Пример #1
0
        static public VFXExpression SafeNormalize(VFXExpression v)
        {
            var sqrDist   = Dot(v, v);
            var condition = new VFXExpressionCondition(VFXValueType.Float, VFXCondition.Less, sqrDist, VFXOperatorUtility.EpsilonSqrExpression[VFXValueType.Float]);

            return(new VFXExpressionBranch(condition, VFXOperatorUtility.ZeroExpression[v.valueType], Normalize(v)));
        }
Пример #2
0
        static public VFXExpression ApplyAddressingMode(VFXExpression index, VFXExpression count, SequentialAddressingMode mode)
        {
            VFXExpression r = null;

            if (mode == SequentialAddressingMode.Wrap)
            {
                r = Modulo(index, count);
            }
            else if (mode == SequentialAddressingMode.Clamp)
            {
                var countMinusOne = count - OneExpression[VFXValueType.Uint32];
                r = new VFXExpressionMin(index, countMinusOne);
            }
            else if (mode == SequentialAddressingMode.Mirror)
            {
                var two   = TwoExpression[VFXValueType.Uint32];
                var cycle = count * two - two;
                cycle = new VFXExpressionMax(cycle, OneExpression[VFXValueType.Uint32]);
                var modulo = Modulo(index, cycle);
                //var compare = new VFXExpressionCondition(VFXCondition.Less, new VFXExpressionCastUintToFloat(modulo), new VFXExpressionCastUintToFloat(count)); <= Use this line for 7.x.x/8.x.x/9.x.x backport
                var compare = new VFXExpressionCondition(VFXValueType.Uint32, VFXCondition.Less, modulo, count);
                r = new VFXExpressionBranch(compare, modulo, cycle - modulo);
            }
            return(r);
        }
Пример #3
0
        static public VFXExpression IsTRSMatrixZeroScaled(VFXExpression matrix)
        {
            var i = new VFXExpressionMatrixToVector3s(matrix, VFXValue.Constant(0));
            var j = new VFXExpressionMatrixToVector3s(matrix, VFXValue.Constant(1));
            var k = new VFXExpressionMatrixToVector3s(matrix, VFXValue.Constant(2));

            var sqrLengthI = Dot(i, i);
            var sqrLengthJ = Dot(j, j);
            var sqrLengthK = Dot(k, k);

            var epsilon = EpsilonSqrExpression[VFXValueType.Float];

            var compareI = new VFXExpressionCondition(VFXValueType.Float, VFXCondition.Less, sqrLengthI, epsilon);
            var compareJ = new VFXExpressionCondition(VFXValueType.Float, VFXCondition.Less, sqrLengthJ, epsilon);
            var compareK = new VFXExpressionCondition(VFXValueType.Float, VFXCondition.Less, sqrLengthK, epsilon);

            var condition = new VFXExpressionLogicalOr(compareI, new VFXExpressionLogicalOr(compareJ, compareK));

            return(condition);
        }