Fix SphereCast() with mesh shapes.

[and3md]

Hello,

I tried to use SphereCast() but it sometimes not works for me. I found the problem is in function SphereCastTriangle(). We have here code:

   if t<0.0 then begin
    result:=false;
    exit;
   end else begin
    Time:=-t;
    aU:=U;
    aV:=V;
    result:=true;
    exit;
   end;

But in function that call it (TKraftShapeMesh.SphereCast()) there is a condition (Time>=0.0):

       if SphereCastTriangle(Origin,
                             Radius,
                             Direction,
                             fMesh.fVertices[Triangle^.Vertices[DoubleSidedTriangleVertexOrderIndices[SidePass,0]]],
                             fMesh.fVertices[Triangle^.Vertices[DoubleSidedTriangleVertexOrderIndices[SidePass,1]]],
                             fMesh.fVertices[Triangle^.Vertices[DoubleSidedTriangleVertexOrderIndices[SidePass,2]]],
                             Time,
                             u,
                             v) then begin
        p:=Vector3Add(Origin,Vector3ScalarMul(Direction,Time));
        if ((Time>=0.0) and (Time<=SphereCastData.MaxTime)) and (First or (Time<Nearest)) then
        begin

So when t is greater than 0 it changes it sign and always is negative. My fix is to change that line to:

Time:=t;

After that SphereCast() works perfectly. My test case project is CGE simple game located in examples/physics/physics_3d_shooter in physics_walk_navigation branch commit 6fea532ae3550102bf3b6916c8a489a0022fe2ba.

[BeRo1985]

It should also be fixed with https://github.com/BeRo1985/kraft/commit/8e4c714960e6c79e8d5bb1267b42aab4b0719d66 now. :-)

[and3md]

Thanks :)