On 9/5/2015 2:42 AM, Peter Reid wrote:
5. Here is the handler that I use to test the colour of a pixel:
function getPixelColour pX, pY, pImgWidth
local tPix, tImgPos, tRedVal, tGreenVal, tBlueVal
put pY * pImgWidth + pX into tPix
put tPix * 4 into tImgPos
put charToNum(byte (tImgPos + 2) of image "graph" of stack "ImageHolder")
into tRedVal
put charToNum(byte (tImgPosn + 3) of image "graph" of stack "ImageHolder")
into tGreenVal
put charToNum(byte (tImgPosn + 4) of image "graph" of stack "ImageHolder")
into tBlueVal
return (tRedVal) -- & comma & tGreenVal & comma & tBlueVal)
end getPixelColour
I wouldn't think the width of the image would matter in the calculation
if you're counting downward in a straight line. I think it should be
more like this:
put pX,pY+1 into tPix
There's a hack to get a pixel color that might work a little faster, and
would reduce the handler to 2 lines:
function getPixelColour pX, pY
set the screenMouseloc to globalLoc(pX,pY)
return the mousecolor -- or: item 1 of the mousecolor
end getPixelColour
Normally you'd store the original mouseloc and then restore it again
after getting the mousecolor, but in this case I wouldn't restore it
until the loop is done and you've found the bottom edge.
--
Jacqueline Landman Gay | jac...@hyperactivesw.com
HyperActive Software | http://www.hyperactivesw.com
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