/// <inheritDoc/>
public override int IntersectsSegment(float xA, float yA, float xB, float yB,
Point intersectionPointA = null,
Point intersectionPointB = null,
Point normalRadians = null)
{
var widthH = this.width * 0.5f;
var heightH = this.height * 0.5f;
var intersectionCount = RectangleBoundingBoxData.RectangleIntersectsSegment
(
xA, yA, xB, yB,
-widthH, -heightH, widthH, heightH,
intersectionPointA, intersectionPointB, normalRadians
);
return(intersectionCount);
}
/// <inheritDoc/>
public override int IntersectsSegment(float xA, float yA, float xB, float yB,
Point intersectionPointA = null,
Point intersectionPointB = null,
Point normalRadians = null)
{
var intersectionCount = 0;
if (RectangleBoundingBoxData.RectangleIntersectsSegment(xA, yA, xB, yB, this.x, this.y, this.width, this.height, null, null, null) != 0)
{
intersectionCount = PolygonBoundingBoxData.PolygonIntersectsSegment
(
xA, yA, xB, yB,
this.vertices,
intersectionPointA, intersectionPointB, normalRadians
);
}
return(intersectionCount);
}
/// <private/>
public static int RectangleIntersectsSegment(float xA, float yA, float xB, float yB,
float xMin, float yMin, float xMax, float yMax,
Point intersectionPointA = null,
Point intersectionPointB = null,
Point normalRadians = null)
{
var inSideA = xA > xMin && xA <xMax && yA> yMin && yA < yMax;
var inSideB = xB > xMin && xB <xMax && yB> yMin && yB < yMax;
if (inSideA && inSideB)
{
return(-1);
}
var intersectionCount = 0;
var outcode0 = RectangleBoundingBoxData._ComputeOutCode(xA, yA, xMin, yMin, xMax, yMax);
var outcode1 = RectangleBoundingBoxData._ComputeOutCode(xB, yB, xMin, yMin, xMax, yMax);
while (true)
{
if ((outcode0 | outcode1) == 0)
{ // Bitwise OR is 0. Trivially accept and get out of loop
intersectionCount = 2;
break;
}
else if ((outcode0 & outcode1) != 0)
{ // Bitwise AND is not 0. Trivially reject and get out of loop
break;
}
// failed both tests, so calculate the line segment to clip
// from an outside point to an intersection with clip edge
var x = 0.0f;
var y = 0.0f;
var normalRadian = 0.0f;
// At least one endpoint is outside the clip rectangle; pick it.
var outcodeOut = outcode0 != 0 ? outcode0 : outcode1;
// Now find the intersection point;
if ((outcodeOut & (int)OutCode.Top) != 0)
{ // point is above the clip rectangle
x = xA + (xB - xA) * (yMin - yA) / (yB - yA);
y = yMin;
if (normalRadians != null)
{
normalRadian = -(float)Math.PI * 0.5f;
}
}
else if ((outcodeOut & (int)OutCode.Bottom) != 0)
{ // point is below the clip rectangle
x = xA + (xB - xA) * (yMax - yA) / (yB - yA);
y = yMax;
if (normalRadians != null)
{
normalRadian = (float)Math.PI * 0.5f;
}
}
else if ((outcodeOut & (int)OutCode.Right) != 0)
{ // point is to the right of clip rectangle
y = yA + (yB - yA) * (xMax - xA) / (xB - xA);
x = xMax;
if (normalRadians != null)
{
normalRadian = 0;
}
}
else if ((outcodeOut & (int)OutCode.Left) != 0)
{ // point is to the left of clip rectangle
y = yA + (yB - yA) * (xMin - xA) / (xB - xA);
x = xMin;
if (normalRadians != null)
{
normalRadian = (float)Math.PI;
}
}
// Now we move outside point to intersection point to clip
// and get ready for next pass.
if (outcodeOut == outcode0)
{
xA = x;
yA = y;
outcode0 = RectangleBoundingBoxData._ComputeOutCode(xA, yA, xMin, yMin, xMax, yMax);
if (normalRadians != null)
{
normalRadians.x = normalRadian;
}
}
else
{
xB = x;
yB = y;
outcode1 = RectangleBoundingBoxData._ComputeOutCode(xB, yB, xMin, yMin, xMax, yMax);
if (normalRadians != null)
{
normalRadians.y = normalRadian;
}
}
}
if (intersectionCount > 0)
{
if (inSideA)
{
intersectionCount = 2; // 10
if (intersectionPointA != null)
{
intersectionPointA.x = xB;
intersectionPointA.y = yB;
}
if (intersectionPointB != null)
{
intersectionPointB.x = xB;
intersectionPointB.y = xB;
}
if (normalRadians != null)
{
normalRadians.x = normalRadians.y + (float)Math.PI;
}
}
else if (inSideB)
{
intersectionCount = 1; // 01
if (intersectionPointA != null)
{
intersectionPointA.x = xA;
intersectionPointA.y = yA;
}
if (intersectionPointB != null)
{
intersectionPointB.x = xA;
intersectionPointB.y = yA;
}
if (normalRadians != null)
{
normalRadians.y = normalRadians.x + (float)Math.PI;
}
}
else
{
intersectionCount = 3; // 11
if (intersectionPointA != null)
{
intersectionPointA.x = xA;
intersectionPointA.y = yA;
}
if (intersectionPointB != null)
{
intersectionPointB.x = xB;
intersectionPointB.y = yB;
}
}
}
return(intersectionCount);
}