コード例 #1
0
        //////////////TRANSFORM_METHODS////////////////
        ///////////////////////////////////////////////
        /////////////INTERSECTION_METHODS//////////////

        public override GlPointR2[] getIntersection(GlLineR2 L)
        {
            if (L == null || L.pointOfLine.isNullPoint())
            {
                return new GlPointR2[] { }
            }
            ;

            if (GlPointR2.Equals(this.pointOfLine, L.pointOfLine))//already have a result
            {
                return new GlPointR2[] { new GlPointR2(L.pointOfLine) }
            }
            ;

            bool isL1Point = this.DirectVector.isNullVector();
            bool isL2Point = L.DirectVector.isNullVector();

            if (isL1Point && isL2Point)//same points were catched in previous step
            {
                return new GlPointR2[] { }
            }
            ;

            if (this.DirectVector.isNullVector() && L.isPointBelongs(this.pointOfLine))//line and a point
            {
                return new GlPointR2[] { new GlPointR2(this.pointOfLine) }
            }
            ;

            if (L.DirectVector.isNullVector() && this.isPointBelongs(L.pointOfLine))//line and a point
            {
                return new GlPointR2[] { new GlPointR2(L.pointOfLine) }
            }
            ;

            if (GlLineR2.Equals(this, L))//lines are identical
            {
                return new GlPointR2[] { new GlPointR2(this.pointOfLine), new GlPointR2(L.PointOfLine) }
            }
            ;

            if (GlVectorR2.isParallel(this.DirectVector, L.DirectVector))//lines are parallel
            {
                return new GlPointR2[] { }
            }
            ;

            if (L.DirectVector.deltaX == 0)//L2 is parallel to Y axis
            {
                return new GlPointR2[] { new GlPointR2(L.pointOfLine.X, this.DirectVector.deltaY * (L.pointOfLine.X - this.pointOfLine.X) / this.DirectVector.deltaX + this.pointOfLine.Y) }
            }
            ;

            if (this.DirectVector.deltaY == 0)//L1 is parallel to X axis
            {
                return new GlPointR2[] { new GlPointR2(L.DirectVector.deltaX * (this.pointOfLine.Y - L.pointOfLine.Y) / L.DirectVector.deltaY + L.pointOfLine.X, this.pointOfLine.Y) }
            }
            ;

            float v2RatYX = L.DirectVector.deltaY / L.DirectVector.deltaX;
            float v1RatXY = this.DirectVector.deltaX / this.DirectVector.deltaY;
            float yInter  = (v1RatXY * v2RatYX * this.pointOfLine.Y - v2RatYX * this.pointOfLine.X + v2RatYX * L.pointOfLine.X - L.pointOfLine.Y) / (v1RatXY * v2RatYX - 1);
            float xInter  = v1RatXY * (yInter - this.pointOfLine.Y) + this.pointOfLine.X;

            return(new GlPointR2[] { new GlPointR2(xInter, yInter) });//common situation
        }