//----------------------------------------------------------------------------------------------------
MATRIX MatrixRotationAxis(const FLOAT3& axis, const FLOAT radians)
{
FLOAT3 axisN = axis.GetNormalization();
FLOAT sinAngle = sinf(radians);
FLOAT cosAngle = cosf(radians);
FLOAT rmCosAngle = 1 - cosAngle;
MATRIX result;
result(0, 0) = (FLOAT)((axisN.x * axisN.x) * rmCosAngle + cosAngle);
result(0, 1) = (FLOAT)((axisN.x * axisN.y) * rmCosAngle + (axisN.z * sinAngle));
result(0, 2) = (FLOAT)((axisN.x * axisN.z) * rmCosAngle - (axisN.y * sinAngle));
result(1, 0) = (FLOAT)((axisN.y * axisN.x) * rmCosAngle - (axisN.z * sinAngle));
result(1, 1) = (FLOAT)((axisN.y * axisN.y) * rmCosAngle + cosAngle);
result(1, 2) = (FLOAT)((axisN.y * axisN.z) * rmCosAngle + (axisN.x * sinAngle));
result(2, 0) = (FLOAT)((axisN.z * axisN.x) * rmCosAngle + (axisN.y * sinAngle));
result(2, 1) = (FLOAT)((axisN.z * axisN.y) * rmCosAngle - (axisN.x * sinAngle));
result(2, 2) = (FLOAT)((axisN.z * axisN.z) * rmCosAngle + cosAngle);
result(0, 3) = result(1, 3) = result(2, 3) = 0.0f;
result(3, 0) = result(3, 1) = result(3, 2) = 0.0f;
result(3, 3) = 1.0f;
return result;
}
//----------------------------------------------------------------------------------------------------
Quaternion QuaternionRotationAxis(const FLOAT3& _axis, const FLOAT _radians)
{
Quaternion result;
FLOAT3 axis = _axis.GetNormalization();
FLOAT ccc = cos(0.5f * _radians);
FLOAT sss = sin(0.5f * _radians);
result.t = ccc;
result.x = sss * axis.x;
result.y = sss * axis.y;
result.z = sss * axis.z;
return result;
}