You can not select more than 25 topics
			Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
		
		
		
		
		
			
		
			
				
					
					
						
							394 lines
						
					
					
						
							7.8 KiB
						
					
					
				
			
		
		
	
	
							394 lines
						
					
					
						
							7.8 KiB
						
					
					
				| /*
 | |
| 
 | |
|   u8g_ellipse.c
 | |
| 
 | |
|   Utility to draw empty and filled ellipses.
 | |
|   
 | |
|   Universal 8bit Graphics Library
 | |
|   
 | |
|   Copyright (c) 2011, bjthom@gmail.com
 | |
|   All rights reserved.
 | |
| 
 | |
|   Redistribution and use in source and binary forms, with or without modification, 
 | |
|   are permitted provided that the following conditions are met:
 | |
| 
 | |
|   * Redistributions of source code must retain the above copyright notice, this list 
 | |
|     of conditions and the following disclaimer.
 | |
|     
 | |
|   * Redistributions in binary form must reproduce the above copyright notice, this 
 | |
|     list of conditions and the following disclaimer in the documentation and/or other 
 | |
|     materials provided with the distribution.
 | |
| 
 | |
|   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
 | |
|   CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
 | |
|   INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
 | |
|   MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 | |
|   DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
 | |
|   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 | |
|   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
 | |
|   NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 | |
|   LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
 | |
|   CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
 | |
|   STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
 | |
|   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
 | |
|   ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
 | |
|   
 | |
|   Addition to the U8G Library as of 02/29/12
 | |
|   Adapted from Bresenham's Algorithm and the following websites:
 | |
| 	http://free.pages.at/easyfilter/bresenham.html
 | |
| 	http://homepage.smc.edu/kennedy_john/belipse.pdf
 | |
|   
 | |
| */
 | |
| 
 | |
| #include "u8g.h"
 | |
| 
 | |
| 
 | |
| #ifdef WORK_IN_PROGRESS
 | |
| 
 | |
| void u8g_DrawEllipseRect(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t x1, u8g_uint_t y1)
 | |
| {
 | |
| 	int a = abs(x1 - x0);
 | |
| 	int b = abs(y1 - y0);	//get diameters
 | |
| 	int b1 = b&1;
 | |
| 	long dx = 4*(1-a)*b*b;
 | |
| 	long dy = 4*(b1+1)*a*a;
 | |
| 	long err = dx+dy+b1*a*a;
 | |
| 	long e2;
 | |
| 	
 | |
| 	if (x0 > x1) { x0 = x1; x1 += a; }
 | |
| 	if (y0 > y1) { y0 = y1; } 
 | |
| 	y0 += (b+1)/2;
 | |
| 	y1 = y0-b1;
 | |
| 	a *= 8*a;
 | |
| 	b1 = 8*b*b;
 | |
| 	
 | |
| 	do {
 | |
| 		u8g_DrawPixel(u8g, x1, y0);
 | |
| 		u8g_DrawPixel(u8g, x0, y0);
 | |
| 		u8g_DrawPixel(u8g, x0, y1);
 | |
| 		u8g_DrawPixel(u8g, x1, y1);
 | |
| 		e2 = 2*err;
 | |
| 		if (e2 >= dx) {
 | |
| 			x0++;
 | |
| 			x1--;
 | |
| 			err += dx += b1;
 | |
| 		}
 | |
| 		if (e2 <= dy) {
 | |
| 			y0++;
 | |
| 			y1--;
 | |
| 			err += dy += a;
 | |
| 		}
 | |
| 	} while (x0 <= x1);
 | |
| 	
 | |
| 	while (y0-y1 < b) {
 | |
| 		u8g_DrawPixel(u8g, x0-1, y0);
 | |
| 		u8g_DrawPixel(u8g, x1+1, y0++);
 | |
| 		u8g_DrawPixel(u8g, x0-1, y1);
 | |
| 		u8g_DrawPixel(u8g, x1+1, y1--);
 | |
| 	}
 | |
| }
 | |
| 
 | |
| void u8g_DrawEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t xr, u8g_uint_t yr)
 | |
| {
 | |
| 	u8g_DrawPixel(u8g, x0, y0+yr);
 | |
| 	u8g_DrawPixel(u8g, x0, y0-yr);
 | |
| 	u8g_DrawPixel(u8g, x0+xr, y0);
 | |
| 	u8g_DrawPixel(u8g, x0-xr, y0);
 | |
| }
 | |
| 
 | |
| #endif
 | |
| 
 | |
| #if defined(U8G_16BIT)
 | |
| typedef  int32_t u8g_long_t;
 | |
| #else
 | |
| typedef  int16_t u8g_long_t;
 | |
| #endif
 | |
| 
 | |
| 
 | |
| /*
 | |
|   Source: 
 | |
|     ftp://pc.fk0.name/pub/books/programming/bezier-ellipse.pdf
 | |
|     Foley, Computer Graphics, p 90
 | |
| */
 | |
| static void u8g_draw_ellipse_section(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t x0, u8g_uint_t y0, uint8_t option) U8G_NOINLINE;
 | |
| static void u8g_draw_ellipse_section(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t x0, u8g_uint_t y0, uint8_t option)
 | |
| {
 | |
|     /* upper right */
 | |
|     if ( option & U8G_DRAW_UPPER_RIGHT )
 | |
|     {
 | |
|       u8g_DrawPixel(u8g, x0 + x, y0 - y);
 | |
|     }
 | |
|     
 | |
|     /* upper left */
 | |
|     if ( option & U8G_DRAW_UPPER_LEFT )
 | |
|     {
 | |
|       u8g_DrawPixel(u8g, x0 - x, y0 - y);
 | |
|     }
 | |
|     
 | |
|     /* lower right */
 | |
|     if ( option & U8G_DRAW_LOWER_RIGHT )
 | |
|     {
 | |
|       u8g_DrawPixel(u8g, x0 + x, y0 + y);
 | |
|     }
 | |
|     
 | |
|     /* lower left */
 | |
|     if ( option & U8G_DRAW_LOWER_LEFT )
 | |
|     {
 | |
|       u8g_DrawPixel(u8g, x0 - x, y0 + y);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void u8g_draw_ellipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t option)
 | |
| {
 | |
|   u8g_uint_t x, y;
 | |
|   u8g_long_t xchg, ychg;
 | |
|   u8g_long_t err;
 | |
|   u8g_long_t rxrx2;
 | |
|   u8g_long_t ryry2;
 | |
|   u8g_long_t stopx, stopy;
 | |
|   
 | |
|   rxrx2 = rx;
 | |
|   rxrx2 *= rx;
 | |
|   rxrx2 *= 2;
 | |
|   
 | |
|   ryry2 = ry;
 | |
|   ryry2 *= ry;
 | |
|   ryry2 *= 2;
 | |
|   
 | |
|   x = rx;
 | |
|   y = 0;
 | |
|   
 | |
|   xchg = 1;
 | |
|   xchg -= rx;
 | |
|   xchg -= rx;
 | |
|   xchg *= ry;
 | |
|   xchg *= ry;
 | |
|   
 | |
|   ychg = rx;
 | |
|   ychg *= rx;
 | |
|   
 | |
|   err = 0;
 | |
|   
 | |
|   stopx = ryry2;
 | |
|   stopx *= rx;
 | |
|   stopy = 0;
 | |
|   
 | |
|   while( stopx >= stopy )
 | |
|   {
 | |
|     u8g_draw_ellipse_section(u8g, x, y, x0, y0, option);
 | |
|     y++;
 | |
|     stopy += rxrx2;
 | |
|     err += ychg;
 | |
|     ychg += rxrx2;
 | |
|     if ( 2*err+xchg > 0 )
 | |
|     {
 | |
|       x--;
 | |
|       stopx -= ryry2;
 | |
|       err += xchg;
 | |
|       xchg += ryry2;      
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   x = 0;
 | |
|   y = ry;
 | |
|   
 | |
|   xchg = ry;
 | |
|   xchg *= ry;
 | |
|   
 | |
|   ychg = 1;
 | |
|   ychg -= ry;
 | |
|   ychg -= ry;
 | |
|   ychg *= rx;
 | |
|   ychg *= rx;
 | |
|   
 | |
|   err = 0;
 | |
|   
 | |
|   stopx = 0;
 | |
| 
 | |
|   stopy = rxrx2;
 | |
|   stopy *= ry;
 | |
|   
 | |
| 
 | |
|   while( stopx <= stopy )
 | |
|   {
 | |
|     u8g_draw_ellipse_section(u8g, x, y, x0, y0, option);
 | |
|     x++;
 | |
|     stopx += ryry2;
 | |
|     err += xchg;
 | |
|     xchg += ryry2;
 | |
|     if ( 2*err+ychg > 0 )
 | |
|     {
 | |
|       y--;
 | |
|       stopy -= rxrx2;
 | |
|       err += ychg;
 | |
|       ychg += rxrx2;
 | |
|     }
 | |
|   }
 | |
|   
 | |
| }
 | |
| 
 | |
| void u8g_DrawEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t option)
 | |
| {
 | |
|   /* check for bounding box */
 | |
|   {
 | |
|     u8g_uint_t rxp, rxp2;
 | |
|     u8g_uint_t ryp, ryp2;
 | |
|     
 | |
|     rxp = rx;
 | |
|     rxp++;
 | |
|     rxp2 = rxp;
 | |
|     rxp2 *= 2;
 | |
| 
 | |
|     ryp = ry;
 | |
|     ryp++;
 | |
|     ryp2 = ryp;
 | |
|     ryp2 *= 2;
 | |
|     
 | |
|     if ( u8g_IsBBXIntersection(u8g, x0-rxp, y0-ryp, rxp2, ryp2) == 0)
 | |
|       return;    
 | |
|   }
 | |
|   
 | |
|   u8g_draw_ellipse(u8g, x0, y0, rx, ry, option);
 | |
| }
 | |
| 
 | |
| static void u8g_draw_filled_ellipse_section(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t x0, u8g_uint_t y0, uint8_t option) U8G_NOINLINE;
 | |
| static void u8g_draw_filled_ellipse_section(u8g_t *u8g, u8g_uint_t x, u8g_uint_t y, u8g_uint_t x0, u8g_uint_t y0, uint8_t option)
 | |
| {
 | |
|     /* upper right */
 | |
|     if ( option & U8G_DRAW_UPPER_RIGHT )
 | |
|     {
 | |
|       u8g_DrawVLine(u8g, x0+x, y0-y, y+1);
 | |
|     }
 | |
|     
 | |
|     /* upper left */
 | |
|     if ( option & U8G_DRAW_UPPER_LEFT )
 | |
|     {
 | |
|       u8g_DrawVLine(u8g, x0-x, y0-y, y+1);
 | |
|     }
 | |
|     
 | |
|     /* lower right */
 | |
|     if ( option & U8G_DRAW_LOWER_RIGHT )
 | |
|     {
 | |
|       u8g_DrawVLine(u8g, x0+x, y0, y+1);
 | |
|     }
 | |
|     
 | |
|     /* lower left */
 | |
|     if ( option & U8G_DRAW_LOWER_LEFT )
 | |
|     {
 | |
|       u8g_DrawVLine(u8g, x0-x, y0, y+1);
 | |
|     }
 | |
| }
 | |
| 
 | |
| void u8g_draw_filled_ellipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t option)
 | |
| {
 | |
|   u8g_uint_t x, y;
 | |
|   u8g_long_t xchg, ychg;
 | |
|   u8g_long_t err;
 | |
|   u8g_long_t rxrx2;
 | |
|   u8g_long_t ryry2;
 | |
|   u8g_long_t stopx, stopy;
 | |
|   
 | |
|   rxrx2 = rx;
 | |
|   rxrx2 *= rx;
 | |
|   rxrx2 *= 2;
 | |
|   
 | |
|   ryry2 = ry;
 | |
|   ryry2 *= ry;
 | |
|   ryry2 *= 2;
 | |
|   
 | |
|   x = rx;
 | |
|   y = 0;
 | |
|   
 | |
|   xchg = 1;
 | |
|   xchg -= rx;
 | |
|   xchg -= rx;
 | |
|   xchg *= ry;
 | |
|   xchg *= ry;
 | |
|   
 | |
|   ychg = rx;
 | |
|   ychg *= rx;
 | |
|   
 | |
|   err = 0;
 | |
|   
 | |
|   stopx = ryry2;
 | |
|   stopx *= rx;
 | |
|   stopy = 0;
 | |
|   
 | |
|   while( stopx >= stopy )
 | |
|   {
 | |
|     u8g_draw_filled_ellipse_section(u8g, x, y, x0, y0, option);
 | |
|     y++;
 | |
|     stopy += rxrx2;
 | |
|     err += ychg;
 | |
|     ychg += rxrx2;
 | |
|     if ( 2*err+xchg > 0 )
 | |
|     {
 | |
|       x--;
 | |
|       stopx -= ryry2;
 | |
|       err += xchg;
 | |
|       xchg += ryry2;      
 | |
|     }
 | |
|   }
 | |
| 
 | |
|   x = 0;
 | |
|   y = ry;
 | |
|   
 | |
|   xchg = ry;
 | |
|   xchg *= ry;
 | |
|   
 | |
|   ychg = 1;
 | |
|   ychg -= ry;
 | |
|   ychg -= ry;
 | |
|   ychg *= rx;
 | |
|   ychg *= rx;
 | |
|   
 | |
|   err = 0;
 | |
|   
 | |
|   stopx = 0;
 | |
| 
 | |
|   stopy = rxrx2;
 | |
|   stopy *= ry;
 | |
|   
 | |
| 
 | |
|   while( stopx <= stopy )
 | |
|   {
 | |
|     u8g_draw_filled_ellipse_section(u8g, x, y, x0, y0, option);
 | |
|     x++;
 | |
|     stopx += ryry2;
 | |
|     err += xchg;
 | |
|     xchg += ryry2;
 | |
|     if ( 2*err+ychg > 0 )
 | |
|     {
 | |
|       y--;
 | |
|       stopy -= rxrx2;
 | |
|       err += ychg;
 | |
|       ychg += rxrx2;
 | |
|     }
 | |
|   }
 | |
|   
 | |
| }
 | |
| 
 | |
| void u8g_DrawFilledEllipse(u8g_t *u8g, u8g_uint_t x0, u8g_uint_t y0, u8g_uint_t rx, u8g_uint_t ry, uint8_t option)
 | |
| {
 | |
|   /* check for bounding box */
 | |
|   {
 | |
|     u8g_uint_t rxp, rxp2;
 | |
|     u8g_uint_t ryp, ryp2;
 | |
|     
 | |
|     rxp = rx;
 | |
|     rxp++;
 | |
|     rxp2 = rxp;
 | |
|     rxp2 *= 2;
 | |
| 
 | |
|     ryp = ry;
 | |
|     ryp++;
 | |
|     ryp2 = ryp;
 | |
|     ryp2 *= 2;
 | |
|     
 | |
|     if ( u8g_IsBBXIntersection(u8g, x0-rxp, y0-ryp, rxp2, ryp2) == 0)
 | |
|       return;    
 | |
|   }
 | |
|   
 | |
|   u8g_draw_filled_ellipse(u8g, x0, y0, rx, ry, option);
 | |
| }
 |