43 lines
905 B
Plaintext
43 lines
905 B
Plaintext
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struct Line3
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{
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vec3 start;
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vec3 end;
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};
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vec3 Line3_getAt( inout Line3 line, float t )
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{
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return line.start + ( line.end - line.start ) * t;
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}
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float Line3_closestParameterToPoint( inout Line3 line, vec3 point )
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{
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vec3 startP = point - line.start;
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vec3 startEnd = line.end - line.start;
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float startEnd2 = dot( startEnd, startEnd );
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float startEnd_startP = dot( startEnd, startP );
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if ( startEnd2 == 0.0 )
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{
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return 0.5;
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}
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float t = startEnd_startP / startEnd2;
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return t;
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}
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vec3 Line3_closestPointToPoint( inout Line3 line, vec3 point )
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{
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float parameter = Line3_closestParameterToPoint( line, point );
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return Line3_getAt( line, parameter );
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}
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float Line3_getDistance( inout Line3 line, vec3 point )
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{
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float parameter = clamp( Line3_closestParameterToPoint( line, point ), 0, 1 );
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vec3 p = Line3_getAt( line, parameter );
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return length( point - p );
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}
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