WEBVTT 00:06.860 --> 00:07.970 Welcome back. 00:08.000 --> 00:15.170 Thus far, our gameplay effects that affect our health are reaching in to our attribute sets and changing 00:15.170 --> 00:17.150 the value of health directly. 00:17.180 --> 00:23.360 Now, in more complicated RPG style games with gas, this is not typically the way we do it. 00:23.360 --> 00:30.650 And that's because whenever we apply damage to an enemy, for example, there are a number of calculations 00:30.650 --> 00:37.730 that should be made, and those calculations have to do with attributes both on the attacker and the 00:37.730 --> 00:38.480 victim. 00:38.510 --> 00:45.620 For this reason, to keep the mathematics simple, we often use a placeholder attribute that behaves 00:45.620 --> 00:52.520 as an intermediary, allowing us to perform all of the math that we need to perform before actually 00:52.520 --> 00:54.690 setting the value of the health. 00:54.710 --> 01:01.820 In the case of damage, these intermediary values are referred to as meta attributes. 01:01.970 --> 01:06.990 Now, here's the difference between a meta attribute and a normal attribute. 01:07.020 --> 01:16.130 A normal attribute is often replicated and it can be changed on the server and replicated down to clients. 01:16.140 --> 01:23.860 Whereas a meta attribute, on the other hand is not replicated and it's really just a temporary placeholder. 01:23.880 --> 01:31.110 We only use these on the server to perform calculations and after those calculations are performed we 01:31.110 --> 01:35.800 can then apply the change to the real attribute that matters. 01:35.820 --> 01:42.930 Now, in the case of damage, for example, we may have a meta attribute called incoming damage. 01:43.050 --> 01:45.090 Now it's not replicated. 01:45.090 --> 01:46.890 This is a meta attribute. 01:46.920 --> 01:48.600 Now here's how it works. 01:48.690 --> 01:53.180 Let's say a gameplay effect is going to apply damage. 01:53.190 --> 01:58.140 Let's say this gameplay effect says I'm applying 11 damage to you. 01:58.170 --> 02:05.340 Now, rather than subtracting 11 from the health of the victim, the gameplay effect is going to add 02:05.340 --> 02:09.690 11 points to the incoming damage meta attribute. 02:09.960 --> 02:14.610 Now we have ways to respond to attribute changes in the attribute set. 02:14.640 --> 02:21.120 For example, we can use post gameplay effect, execute and check to see if that attribute that's changed 02:21.120 --> 02:23.700 is the incoming damage meta attribute. 02:23.730 --> 02:27.690 Now if it is, we can perform any necessary calculations. 02:27.690 --> 02:33.780 We can determine if there was a block by taking in the victim's block chance we can determine if there 02:33.780 --> 02:40.200 was a critical hit, if there needs to be an intelligence bonus in the case of magical damage, for 02:40.200 --> 02:43.830 example, or does there need to be a strength bonus? 02:43.830 --> 02:48.020 Maybe it's physical damage and strength boosts physical damage. 02:48.030 --> 02:55.260 Whatever the case, we perform any of those calculations to determine the final real amount of damage 02:55.260 --> 02:56.490 that should be caused. 02:56.490 --> 03:03.680 And then we take that attribute in this case health and subtract that number from the health. 03:03.690 --> 03:12.230 So the gameplay effect is not the actual decider of how much health is subtracted from the health attribute. 03:12.240 --> 03:18.210 It's the rules that we set based on those mathematical equations that determines the final value. 03:18.390 --> 03:25.740 So this incoming damage meta attribute will be set by these damage gameplay effects and the attribute 03:25.740 --> 03:32.880 set will perform any calculations it needs to and then zero out that incoming damage meta attribute. 03:32.880 --> 03:40.320 In a sense, it'll consume that value in its calculations and set the value of health and also respond 03:40.320 --> 03:42.780 in any other ways that we need to respond in. 03:42.810 --> 03:50.550 For example, when taking damage, perhaps we need to show some floating text popping up on the screen. 03:50.790 --> 03:56.040 Maybe that floating text is a different color depending on if there was a block or a critical hit. 03:56.430 --> 04:01.140 Maybe the attribute set determines that there was a debuff in response. 04:01.140 --> 04:06.030 If it was fire damage, maybe the victim will be burned for a moment. 04:06.030 --> 04:10.560 Or if it was lightning damage, the victim will be stunned for a moment. 04:10.770 --> 04:17.190 These are things we can do in response to receiving a change in our incoming damage meta attribute. 04:17.430 --> 04:23.670 So meta attributes are the way that we often see gas projects handling damage, and that's how we're 04:23.670 --> 04:26.220 going to implement damage in our project. 04:26.310 --> 04:28.050 So we'll do that next. 04:28.080 --> 04:29.310 I'll see you soon.