Ejemplo n.º 1
0
        public static Matrix4X4 GetXYInViewRotation(this WorldView world, Vector3 center)
        {
            var positions = new Vector3[]
            {
                center + new Vector3(1, 0, 0),
                center + new Vector3(0, 1, 0),
                center + new Vector3(-1, 0, 0),
                center + new Vector3(0, -1, 0),
            };

            double bestX  = double.NegativeInfinity;
            int    indexX = 0;

            // get the closest z on the bottom in view space
            for (int cornerIndex = 0; cornerIndex < 4; cornerIndex++)
            {
                Vector3 axisSide            = positions[cornerIndex];
                Vector3 axisSideScreenSpace = world.GetScreenSpace(axisSide);

                if (axisSideScreenSpace.X > bestX)
                {
                    indexX = cornerIndex;
                    bestX  = axisSideScreenSpace.X;
                }
            }

            var transform = Matrix4X4.Identity;

            switch (indexX)
            {
            case 0:
                // transform = Matrix4X4.CreateRotationZ(0);
                break;

            case 1:
                transform = Matrix4X4.CreateRotationZ(MathHelper.Tau / 4);
                break;

            case 2:
                transform = Matrix4X4.CreateRotationZ(-MathHelper.Tau / 2);
                break;

            case 3:
                transform = Matrix4X4.CreateRotationZ(MathHelper.Tau * 3 / 4);
                break;
            }

            return(transform);
        }