54 lines
800 B
C
54 lines
800 B
C
/*
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*
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* Graphical routines for drawing a disk.
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*
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*/
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#include "u_mem.h"
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#include "gr.h"
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#include "grdef.h"
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#ifndef OGL
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int gr_disk(fix xc1,fix yc1,fix r1)
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{
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int p,x, y, xc, yc, r;
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r = f2i(r1);
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xc = f2i(xc1);
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yc = f2i(yc1);
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p=3-(r*2);
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x=0;
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y=r;
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// Big clip
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if ( (xc+r) < 0 ) return 1;
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if ( (xc-r) > GWIDTH ) return 1;
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if ( (yc+r) < 0 ) return 1;
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if ( (yc-r) > GHEIGHT ) return 1;
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while(x<y)
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{
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// Draw the first octant
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gr_scanline( xc-y, xc+y, yc-x );
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gr_scanline( xc-y, xc+y, yc+x );
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if (p<0)
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p=p+(x<<2)+6;
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else {
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// Draw the second octant
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gr_scanline( xc-x, xc+x, yc-y );
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gr_scanline( xc-x, xc+x, yc+y );
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p=p+((x-y)<<2)+10;
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y--;
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}
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x++;
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}
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if(x==y) {
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gr_scanline( xc-x, xc+x, yc-y );
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gr_scanline( xc-x, xc+x, yc+y );
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}
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return 0;
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}
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#endif
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