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# OK-2007-07-05: Rewrote revRotatePoly and revPoints to fix bug 4882

# Parameters
#   pGraphic : A reference to a graphic
#   pAngle : The angle to rotate the graphic by
# Description
#   Performs a rotation transformation whose origin is the loc of the graphic and
#   whose magnitude is pAngle degrees. Preserves the topLeft of the graphic, but may
#   cause distortion due to rounding errors.
command revRotatePoly pGraphic, pAngle
    local tPoints, tFinalPoints
    local tLoc
    local tSinAngle, tCosAngle
    local tCurrentH, tCurrentV, tTransformedH, tTransformedV
    local tOrigLeft, tOrigTop
    
    lock screen
    lock messages
    if the realPoints of pGraphic is empty then
        put the effective points of pGraphic into tPoints
    else
        put the realPoints of pGraphic into tPoints
    end if
    put the loc of pGraphic into tLoc
    put item 1 of tLoc into tOrigLeft
    put item 2 of tLoc into tOrigTop
    put sin(pi*pAngle/180) into tSinAngle
    put cos(pi*pAngle/180) into tCosAngle
    repeat for each line tPoint in tPoints
        if tPoint is not empty then
            put item 1 of tPoint into tCurrentH
            put item 2 of tPoint into tCurrentV
            put (tOrigLeft+(tCosAngle*tCurrentH)-(tSinAngle*tCurrentV), tOrigTop+(tCosAngle*tCurrentV)+(tSinAngle*tCurrentH) ) after tFinalPoints
        end if
        put cr after tFinalPoints
    end repeat
    delete char -1 of tFinalPoints -- is CR
    if the style of pGraphic is among the items of "oval,rectangle,roundrect,regular" then
        set the style of pGraphic to "polygon"
    end if
    set points of pGraphic to tFinalPoints
    set the realPoints of pGraphic to tFinalPoints
    set loc of pGraphic to tLoc
    unlock messages
    unlock screen
end revRotatePoly

command revRotatePolygonOld pGraphic, pAngle
  local tTopLeft
  put the topLeft of pGraphic into tTopLeft
  
  local tPoints
  put revPoints(pGraphic) into tPoints
  
  local tLoc
  put the loc of pGraphic into tLoc
  
  local tSinAngle
  put sin(pAngle * (pi / 180)) into tSinAngle
  
  local tCosAngle
  put cos(pAngle * (pi / 180)) into tCosAngle
  
  local tLineCount
  put (the number of lines of tPoints) into tLineCount
  
  local tCurrentH, tCurrentV, tTransformedH, tTransformedV, tFinalPoints
  repeat for each line tPoint in tPoints
    if tPoint is empty then
      put empty & return after tFinalPoints
      next repeat
    end if 
    
    put item 1 of tPoint into tCurrentH
    put item 2 of tPoint into tCurrentV
    
    put trunc((tCosAngle * tCurrentH) - (tSinAngle * tCurrentV)) into tTransformedH
    put trunc((tSinAngle * tCurrentH) + (tCosAngle * tCurrentV)) into tTransformedV
    put tTransformedH + (item 1 of line 1 of tPoints) into tCurrentH
    put tTransformedV + (item 2 of line 1 of tPoints) into tCurrentV
    
    put tCurrentH,tCurrentV & return after tFinalPoints
  end repeat
  delete the last char of tFinalPoints
  
  set the points of pGraphic to tFinalPoints
  set the topLeft of pGraphic to tTopLeft
end revRotatePolygonOld

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set the realPoints of pGraphic to tFinalPoints