public static Vector2 CalculateOrigin(Body body)
{
Vector2 origin = Vector2.Zero;
if (body != null)
{
Vector2 leftBound = new Vector2(float.MaxValue);
Transform trans;
body.GetTransform(out trans);
for (int i = 0; i < body.FixtureList.Count; ++i)
{
for (int j = 0; j < body.FixtureList[i].Shape.ChildCount; ++j)
{
AABB bounds;
body.FixtureList[i].Shape.ComputeAABB(out bounds, ref trans, j);
Vector2.Min(ref leftBound, ref bounds.LowerBound, out leftBound);
}
}
// calculate body offset from its center and add a 1 pixel border
// because we generate the textures a little bigger than the actual body's fixtures
origin = ConvertUnits.ToDisplayUnits(body.Position - leftBound) + new Vector2(1f);
}
return origin;
}
public void ScaleToBody(Body body)
{
Transform t;
body.GetTransform(out t);
AABB aabb;
aabb.LowerBound = new Vector2(Settings.MaxFloat, Settings.MaxFloat);
aabb.UpperBound = new Vector2(-Settings.MaxFloat, -Settings.MaxFloat);
AABB tempAABB;
int fixtureCount = body.FixtureList.Count;
for (int i = 0; i < fixtureCount; ++i)
{
body.FixtureList[i].Shape.ComputeAABB(out tempAABB, ref t, 0);
aabb.Combine(ref tempAABB);
}
Vector2 scale = new Vector2(
ConvertUnits.ToDisplayUnits(aabb.Width) / sourceRect.Width,
ConvertUnits.ToDisplayUnits(aabb.Height) / sourceRect.Height
);
this.scale = scale;
}
/// <summary>
/// Cast a ray against this Shape.
/// </summary>
/// <param name="output">The ray-cast results.</param>
/// <param name="input">The ray-cast input parameters.</param>
/// <param name="childIndex">Index of the child.</param>
/// <returns></returns>
public bool RayCast(out RayCastOutput output, ref RayCastInput input, int childIndex)
{
Transform xf;
Body.GetTransform(out xf);
return(Shape.RayCast(out output, ref input, ref xf, childIndex));
}
/// <summary>
/// Test a point for containment in this fixture.
/// </summary>
/// <param name="point">A point in world coordinates.</param>
/// <returns></returns>
public bool TestPoint(ref Vector2 point)
{
Transform xf;
Body.GetTransform(out xf);
return(Shape.TestPoint(ref xf, ref point));
}
public static AABB GetAABBFromBody(Body body)
{
Transform t;
body.GetTransform(out t);
AABB aabb;
aabb.LowerBound = new Vector2(Settings.MaxFloat, Settings.MaxFloat);
aabb.UpperBound = new Vector2(-Settings.MaxFloat, -Settings.MaxFloat);
AABB tempAABB;
int fixtureCount = body.FixtureList.Count;
for (int i = 0; i < fixtureCount; ++i)
{
body.FixtureList[i].Shape.ComputeAABB(out tempAABB, ref t, 0);
aabb.Combine(ref tempAABB);
}
return aabb;
}
/// <summary>
/// Draws a single body
/// </summary>
/// <param name="body">the body to draw</param>
public void DrawBody(Body body)
{
Transform xf;
body.GetTransform(out xf);
foreach (Fixture f in body.FixtureList)
{
PolygonShape poly = (PolygonShape)f.Shape;
int vertexCount = poly.Vertices.Count;
if (vertexCount > MAX_VERTICES)
throw new Exception("Num vertices in polygon exceeds maximum number allowed");
for (int i = 0; i < vertexCount; i++)
tempVertices[i] = MathUtils.Multiply(ref xf, poly.Vertices[i]);
DrawPolygon(tempVertices, vertexCount, Color.SaddleBrown);
}
}