101 lines
5.4 KiB
C++
101 lines
5.4 KiB
C++
/*
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* Portions of this file are copyright Rebirth contributors and licensed as
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* described in COPYING.txt.
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* Portions of this file are copyright Parallax Software and licensed
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* according to the Parallax license below.
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* See COPYING.txt for license details.
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THE COMPUTER CODE CONTAINED HEREIN IS THE SOLE PROPERTY OF PARALLAX
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SOFTWARE CORPORATION ("PARALLAX"). PARALLAX, IN DISTRIBUTING THE CODE TO
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END-USERS, AND SUBJECT TO ALL OF THE TERMS AND CONDITIONS HEREIN, GRANTS A
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ROYALTY-FREE, PERPETUAL LICENSE TO SUCH END-USERS FOR USE BY SUCH END-USERS
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IN USING, DISPLAYING, AND CREATING DERIVATIVE WORKS THEREOF, SO LONG AS
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SUCH USE, DISPLAY OR CREATION IS FOR NON-COMMERCIAL, ROYALTY OR REVENUE
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FREE PURPOSES. IN NO EVENT SHALL THE END-USER USE THE COMPUTER CODE
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CONTAINED HEREIN FOR REVENUE-BEARING PURPOSES. THE END-USER UNDERSTANDS
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AND AGREES TO THE TERMS HEREIN AND ACCEPTS THE SAME BY USE OF THIS FILE.
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COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION. ALL RIGHTS RESERVED.
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*/
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/*
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*
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* Macros used for clipping
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*
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*/
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// sort two values
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#define SORT2(a,b) do { \
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using std::swap; \
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if((a) > (b)) swap(a,b); \
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} while(0)
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# define FIXSCALE(var,arg,num,den) ((var) = fixmuldiv((arg),(num),(den)))
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#define CLIPLINE(x1,y1,x2,y2,XMIN,YMIN,XMAX,YMAX,WHEN_OUTSIDE,WHEN_CLIPPED,MY_SCALE) do { \
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int temp; \
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if(y1 > y2) \
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{ \
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using std::swap; \
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swap(y1,y2); swap(x1,x2); } \
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if((y2 < YMIN) || (y1 > YMAX)) \
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{ WHEN_OUTSIDE; } \
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if(x1 < x2) { \
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if((x2 < XMIN) || (x1 > XMAX)) { \
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WHEN_OUTSIDE; \
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} \
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if(x1 < XMIN) { \
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MY_SCALE(temp,(y2 - y1),(XMIN - x1),(x2 - x1)); \
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if((y1 += temp) > YMAX) { WHEN_OUTSIDE; } \
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x1 = XMIN; \
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WHEN_CLIPPED; \
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} \
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if(x2 > XMAX) { \
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MY_SCALE(temp,(y2 - y1),(x2 - XMAX),(x2 - x1)); \
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if((y2 -= temp) < YMIN) { WHEN_OUTSIDE; } \
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x2 = XMAX; \
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WHEN_CLIPPED; \
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} \
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if(y1 < YMIN) { \
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MY_SCALE(temp,(x2 - x1),(YMIN - y1),(y2 - y1)); \
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x1 += temp; \
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y1 = YMIN; \
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WHEN_CLIPPED; \
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} \
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if(y2 > YMAX) { \
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MY_SCALE(temp,(x2 - x1),(y2 - YMAX),(y2 - y1)); \
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x2 -= temp; \
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y2 = YMAX; \
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WHEN_CLIPPED; \
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} \
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} \
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else { \
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if((x1 < XMIN) || (x2 > XMAX)) { \
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WHEN_OUTSIDE; \
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} \
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if(x1 > XMAX) { \
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MY_SCALE(temp,(y2 - y1),(x1 - XMAX),(x1 - x2)); \
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if((y1 += temp) > YMAX) { WHEN_OUTSIDE; } \
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x1 = XMAX; \
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WHEN_CLIPPED; \
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} \
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if(x2 < XMIN) { \
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MY_SCALE(temp,(y2 - y1),(XMIN - x2),(x1 - x2)); \
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if((y2 -= temp) < YMIN) { WHEN_OUTSIDE; } \
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x2 = XMIN; \
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WHEN_CLIPPED; \
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} \
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if(y1 < YMIN) { \
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MY_SCALE(temp,(x1 - x2),(YMIN - y1),(y2 - y1)); \
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x1 -= temp; \
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y1 = YMIN; \
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WHEN_CLIPPED; \
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} \
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if(y2 > YMAX) { \
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MY_SCALE(temp,(x1 - x2),(y2 - YMAX),(y2 - y1)); \
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x2 += temp; \
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y2 = YMAX; \
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WHEN_CLIPPED; \
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} \
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} \
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} while(0)
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