1 00:00:04,470 --> 00:00:05,550 ‫Hello and welcome. 2 00:00:05,550 --> 00:00:09,960 ‫In this lecture, we're going to be learning about comments, these things in Green and Visual Studio 3 00:00:09,960 --> 00:00:17,550 ‫code and how we can use them to write pseudo code to essentially be a note to ourselves on how we want 4 00:00:17,550 --> 00:00:18,930 ‫to implement something. 5 00:00:18,930 --> 00:00:21,420 ‫Let's dive in and learn about these concepts. 6 00:00:21,960 --> 00:00:24,650 ‫So what is pseudocode? 7 00:00:24,660 --> 00:00:25,650 ‫Pseudocode? 8 00:00:26,250 --> 00:00:32,520 ‫This is the dictionary definition is a plain language description of the steps that we're going to be 9 00:00:32,520 --> 00:00:33,660 ‫using in an algorithm. 10 00:00:33,660 --> 00:00:41,040 ‫So I want to write a plain language description of what we're planning to do to make this moving platform 11 00:00:41,040 --> 00:00:43,320 ‫go backwards and forwards. 12 00:00:43,590 --> 00:00:49,200 ‫Now, to do that, I could write out on a piece of paper, but I can actually write it into my code 13 00:00:49,200 --> 00:00:51,930 ‫without having to worry about making sure it's correct. 14 00:00:51,930 --> 00:00:55,230 ‫C++ and that is the whole point of pseudocode. 15 00:00:55,230 --> 00:01:00,600 ‫But to do that, we need to know one more piece of the puzzle, which is what is a comment? 16 00:01:00,600 --> 00:01:04,680 ‫A comment is code that is ignored by the compiler. 17 00:01:04,680 --> 00:01:11,070 ‫So it's a way of writing into our text file stuff for humans to read that the compiler will then ignore. 18 00:01:11,070 --> 00:01:13,320 ‫And we can just use that to write pseudocode. 19 00:01:13,320 --> 00:01:19,590 ‫We can use it to write notes to each other as programmers and to clarify what it is we're trying to 20 00:01:19,590 --> 00:01:21,210 ‫do in a piece of code. 21 00:01:21,210 --> 00:01:24,660 ‫So let's have a look at doing this over in the moving platform. 22 00:01:24,660 --> 00:01:26,940 ‫Keep in tick. 23 00:01:26,940 --> 00:01:32,910 ‫Now a comment is basically any line that starts with a double forward slash. 24 00:01:32,910 --> 00:01:38,280 ‫You can see that in Visual Studio code, this automatically gets coloured in in green and we can see 25 00:01:38,280 --> 00:01:45,780 ‫examples of these green lines elsewhere in the C++ file, you can see it says fill out a copyright notice. 26 00:01:45,780 --> 00:01:51,300 ‫It says sets default values called well, the game starts or when spawn called every frame. 27 00:01:51,300 --> 00:01:56,430 ‫So actually these comments are already helping us understand what's going on in this C++ file. 28 00:01:56,430 --> 00:02:01,470 ‫And now we understand that these lines have no particular meaning to the compiler. 29 00:02:01,470 --> 00:02:07,110 ‫In fact, as far as the compiler is concerned, one of the first things it does is just remove all comments 30 00:02:07,110 --> 00:02:09,390 ‫from the file because it just doesn't need them. 31 00:02:09,390 --> 00:02:13,620 ‫It ignores them when it's dealing with them and turning them into binary. 32 00:02:13,950 --> 00:02:21,420 ‫So what we want to do is write out a little plan for how we are going to make our platform move backwards 33 00:02:21,420 --> 00:02:22,860 ‫and forwards. 34 00:02:23,010 --> 00:02:30,330 ‫So the first thing we're going to do is update the location of our platform. 35 00:02:30,330 --> 00:02:36,570 ‫So move the platform forwards, so move platform forwards. 36 00:02:36,570 --> 00:02:37,710 ‫And how are we going to do that? 37 00:02:37,710 --> 00:02:42,330 ‫Well, I'm going to use some indentation to show that this is how we're going to be moving the platform 38 00:02:42,330 --> 00:02:43,170 ‫forwards. 39 00:02:43,170 --> 00:02:46,020 ‫We're going to get its current location. 40 00:02:46,020 --> 00:02:51,240 ‫Then we are going to add a vector to that current location. 41 00:02:51,240 --> 00:02:56,490 ‫And that might be a good place for us to use a local variable because we don't want that intermediate 42 00:02:56,490 --> 00:03:00,150 ‫result to be remembered at the class level. 43 00:03:00,840 --> 00:03:04,080 ‫Then we're going to set that location. 44 00:03:04,080 --> 00:03:07,260 ‫But what about sending the platform back? 45 00:03:07,260 --> 00:03:09,180 ‫Well, let's have another comment here. 46 00:03:09,180 --> 00:03:18,930 ‫Just at the indentation level below, we're going to send platform back if gone too far. 47 00:03:19,320 --> 00:03:24,450 ‫So what we're going to have to do there is check how far we've moved, first of all. 48 00:03:24,450 --> 00:03:29,520 ‫And if we've gone too far, we're going to reverse the direction of motion. 49 00:03:29,520 --> 00:03:36,570 ‫So reverse direction of motion if gone too far. 50 00:03:36,570 --> 00:03:45,510 ‫So here we have a very basic pseudocode description of what we're planning to do in the upcoming lectures. 51 00:03:45,510 --> 00:03:48,570 ‫Please go ahead and add this to your own C++ file. 52 00:03:48,570 --> 00:03:51,180 ‫You can use your own words to describe each step. 53 00:03:51,180 --> 00:03:53,580 ‫This is just my interpretation of it. 54 00:03:53,580 --> 00:03:59,340 ‫And because this isn't used by the compiler at all, it doesn't matter whether you have a typo or anything 55 00:03:59,340 --> 00:03:59,670 ‫like that. 56 00:03:59,670 --> 00:04:04,980 ‫The most important thing is that you just start each line with a double forward slash. 57 00:04:05,010 --> 00:04:07,230 ‫Okay, I will see you in the next lecture.