The script of UE4 itself is the C + + language. Some problems of this method in practice

Can see, some complex, especially for me this UE4 and Android are not familiar with the people, only want to not, first of all, my needs are not complex, but in a model and reality overlap space using the motion tracking function of Project Tango to walk, rotate, etc., simply, I am now in the office environment, using 3D modeling to do an office-like model, long and wide to the right, so with the tracking of Project Tango, I can only look at the screen and know where I am in the office, whether there are obstacles in front, such as HTV The two of Vive's are like a small speaker to detect an active area.

Here by the way Gl_polygon, this is a special element, because its vertex number is indeterminate. The temporary small index it produces may no longer be small. But the magic is that it no longer requires a temporary index of the oneindexbufferptr type, but only a zeroindexbufferptr that barely occupies space.

The above scenario is a recommendation for a single-table approach to things management: In fact this does not apply to the management of things, but rather the practice of using MyBatis to manipulate data in bulk, in order to reduce the number of interactions with the database.

Now there is another scene, I want to the library/docu two tables (Student table, teacher table) at the same time insert a piece of data, either all succeed, or all failed, how to handle? In this case, it is obviously not possible to use the MyBatis batch operation method, in order to achieve this function, you can use spring's things management.

In the previous article, the DAO layer method is more of a database of the addition and deletion of the atomic operation, and the service layer of the method equivalent to the operation of these atoms to make a combination, here to operate Teacherdao, Studentdao in the Insert method, So create a Schoolservice interface:

We also mentioned in our last article that the operations such as reduce () are also aggregation operations, so why is there an accumulator this thing exists? Because the size of the synchronization mechanism provided by the RDD itself is too coarse, especially in the transformation operation, the variable state cannot be synchronized, and the accumulator can aggregate values that are not the same as the scope and granularity of the RDD itself, but it is a write-only variable that cannot read this value. The value of the accumulator can only be read in the driver using the value method.

The script of UE4 itself is the C + + language. Some problems of this method in practice

The script of UE4 itself is the C + + language. Some problems of this method in practice