Blender – Grease Pencil and Line Art Modifier

hello and welcome back to the channel today I want to address a question that was asked on the cad tutor Forum a while back which was how to render a model in AutoCAD with the edges displayed basically like a line drawing now this question was asked back in 2022 and my reply was to export the blender and do the rendering there and I provided a very quick example of how to do it but I didn't really get into much detail if you're interested in reading through that thread there's a link in the description but anyway uh the thread was recently brought back to life by someone offering advice that simply doesn't work in AutoCAD so I decided to make a video showing how I would do it in blender now here's a model that I made in AutoCAD for one of my other videos but I don't want to get into a bunch of AutoCAD stuff because that's not really what this video is about and I've already covered exporting in another video so I'll link to that one in the description below so you can check it out but to keep this video short and on point I'm just going to select this model type export choose the STL format and hit save okay here in blender I'll delete the default Cube and and light and I'll go to file import STL and then I will browse to the location of my STL file I'll select it and I need to scale it down because my units in AutoCAD were inches and my units here in blender are meters so I'm going to give it a scale factor of 0254 and then I'll hit import and sometimes when I import STL files I'll get these shading errors but uh it's pretty easy to fix just select your model right click and then you want to shade Smooth by angle and that takes care of all those errors now for lighting I could set up a whole studio lighting rig but to keep it simple I'm just going to use an hdri image so I'll go to World Properties I'll click on this little yellow dot next to color and I'll choose environment texture then I'll click on the folder and I'll browse to the location of my hdris and pick the one that I want I'll use this one and now I'll switch the viewport display to rendered and I'll go to render properties and change to cycles and I want the device to be GPU compute so that my graphics card will handle the rendering and not my CPU I have a couple videos that go into detail about hdri lighting and rendering so I'll link to those below if you want to check them out now this background is distracting so over here in the render properties I'll scroll down to film and check transparent and that will make the hdri background image disappear but the lighting is still working next I'm going to move my camera and position it roughly where I think I'm going to want it then I'll hit zero on the number pad to jump into camera view and I'll open up the side menu and switch to view and make sure camera to view is selected and that will allow me to zoom and pan around within the camera view to get the model positioned roughly where I think I'm going to want it for the rendering now if I select the camera and come over here to the camera or the object data properties for the camera I can change the focal length to something else if I want it to be 35 mm or 20 mm or whatever I'm going to leave it at 50 mm though for this rendering now I'll hit uh I'll hit zero on the number pad again to jump back out of camera view and then shift a and I want to add plane and I'm going to scale it up and move it over so that it's underneath the model so that I have something for the model to sit on and now I'm going to hit zero on the number pad again to jump back in because I want to make sure this plane is going to cover the entire area within camera view something like that and now with the plane selected I'll come over to the material properties I'll add add a new material and I'll call it ground and I'm going to set the color to something darker maybe maybe something like that next I need to select the camera and the plane up here and I need to drag it out of this collection so going to drag up and I'll drop it onto the scene collection to get it out of there the only thing inside this collection needs to be your model or models if you have more than one that you want to have the line work applied to everything else has to be out of this collection now if I hit the home key on my keyboard the camera view will fill the full screen and then I'm going to close this side menu by hitting n and I think I want to make this ground plane a little bit darker maybe like that so now that everything's set up we can do the line work so I'm going to hit zero on the number pad to jump out of camera view and I'll hit shift a go to grease pencil and I'm going to select scene line art and right away you can see that this line art item has been added to the collection and we now have Line work applied to the model and if you pan around it looks like something's wrong like the line work doesn't cover the whole model if you look at it over here and over here you've got it overlapping but it's actually fine the line work is generated only within the camera view if I select the camera and I move it you can see the line work is moving on the model so we'll hit contrl Z to put the camera back and I'll Zoom back in here because the line work is a little heavy so with the line art selected I'll go to the modifier section and you can see there's a line art modifier that's been applied to the model and I can adjust the line thickness here so I'm going to set it to 8 because I think that looks pretty good so now I'm going to go to the output properties and I need to change my resolution and I'm going to set this one 38 4 40 and this one 2160 which basically it doubles what what was here by default and it will end up giving me a much sharper render and I'm going to go to the render properties and come down to light paths and I want to turn off reflective and refractive because I I don't need those and those will just increase uh the render time and now I'll hit zero on the number pad to jump back into camera view to see how we're looking and then I'll hit F12 to render and it'll take a minute or so and it won't look like the line art is working but once the render finishes you'll see the result and there it is so now I'll close this because I I want to add some color to the model so I'm going to select it and then I'll switch to the shading Tab and I'm going to add a new material and this will allow me to adjust the base color and give it whatever color I want think I'll make it a blue something like that and I'm going to do one more thing because I I don't like where the light is coming from so I'm going to switch from object to world and now this is this is my hdri so with it selected I'm going to hit contrl T to add a mapping node and a texture cord ordinate node now you need to have the node Wrangler enabled in order to do that so just come up to edit preferences go to add-ons type in node and then make sure you have the node rangler enabled so now in the mapping node I can adjust the rotation of the hdri so if I rotate around maybe 180° or maybe 150° that's probably fine now I'm going to switch back to object because I want to adjust the roughness a little bit here just make it a little more shiny something like that so now I'll hit F12 again and wait for it to finish and there you go and to save it come up to image save as and you can change your file format if you don't want PNG but I'm going to leave it as is and hit save image and here's the final render Zoom right in it's nice and crisp and clean looks pretty good okay that's going to do it for this one hopefully you found it helpful and if you have any questions or comments go ahead and post them below and as always if you found this video helpful give it a thumbs up and consider subscribing thanks for watching and I'll see you on the next one

Channel: Rod DeWeese

Views: 254

Keywords: blender, lineart, 3d rendering

Id: fxhVlQU56sg

Length: 13min 9sec (789 seconds)

Published: Sun Jul 07 2024