WEBVTT X-TIMESTAMP-MAP=LOCAL:00:00:00.000,MPEGTS:0 00:00:00.000 --> 00:00:02.805 Hello everyone and welcome to a new section. 00:00:02.805 --> 00:00:06.150 This one is about creating graphs for our modern house. 00:00:06.150 --> 00:00:08.370 At the moment, it's just a dirt lawn 00:00:08.370 --> 00:00:09.810 and that doesn't look very good. 00:00:09.810 --> 00:00:11.160 So let's add in some particle 00:00:11.160 --> 00:00:13.080 systems and create the grass. 00:00:13.080 --> 00:00:14.580 First. In this video, 00:00:14.580 --> 00:00:17.130 we're gonna talk about how to add in a way paints so we 00:00:17.130 --> 00:00:20.295 can actually determine where we want the grass to be. 00:00:20.295 --> 00:00:22.095 It's important to do this because 00:00:22.095 --> 00:00:24.030 all the way over here on the right side, 00:00:24.030 --> 00:00:26.325 the camera is not going to be able to see this. 00:00:26.325 --> 00:00:28.890 That means we don't need a bunch of particles over there. 00:00:28.890 --> 00:00:30.930 That's just going to slow down the render. 00:00:30.930 --> 00:00:33.120 So I'm going to show you how you can limit 00:00:33.120 --> 00:00:35.760 where the particles are using weight paint. 00:00:35.760 --> 00:00:39.230 To get started, we need to select our object and then go 00:00:39.230 --> 00:00:40.880 over to the object mode and 00:00:40.880 --> 00:00:43.490 switch it over to the weight paint mode. 00:00:43.490 --> 00:00:45.995 You can see everything is blue. 00:00:45.995 --> 00:00:47.870 That means there's gonna be no particles. 00:00:47.870 --> 00:00:51.335 If we assign this vertex group to the particle system, 00:00:51.335 --> 00:00:54.710 how weight paint works is it deals with values from 0 to 00:00:54.710 --> 00:00:57.995 10 is the blue color. 00:00:57.995 --> 00:00:59.210 And if I start to paint, 00:00:59.210 --> 00:01:01.850 you can see red is the a value of one. 00:01:01.850 --> 00:01:03.740 The grain is probably about halfway, 00:01:03.740 --> 00:01:05.450 maybe a value of about 0.5. 00:01:05.450 --> 00:01:06.620 So that means there's going to be 00:01:06.620 --> 00:01:10.115 about 50 percent of the particle density in that area. 00:01:10.115 --> 00:01:11.960 I'm going to Control Z that well, 00:01:11.960 --> 00:01:14.600 we're actually going to do is use the gradient tool. 00:01:14.600 --> 00:01:16.460 We don't need a ton of particles in 00:01:16.460 --> 00:01:17.780 the background because you're not 00:01:17.780 --> 00:01:19.445 going to be able to see that very well. 00:01:19.445 --> 00:01:21.410 So we're going to create a gradient effect where 00:01:21.410 --> 00:01:23.450 most of the particles are going to be closer to 00:01:23.450 --> 00:01:25.460 the camera and then it slowly fades 00:01:25.460 --> 00:01:28.085 as it goes back to the brick wall over here. 00:01:28.085 --> 00:01:30.875 To do this, we're gonna go into top view. 00:01:30.875 --> 00:01:32.480 And then we're going to position 00:01:32.480 --> 00:01:34.115 our view right about here. 00:01:34.115 --> 00:01:35.540 Where you can do is select 00:01:35.540 --> 00:01:38.825 the gradient tool with a strength of one for the weight, 00:01:38.825 --> 00:01:42.560 we're going to click and drag all the way back here. 00:01:42.560 --> 00:01:44.855 Something like that. 00:01:44.855 --> 00:01:46.610 I might actually do that one more time. 00:01:46.610 --> 00:01:48.395 So I'm going to click the gradient tool, 00:01:48.395 --> 00:01:51.920 click and drag until it's right about there are so, 00:01:51.920 --> 00:01:55.280 so we get some nice blue in that area. 00:01:55.280 --> 00:01:59.015 Then what we can do is grab the brush tool, 00:01:59.015 --> 00:02:01.655 set the way all the way down to 0, 00:02:01.655 --> 00:02:03.260 and then paint out where we 00:02:03.260 --> 00:02:05.390 don't need the particles to be. 00:02:05.390 --> 00:02:08.315 We're gonna go into camera view by hitting 0. 00:02:08.315 --> 00:02:10.430 And then we're just going to go along 00:02:10.430 --> 00:02:13.250 the wall right here and paint out what we don't need. 00:02:13.250 --> 00:02:15.800 Some shortcuts that you need to keep in mind is 00:02:15.800 --> 00:02:18.020 F is to change the size of your brush. 00:02:18.020 --> 00:02:19.280 You can move it out here if you want 00:02:19.280 --> 00:02:20.960 a bigger brush and then you 00:02:20.960 --> 00:02:23.105 can just click and drag to paint away. 00:02:23.105 --> 00:02:24.680 I'm going to dry my brush a little bit 00:02:24.680 --> 00:02:26.750 lower though, and then zoom in. 00:02:26.750 --> 00:02:29.375 What we can actually do instead of painting 00:02:29.375 --> 00:02:31.550 all of this because that's going to take a long time. 00:02:31.550 --> 00:02:33.590 We can go into edit mode, 00:02:33.590 --> 00:02:36.935 then switch over to the vertices select mode. 00:02:36.935 --> 00:02:40.190 You can press Alt 8 to de-select and then click and 00:02:40.190 --> 00:02:43.400 drag where the vertices are that are outside the camera. 00:02:43.400 --> 00:02:46.145 You can also press Z to go into wire-frame. 00:02:46.145 --> 00:02:48.320 And then we'll do the same thing over here. 00:02:48.320 --> 00:02:50.720 We don't really need those vertices. 00:02:50.720 --> 00:02:52.295 And then we don't really need 00:02:52.295 --> 00:02:53.390 these vertices in the middle. 00:02:53.390 --> 00:02:55.460 So I'm going to click and drag using circle, 00:02:55.460 --> 00:03:00.140 select, something like that or so. 00:03:00.140 --> 00:03:02.690 And then also we don't need any 00:03:02.690 --> 00:03:04.820 of the vertices there air that are in the back. 00:03:04.820 --> 00:03:06.710 So we're gonna go into top view. 00:03:06.710 --> 00:03:09.380 And then I'm going to press B for box select and 00:03:09.380 --> 00:03:12.320 draw a box around all of these vertices. 00:03:12.320 --> 00:03:15.200 And then also we don't really need any of these vertices. 00:03:15.200 --> 00:03:16.790 So we'll go back into camera view, 00:03:16.790 --> 00:03:18.830 box, select all of those, 00:03:18.830 --> 00:03:20.390 and then just use circle select 00:03:20.390 --> 00:03:22.520 and grab all of these ones. 00:03:22.520 --> 00:03:24.320 Just like that. 00:03:24.320 --> 00:03:25.760 So now that we have all of 00:03:25.760 --> 00:03:28.130 the vertices that are outside the camera view, 00:03:28.130 --> 00:03:32.330 we can remove that vertex group from these vertices. 00:03:32.330 --> 00:03:34.070 We need to do this by going over to 00:03:34.070 --> 00:03:35.960 the object data panel. 00:03:35.960 --> 00:03:38.240 Then with this vertex group selected, 00:03:38.240 --> 00:03:39.890 we're going to click Remove and 00:03:39.890 --> 00:03:41.855 that's going to remove the vertex from that. 00:03:41.855 --> 00:03:43.490 So now if we go out of edit mode 00:03:43.490 --> 00:03:45.440 and back into weight paint mode, 00:03:45.440 --> 00:03:47.660 you're going to notice that everywhere is blue 00:03:47.660 --> 00:03:50.090 except for the parts that we select it. 00:03:50.090 --> 00:03:51.560 Now that that's out of the way, 00:03:51.560 --> 00:03:54.690 we can start working on the particle system.