DEFINE_UI_PARAMS(thresh, Threshold, DCTLUI_SLIDER_FLOAT, .02, 0.0, 1.0, 0.01)
DEFINE_UI_PARAMS(borderthresh, Border, DCTLUI_SLIDER_FLOAT, 100, 0, 100, 1)
DEFINE_UI_PARAMS(r, Red, DCTLUI_SLIDER_FLOAT, 1, 0.0, 1.0, 0.1)
DEFINE_UI_PARAMS(g, Green, DCTLUI_SLIDER_FLOAT, 0, 0.0, 1.0, 0.1)
DEFINE_UI_PARAMS(b, Blue, DCTLUI_SLIDER_FLOAT, 0, 0.0, 1.0, 0.1)

__DEVICE__ float3 transform(int p_Width, int p_Height, int p_X, int p_Y, float p_R, float p_G, float p_B)
{

   float sq = (p_Width * p_Width + p_Height * p_Height);
   float diag = _sqrtf(sq);   

   int border = round(diag * (100 - borderthresh) / 400);
   if (p_X < border || p_X > p_Width - border || p_Y < border || p_Y > p_Height - border || borderthresh >= 100) {
   if (p_R + p_G + p_B > thresh) {
      return (make_float3(p_R, p_G, p_B));
   } else {
      return (make_float3(r, g, b));
   }
   }
   else {
       return (make_float3(p_R, p_G, p_B));
   }

}