/*
*********************************************************************************************************
*                                             uC/GUI V3.98
*                        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_DrawGraphEx.c
Purpose     : Implementation of GUI_DrawGraphEx
---------------------------END-OF-HEADER------------------------------
*/

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

/*********************************************************************
*
*       Defines
*
**********************************************************************
*/
#define SWAPSIGN        1
#define SWAPSIGN_DIVIDE 2
#define DIVIDE          3
#define MULTIPLY        4
#define MULTIPLY_DIVIDE 5

/*********************************************************************
*
*       Static code
*
**********************************************************************
*/
/*********************************************************************
*
*       _DrawGraph
*/
static void _DrawGraph(I16 * pay, int NumPoints, int xOff, int yOff, int Numerator, int Denominator) {
  int i;
  int y0, y1;
  int yClip0, yClip1;
  int Method;
  /* Perform high level clipping in x */
  yClip0 = GUI_Context.pClipRect_HL->y0;
  yClip1 = GUI_Context.pClipRect_HL->y1;
  if ((Numerator == 0) || (Denominator == 0) || (NumPoints <= 0)) {
    return;
  }
  if (Numerator == -1) {
    if (Denominator == 1) {
      Method = SWAPSIGN;
    } else {
      Method = SWAPSIGN_DIVIDE;
    }
  } else if (Numerator == 1) {
    if (Denominator == 1) {
      Method = 0;
    } else {
      Method = DIVIDE;
    }
  } else {
    if (Denominator == 1) {
      Method = MULTIPLY;
    } else {
      Method = MULTIPLY_DIVIDE;
    }
  }
  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) {
    switch (Method) {
    case SWAPSIGN:
      y0 = -*(pay + i++) + yOff;
      break;
    case SWAPSIGN_DIVIDE:
      y0 = (U32)(-*(pay + i++) + yOff) / (U32)Denominator;
      break;
    case DIVIDE:
      y0 = (U32)(*(pay + i++) + yOff) / (U32)Denominator;
      break;
    case MULTIPLY:
      y0 = (U32)(*(pay + i++) + yOff) * (U32)Numerator;
      break;
    case MULTIPLY_DIVIDE:
      y0 = (U32)(*(pay + i++) + yOff) * (U32)Numerator / (U32)Denominator;
      break;
    default:
      y0 = *(pay + i++) + yOff;
    }
    /* Iterate */
    for (; i < NumPoints; i++) {
      /* Perform high level clipping in y */
      switch (Method) {
      case SWAPSIGN:
        y1 = -*(pay + i) + yOff;
        break;
      case SWAPSIGN_DIVIDE:
        y1 = (U32)(-*(pay + i) + yOff) / (U32)Denominator;
        break;
      case DIVIDE:
        y1 = (U32)(*(pay + i) + yOff) / (U32)Denominator;
        break;
      case MULTIPLY:
        y1 = (U32)(*(pay + i) + yOff) * (U32)Numerator;
        break;
      case MULTIPLY_DIVIDE:
        y1 = (U32)(*(pay + i) + yOff) * (U32)Numerator / (U32)Denominator;
        break;
      default:
        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;
    }
  }
}

/*********************************************************************
*
*       Public code
*
**********************************************************************
*/
/*********************************************************************
*
*       GUI_DrawGraphEx
*/  
void GUI_DrawGraphEx(I16 *pay, int NumPoints, int x0, int y0, int Numerator, int Denominator) {
  GUI_LOCK();
  #if (GUI_WINSUPPORT)
    WM_ADDORG(x0,y0);
    WM_ITERATE_START(NULL); {
  #endif
  _DrawGraph(pay, NumPoints, x0, y0, Numerator, Denominator);
  #if (GUI_WINSUPPORT)
    } WM_ITERATE_END();
  #endif
  GUI_UNLOCK();
}

/*************************** End of file ****************************/