/*
*********************************************************************************************************
*                                                uC/GUI
*                        Universal graphic software for embedded applications
*
*                       (c) Copyright 2002, Micrium Inc., Weston, FL
*                       (c) Copyright 2002, SEGGER Microcontroller Systeme GmbH
*
*              礐/GUI is protected by international copyright laws. Knowledge of the
*              source code may not be used to write a similar product. This file may
*              only be used in accordance with a license and should not be redistributed
*              in any way. We appreciate your understanding and fairness.
*
----------------------------------------------------------------------
File        : GUI_DrawPolyline.c
Purpose     : Implementation of GUI_DrawPolyline (part of emWin GSC)
---------------------------END-OF-HEADER------------------------------
*/

#include <stddef.h>           /* needed for definition of NULL */
#include "GUI_Protected.h"

static void _DrawGraph(I16 *pay, int NumPoints, int xOff, int yOff) {
  int i;
  int y0, y1;
  int yClip0, yClip1;
  /* Perform high level clipping in x */
  yClip0 = GUI_Context.pClipRect_HL->y0;
  yClip1 = GUI_Context.pClipRect_HL->y1;
  i=0;
  if (GUI_Context.pClipRect_HL) {
    if (xOff < GUI_Context.pClipRect_HL->x0)
      i = GUI_Context.pClipRect_HL->x0 - xOff;
    if (xOff+NumPoints-1 > GUI_Context.pClipRect_HL->x1)
      NumPoints = GUI_Context.pClipRect_HL->x1 - xOff + 1;
  }
  /* Start drawing if there is something left to do after x-clipping */
  if (i < NumPoints) {
    y0 = *(pay + i++) + yOff;
    /* Iterate */
    for (; i < NumPoints; i++) {
      /* Perform high level clipping in y */
      y1 = *(pay + i) + yOff;
      if ((y0 >= yClip0) | (y1 >= yClip0)) {
        if ((y0 <= yClip1) | (y1 <= yClip1)) {
          int y01;
          y01 = (y1 + y0) / 2;
          if (y0 <= y1) {
            LCD_DrawVLine(i + xOff - 1, y0, y01);
            LCD_DrawVLine(i + xOff, y01, y1);
          } else {
            LCD_DrawVLine(i + xOff - 1, y01, y0);
            LCD_DrawVLine(i + xOff, y1, y01);
          }
        }
      }
      y0 = y1;
    }
  }
}
  
void GUI_DrawGraph(I16 *pay, int NumPoints, int x0, int y0) {
  GUI_LOCK();
  #if (GUI_WINSUPPORT)
    WM_ADDORG(x0,y0);
    WM_ITERATE_START(NULL); {
  #endif
  _DrawGraph(pay, NumPoints, x0, y0);
  #if (GUI_WINSUPPORT)
    } WM_ITERATE_END();
  #endif
  GUI_UNLOCK();
}