// V-Plotter calculations by 'jurs' for German Arduino Forum
// Details: http://forum.arduino.cc/index.php?topic=226277.0

#define XB 500.0
#define XA XB
#define YB 600.0
#define YA YB

void calc_ab(float x, float y, float &da, float &db)
{
  // db = b - b0
  db= sqrt((XA-x)*(XA-x) + (YA-y)*(YA-y)) - sqrt(YA*YA+XA*XA);
  // da = a - a0
  da= sqrt((XB+x)*(XB+x) + (YB-y)*(YB-y)) - sqrt(YB*YB+XB*XB);
}

void plan_buffer_line(float xx, float yy, float z, float feed_rate, uint8_t invert_feed_rate) 
{
  // Prepare to set up new block
  block_t *block = &block_buffer[block_buffer_head];
  float x,y;
  calc_ab(xx, yy, x, y);
  // Calculate target position in absolute steps