1 /* $Id: clip.h,v 1.4 2004-08-28 23:17:45 schaffner Exp $ */
3 THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
4 SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
5 END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
6 ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
7 IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
8 SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
9 FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
10 CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
11 AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
12 COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
16 * Macros used for clipping
21 /*#define MIN(a,b) (((a) < (b)) ? (a) : (b))
22 #define MAX(a,b) (((a) > (b)) ? (a) : (b))
24 #define IABS(x) (((x) < 0) ? -(x) : (x))
26 #define EXCHG(a,b) do { \
33 #define SORT2(a,b) do { \
34 if((a) > (b)) EXCHG(a,b); \
37 # define SCALE(var,arg,num,den) \
38 ((var) = ((arg) * (num)) / (den))
40 # define USCALE(var,arg,num,den) \
41 ((var) = ((unsigned)(arg) * (unsigned)(num)) / (unsigned)(den))
43 # define FSCALE(var,arg,num,den) ((var) = fixmuldiv((arg),(num),(den)))
45 #define CLIPDOT(xx,yy,WHEN_OUTSIDE,WHEN_CLIPPED) { \
46 if((xx > XMAX) || (xx < XMIN)) { WHEN_OUTSIDE; } \
47 if((yy > YMAX) || (yy < YMIN)) { WHEN_OUTSIDE; } \
50 #define CLIPHLINE(x1,x2,yy,WHEN_OUTSIDE,WHEN_CLIPPED) { \
51 if(x1 > x2) EXCHG(x1,x2); \
52 if((x1 > XMAX) || (x2 < XMIN)) { WHEN_OUTSIDE; } \
53 if((yy > YMAX) || (yy < YMIN)) { WHEN_OUTSIDE; } \
54 if(x1 < XMIN) { x1 = XMIN; WHEN_CLIPPED; } \
55 if(x2 > XMAX) { x2 = XMAX; WHEN_CLIPPED; } \
58 #define CLIPVLINE(xx,y1,y2,WHEN_OUTSIDE,WHEN_CLIPPED) { \
59 if(y1 > y2) EXCHG(y1,y2); \
60 if((xx > XMAX) || (xx < XMIN)) { WHEN_OUTSIDE; } \
61 if((y1 > YMAX) || (y2 < YMIN)) { WHEN_OUTSIDE; } \
62 if(y1 < YMIN) { y1 = YMIN; WHEN_CLIPPED; } \
63 if(y2 > YMAX) { y2 = YMAX; WHEN_CLIPPED; } \
66 #define CLIPBOX(x1,y1,x2,y2,WHEN_OUTSIDE,WHEN_CLIPPED) { \
67 if(x1 > x2) EXCHG(x1,x2); \
68 if(y1 > y2) EXCHG(y1,y2); \
69 if((x1 > XMAX) || (x2 < 0)) { WHEN_OUTSIDE; } \
70 if((y1 > YMAX) || (y2 < 0)) { WHEN_OUTSIDE; } \
71 if(x1 < 0) { x1 = 0; WHEN_CLIPPED; } \
72 if(y1 < 0) { y1 = 0; WHEN_CLIPPED; } \
73 if(x2 > XMAX) { x2 = XMAX; WHEN_CLIPPED; } \
74 if(y2 > YMAX) { y2 = YMAX; WHEN_CLIPPED; } \
77 #define CLIPLINE(x1,y1,x2,y2,XMIN,YMIN,XMAX,YMAX,WHEN_OUTSIDE,WHEN_CLIPPED,MY_SCALE) do { \
80 { EXCHG(y1,y2); EXCHG(x1,x2); } \
81 if((y2 < YMIN) || (y1 > YMAX)) \
84 if((x2 < XMIN) || (x1 > XMAX)) { \
88 MY_SCALE(temp,(y2 - y1),(XMIN - x1),(x2 - x1)); \
89 if((y1 += temp) > YMAX) { WHEN_OUTSIDE; } \
94 MY_SCALE(temp,(y2 - y1),(x2 - XMAX),(x2 - x1)); \
95 if((y2 -= temp) < YMIN) { WHEN_OUTSIDE; } \
100 MY_SCALE(temp,(x2 - x1),(YMIN - y1),(y2 - y1)); \
106 MY_SCALE(temp,(x2 - x1),(y2 - YMAX),(y2 - y1)); \
113 if((x1 < XMIN) || (x2 > XMAX)) { \
117 MY_SCALE(temp,(y2 - y1),(x1 - XMAX),(x1 - x2)); \
118 if((y1 += temp) > YMAX) { WHEN_OUTSIDE; } \
123 MY_SCALE(temp,(y2 - y1),(XMIN - x2),(x1 - x2)); \
124 if((y2 -= temp) < YMIN) { WHEN_OUTSIDE; } \
129 MY_SCALE(temp,(x1 - x2),(YMIN - y1),(y2 - y1)); \
135 MY_SCALE(temp,(x1 - x2),(y2 - YMAX),(y2 - y1)); \