/***********************************************************************************************************                                                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        : GUIARCFloat.CPurpose     : Draw Arc routines based on floating point----------------------------------------------------------------------Version-Date---Author-Explanation----------------------------------------------------------------------2.00.00 000325 RS     First release of the new algorithm----------------------------------------------------------------------Known problems or limitations with current version----------------------------------------------------------------------None.----------------------------------------------------------------------Open issues----------------------------------------------------------------------None---------------------------END-OF-HEADER------------------------------*/#include <stddef.h>           /* needed for definition of NULL */#include <math.h>#include "GUI_Private.h"static void CalcX(int*px, int y, U32 r2) {  int x =*px;  U32 y2 = (U32)y*(U32)y;  U32 r2y2 = r2-y2;  U32 x2;  if (y2>=r2) {    *px=0;		return;	}  /* x2 = r2-y2 */  do {    x++;    x2 =(U32)x*(U32)x;	} while (x2 < r2y2);	*px = x-1;}static float CalcInterSectLin(float y, float y0, float y1, float x0, float x1) {  if (y1==y0) {	  return y0;	} else {    float Slope = (x1-x0)/(y1-y0);   return (y-y0)*Slope+x0;	}}static void _DrawArc(int x0, int y0, int rx, int ry, int Angle0, int Angle1, int xMul, int yMul) {  float afx[4];  float afy[4];	float ri = rx-(GUI_Context.PenSize+1.5)/2;	float ro = rx+(GUI_Context.PenSize+1.5)/2;  float fAngle0 = Angle0*3.1415926/180;  float fAngle1 = Angle1*3.1415926/180;  float sin0 = sin(fAngle0);   float sin1 = sin(fAngle1);   float cos0 = cos(fAngle0);   float cos1 = cos(fAngle1);   U32   ri2 = ri*ri;  U32   ro2 = ro*ro;	int y, yMax, yMin;	afy[0] = ri*sin0;	afy[1] = ro*sin0;	afy[2] = ri*sin1;	afy[3] = ro*sin1;	afx[0] = ri*cos0;	afx[1] = ro*cos0;	afx[2] = ri*cos1;	afx[3] = ro*cos1;	yMin = ceil(afy[0]);  yMax = floor(afy[3]);  /* Use Clipping rect to reduce calculation (if possible) */  if (GUI_Context.pClipRect_HL) {    if (yMul ==1) {      if (yMax > (GUI_Context.pClipRect_HL->y1 -y0))        yMax = (GUI_Context.pClipRect_HL->y1 -y0);      if (yMin < (GUI_Context.pClipRect_HL->y0 -y0))        yMin = (GUI_Context.pClipRect_HL->y0 -y0);    }    if (yMul == -1) {      if (yMin > (GUI_Context.pClipRect_HL->y1 -y0))        yMin = (GUI_Context.pClipRect_HL->y1 -y0);      if (yMax < (GUI_Context.pClipRect_HL->y0 -y0))        yMax = (GUI_Context.pClipRect_HL->y0 -y0);    }  }  /* Start drawing lines ... */  {  int xMinDisp, xMaxDisp, xMin=0,xMax=0;    for (y=yMax; y>=yMin; y--) {      CalcX(&xMin, y, ri2);      CalcX(&xMax, y, ro2);      if ((float)y< afy[1]) {        xMaxDisp = CalcInterSectLin(y,afy[0], afy[1], afx[0], afx[1]);			} else {        xMaxDisp = xMax;						}      if ((float)y > afy[2]) {        xMinDisp = CalcInterSectLin(y,afy[2], afy[3], afx[2], afx[3]);			} else {        xMinDisp = xMin;						}      if (xMul>0)        LCD_HL_DrawHLine(xMinDisp+x0, yMul*y+y0, xMaxDisp+x0);      else        LCD_HL_DrawHLine(-xMaxDisp+x0, yMul*y+y0, -xMinDisp+x0);    }	}#if 0  /* Test code */{  int i;  GUI_SetColor( GUI_WHITE ); 	for (i=0; i<4; i++)    LCD_HL_DrawPixel(afx[i]+x0, afy[i]+y0);}#endif  GUI_USE_PARA(ry);}void GL_DrawArc (int x0, int y0, int rx, int ry, int a0, int a1) {  int aEnd;  a0+=360;	a1+=360;	while (a0>=360) {    a0 -= 360;    a1 -= 360;	}/* Do first quadrant 0-90 degree */DoFirst:  if (a1<=0)	  return;	if (a0<90) {    if (a0<0)		  a0=0;    aEnd = (a1<90) ? a1 : 90;    _DrawArc(x0,y0,rx,ry,a0,aEnd, 1, -1);	}  a1-=90;	a0-=90;/* Do second quadrant 90-180 degree */  if (a1<=0)	  return;	if (a0<90) {    if (a0<0)		  a0=0;    aEnd = (a1<90) ? a1 : 90;    _DrawArc(x0,y0,rx,ry,90-aEnd, 90-a0,-1,-1);	}  a1-=90;	a0-=90;/* Do third quadrant 180-270 degree */  if (a1<=0)	  return;	if (a0<90) {    if (a0<0)		  a0=0;    aEnd = (a1<90) ? a1 : 90;    _DrawArc(x0,y0,rx,ry,a0,aEnd, -1, 1);	}  a1-=90;	a0-=90;/* Do last quadrant 270-360 degree */  if (a1<=0)	  return;	if (a0<90) {    if (a0<0)		  a0=0;    aEnd = (a1<90) ? a1 : 90;    _DrawArc(x0,y0,rx,ry,90-aEnd, 90-a0,1,1);	}  a1-=90;	a0-=90;goto DoFirst;}void GUI_DrawArc (int x0, int y0, int rx, int ry, int a0, int a1) {  GUI_LOCK();  #if (GUI_WINSUPPORT)    WM_ADDORG(x0,y0);    WM_ITERATE_START(NULL) {  #endif  GL_DrawArc( x0, y0, rx, ry, a0, a1);  #if (GUI_WINSUPPORT)    } WM_ITERATE_END();  #endif  GUI_UNLOCK();}