPointer: 0 ofObject: formOop.
   width := self fetchIntOrFloat: 1 ofObject: formOop.
   height := self fetchIntOrFloat: 2 ofObject: formOop.

Then I iterate over the bits:

      to: bits + (height - 1 * (width * 4))
      by: 4
      do: [:pos |
         pixel := interpreterProxy longAt: pos.
         alpha := (pixel bitAnd: 16rFF000000) >> 24.
         <some other stuff>

The problem I have is the following: The alpha part of pixel is always 0.
(I don't need to say that the form has not transparent colors)

Any idea of my problem?


Diego Gomez Deck

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