public bool GetOverlaps(BoundingBox localSpaceBoundingBox, RawList<TriangleMeshConvexContactManifold.TriangleIndices> overlappedTriangles)
{
int width = heights.GetLength(0);
int minX = Math.Max((int)localSpaceBoundingBox.Min.X, 0);
int minY = Math.Max((int)localSpaceBoundingBox.Min.Z, 0);
int maxX = Math.Min((int)localSpaceBoundingBox.Max.X, width - 2);
int maxY = Math.Min((int)localSpaceBoundingBox.Max.Z, heights.GetLength(1) - 2);
for (int i = minX; i <= maxX; i++)
{
for (int j = minY; j <= maxY; j++)
{
//Before adding a triangle to the list, make sure the object isn't too high or low from the quad.
float highest, lowest;
float y1 = heights[i, j];
float y2 = heights[i + 1, j];
float y3 = heights[i, j + 1];
float y4 = heights[i + 1, j + 1];
highest = y1;
lowest = y1;
if (y2 > highest)
highest = y2;
else if (y2 < lowest)
lowest = y2;
if (y3 > highest)
highest = y3;
else if (y3 < lowest)
lowest = y3;
if (y4 > highest)
highest = y4;
else if (y4 < lowest)
lowest = y4;
if (localSpaceBoundingBox.Max.Y < lowest ||
localSpaceBoundingBox.Min.Y > highest)
continue;
//Now the local bounding box is very likely intersecting those of the triangles.
//Add the triangles to the list.
var indices = new TriangleMeshConvexContactManifold.TriangleIndices();
//v3 v4
//v1 v2
if (quadTriangleOrganization == QuadTriangleOrganization.BottomLeftUpperRight)
{
//v1 v2 v3
indices.A = i + j * width;
indices.B = i + 1 + j * width;
indices.C = i + (j + 1) * width;
overlappedTriangles.Add(indices);
//v2 v4 v3
indices.A = i + 1 + j * width;
indices.B = i + 1 + (j + 1) * width;
indices.C = i + (j + 1) * width;
overlappedTriangles.Add(indices);
}
else //Bottom right, Upper left
{
//v1 v2 v4
indices.A = i + j * width;
indices.B = i + 1 + j * width;
indices.C = i + 1 + (j + 1) * width;
overlappedTriangles.Add(indices);
//v1 v4 v3
indices.A = i + j * width;
indices.B = i + 1 + (j + 1) * width;
indices.C = i + (j + 1) * width;
overlappedTriangles.Add(indices);
}
}
}
return overlappedTriangles.Count > 0;
}
