bool CHitSquare::CheckHitLineSegmentLineSegment(Segment * seg1,Segment * seg2,D3DXVECTOR2* outPos)
{
D3DXVECTOR2 v = seg2->s - seg1->s;
float Crs_v1_v2 = D3DXVec2Cross( &seg1->v, &seg2->v );
if ( Crs_v1_v2 == 0.0f ) {
// 平行状態
return false;
}
float Crs_v_v1 = D3DXVec2Cross( &v, &seg1->v );
float Crs_v_v2 = D3DXVec2Cross( &v, &seg2->v );
float t1 = Crs_v_v2 / Crs_v1_v2;
float t2 = Crs_v_v1 / Crs_v1_v2;
const float eps = 0.00001f;
if ( t1 + eps < 0 || t1 - eps > 1 || t2 + eps < 0 || t2 - eps > 1 ) {
// 交差していない
return false;
}
if( outPos )
*outPos = seg1->s + seg1->v * t1;
return true;
}
//直線交差判定
//線分１、線分２、交点
bool IsHitByLine(SEGMENT segment1, SEGMENT segment2, D3DXVECTOR2* point)
{
bool isHit = false;
D3DXVECTOR2 vec = segment2.vec2StartPoint - segment1.vec2StartPoint;
float CrossV1_V2 = D3DXVec2Cross(segment1.vec2Direct, segment2.vec2Direct);
//平行
if(CrossV1_V2 == 0.0f)
{
return false;
}
float CrossV_V1 = D3DXVec2Cross(vec, segment1.vec2Direct);
float CrossV_V2 = D3DXVec2Cross(vec, segment2.vec2Direct);
float t1 = CrossV_V2 / CrossV1_V2;
float t2 = CrossV_V1 / CrossV1_V2;
const float eps = 0.00001f;
if((t1+ eps < 0.0f || t1- eps >1.0f) || (t2 + eps < 0.0f || t2 - eps>1.0f))
{
return false;
}
isHit = true;
*point = segment1.vec2StartPoint + segment1.vec2Direct * t1;
return isHit;
}
bool CHitSquare::CheckHitCircleLineSegment(Circle * pcircle,Segment * seg)
{
Segment segbuf,segbuf2;
segbuf.s = seg->s;
segbuf.v = pcircle->center - seg->s;
segbuf2.s = seg->s + seg->v;
segbuf2.v = segbuf.v - seg->v;
float lenge = D3DXVec2Cross(&seg->v,&segbuf.v)/D3DXVec2Length(&seg->v);
if(D3DXVec2Length(&seg->v) == 0)
lenge = D3DXVec2Length(&(segbuf.v));
if(lenge < 0)
lenge = -lenge;
if(pcircle->halfdiameter < lenge)
return false;
if(D3DXVec2Dot(&segbuf.v,&seg->v)*D3DXVec2Dot(&segbuf2.v,&seg->v) <= 0)
return true;
else
if(pcircle->halfdiameter > D3DXVec2Length(&segbuf.v )||pcircle->halfdiameter > D3DXVec2Length(&segbuf2.v ))
return true;
return false;
}
