 So hi everyone. So that's what's it. Thank you Now I'm this is Emily. This is a research engineer focused on grease pencil at the special and I'm Flavio the city of the company and We are going to present Two open since we have been creating and that we are going to share We are starting with our I will just show you our demo reel for the animation demo reel We have made for the conference everything you are going to see is made on blender, of course Except for one project which is animated in Krita. That's it happens now We need we needed some more more bitmap style animation. So anyway, so yeah, this is the demo reel So we are an animation studio based in Montpellier in the South of France We have been working and sharing open source tools in eight years. We have been doing a couple of already conferences or so And we have been putting blender in the core of our pipeline There are some spoilers, but we're going to show you There is cut out stuff and keyframe stuff, it's a mix of stuff you can see here 3d helping you to the menu also Yeah, we like this hybrid images mixing 2d and 3d as you can see here few games So yeah, anyway In our studio the research and development Department is working on creating tools and tailored made for the projects of our clients and and today this is the Krita project and Today we are going to talk about the importance of open-scenes and test material for 2d animation In the in the 3d world the 3d research world models have been used for decades for testing And research aspects such as shading, you know, these kind of models Basic lighting features, I mean this scene you have probably seen dozens of times or hundreds of times And even if it looks simple it focus on very specific aspects such as bouncing lights and refraction and stuff like that There is not much artistic value on on these kind of scenes, but they are very important for technical Research and development, but that's not the point on all this one This is a remake of one other scene which is very used You also know this one by Christophe Sir Some scenes are created by companies some by the community Or universities and the classroom can be used for learning or test render engines or doing Benchmarks for example or doing the Gris pencil 3d demo this morning It's a benchmarking hardware and software also can be part of these missions On this one this every scene made by Disney to test usd pipelines and render engines with Millions of objects So there are any the 3d RNA benefits a lot from good resources for this kind of stuff and corporate to compare And this is only a limited list, but What about 2d? What about 2d? In 2d there are also resources that are available Mostly for image processing So I am sure you know this picture that's been used in many benchmarking of algorithm So that's a photo of course and the internet is full of them and some of them are like free for Use to test and research and stuff like this When it comes to sketches it gets a little bit trickier Actually, there's a recent paper a research paper that's been done and they have been collecting this full database of sketches black and white state sketches in order to benchmark rough sketch cleanup Algorithms so you can see that there's kind of a need to have this kind of resources and When it comes to 2d animation It's even trickier because for a sketch at least if you have some knowledge of how to draw or know someone It might not be that difficult to get this material But for 2d animation, you know that it takes much time much energy and Indian much money to like just have a test for just one algorithm so we Identified that there was a need to have this kind of scenes that are proposed for technical reasons and One of the thing that we might do is use the productions that we have at the studio the animation that we have but The problem we can came across last year is that we couldn't use most of like some of the images so we had to blur a small character like this one and Also, so this is a video that of the conference. I made last year about stroke mapping algorithm so it was to apply patterns on the dress of the the character here and Also at the end of this development We felt the need to push a bit the algorithm to try to make it work on more folded Shapes and maybe other shapes than just closing But at this point we didn't have any animation that had all these folds and you know, that's difficult to animate in 2d So we were thinking that can we create a scene that serves this purpose and as While we do it, maybe we can include some other constraints and other things that we want to test right now or in the future So we started to just something we could have used also the blend grease plenty grease pencil blender open scenes Which I don't know if you know this page. It's really helpful If you don't know how to Get it. There's a little demo on how to access it from the blender website Because it might be a bit tricky sometime So that's really useful. It's a really good showcase of the tool the grease pencil tool But it's not very tailored for technical testing and sometimes you can find Animations that have characters in them that have IP and you cannot really use them So we started to make a list of What we what do we want in this animation sequence? So of course, that's a lot But we didn't didn't want to put any limits in the first so that we had and then we had a brainstorm with our More artistic team to see what can be done with all of this and we selected a bunch of Constraints and criteria, so you can see that there's still a lot of them But we removed some because you can't really do everything at once And at this point on the talk I want to thank the CNC Which is the National Center for the cinema and the moving image It's the French agency responsible for the production and promotion of cinematic and audiovisual arts in France And they are funding our research project on grease pencil tools and they agreed that part of this funding will be Used for artists to do to like create these things that you're gonna see so I'm gonna leave it to Flavio So let's deep in deep dive on what we did so starting from this list of constraints we ask Leah Leah or creative One of our creative director in the studio to create a character. She was free to create anything And she presented Billy Billy. She's a woman with the character effects features such as the dress or the air She has a prop which is your 3d longboard There will be there are details also that we are not animating that will come later on on the process Which are for example the little stars on the dress or the tattoo on the back of you know This kind of details you remove from to the animation because they are too painful to draw and animate in the form one of our goals with last year Mafalda Test was to bring back details which are very time-consuming to animate so so yeah That will come later and and then we ask it Comey our animation one of animation animators to start working so What we are going to see it's what we bring in this in the scene which are which is now available online So this is the first step. This is a rough animation. We have we left also all the little doodles She did so maybe someone will be interested by to see the process To and in even attitude and stuff So we have this back and forward with us to see if it was good So we change the perspective to have this profile view instead of more Three quarters you and stuff like that So this is the primary key frames and secondary animation in this layer here. I'm in this crisp pencil object Then in the next step is what we call the tie down So we go through the animation through the rough animation and we make it more detail and precise This includes checking the volumes are correctly Following and the the model and there is no bad distortions and stuff like that I mean, this is completely the basic 2d workflow here We left also all the annotations Before going to the in and paint departments and for example all the red annotations here the charts are made for the in paint department to include the missing frames in between which is needed to be drawn later And this is the in campaign Made by Colleen In campaign in the art of choosing the right brush I mean here there is only one one brush but and the properties that the the thickness of the line the right colors and find the style Get back to the original artwork and providing also the missing interval frames And at the same time the in key is obviously the final drawing that you can see in the animation So this is the three animation layers you find and you also find Set Damien Who works as precisely calculated also the speed of the set to have a perfect loop because one of the demands was to have this Being looped and and not there is no curtain the animation and stuff like that But we wanted more than just this This 10 second loop Inside the animation. There is three third bloops So the first one is the idle And then the push and then the trick They can all work They just Use one of the loops or mix them together But when you are doing I know I don't know Working on a texture system to put on the dress You want to have a nice demo looping so people can see and there is no jump and you can focus on something So we ask the animator to to include that in her animation And then there is also specific elements such as the closes the error the props Which are animated in different layers so you can get rid of them and focus on on a problem if you want So if you want to work on a new system to animate a soft body 2d physics on dresses But you can just remove the dress and add your model on on top of it And now to know what are the use case of this scene? I just let Emily talk about that So what are the use cases? Uh, I think there's a lot so we're going to present just a few that we thought about or worked on already The first one is the first addon that I actually made in blender It's the color picker. So for this it's more for illustrating the tool that's uh, actually Colleen who did the ink and paint Already used the color picker on another prediction So she was able to create the palette and create all the thing and use it So we are going to share also this palette so that people can try the color picker and eventually like and also like try it on the scene itself Another possible Use case will be to test for color changes So we did a small like a color mapper, which is the beginning of a development that We started last year and I think for like Changing color scheme like changing the lighting in 2d and stuff like this. It could be great to test it on this scene And especially since the background is also made in grease pencil You can completely change the color of the image within blender The only the other thing also is the stroke mapping that I talked about earlier So as Flavio said, there are some more details in the dress and also the frackers in the skin That we want to see if we're able to like help Including this in the animation Not by drawing it in every single frame, but see how can we Develop tools to help that and then two ideas of Development that we didn't start on but maybe in the future or maybe you want to do it First is interpolation. Of course, it's a really big topic in 2d So I think this kind of scene can be useful to test like in the either part It might be easier to do interpolation and then in the the trick part It it comes with many challenges because the character makes a turn And then another thing that Could be interesting in is Doing clean assist meaning like from rough to ink Maybe not automatically But maybe have some tool to help in this step because we know that it can be a bit long to do And since we are providing all the steps of the fabrication, it might be Useful to to test these algorithms So the scene is available on our git lab the blender scene as well as we are going to put all the designs early designs that Alia made and Yeah, you can Download it and test it and use it on your Papers on your presentation. That's made for that So then So this thing concludes our first example of tools made to help traditional digital 2d animation We have also another research axe, which is how can 2d help 3d in the studio From its render to create more visual hybrid solution and techniques. So last year we presented the also I mean you saw some extracts in the in the demo rail of this project and the idea was to Use grease pencil to draw the smears, but then made a three triangulation from that to have a nice Three shape that we can shade And and light in a proper way so it integrates with the character with a nice shading You can show you can check amelie's last year talk if you want on our taking care blog If you want at the same time of these last summer We were working on this pilot and also the 2d feature film and two of the compositing artists of the future julien Which is here in the world and Jean-Baptiste Marchand Started creating great paper cutout stuff on evenings with the material of the company And actually they did an exhibition at the end of the last last year summer So there is this part of this exhibition. It's made of out of paper cut And it was amazing This is actually me And my kids on the other side Uh, I love this illustration mood of it. Uh, it's designed on computer This is this drone on crita. It's then splitted and victorial blocks using illustrator And then the final cut is made with a computer controlled cutting machine And here you have and each piece each part each piece Which are hundreds on this kind of poster are carefully sticked together piece by piece to to make a billboard So we feel the physicality of it and the layers and the textures It's great and you have these little details all over the place. There is depth and It's subtle from far, but you feel it when you are close to the poster You feel the depth and it's obvious from close So we were wondering how we can you we can use that kind of stuff also in animation There are some shorts and advertising made out of cut cut cut out paper But it's expensive because it's very long to cut and prepare and everything So you don't see tv series or stuff like that with this technique Because it's too time consuming. So we made this mood board with paper inspired work from great authors And you can see here the texture the lighting was something we were very interested in The backlight and how the light spreads through the paper and stuff like that So we want to include that in in something more elaborate So we had this mood board and we added a list of constraints we like so we want depth We want a paper style result. We want dynamic lighting It must be quick to animate So there is flat design no textures for now No constraints in terms of layer and shape for the animator is free to do whatever he wants And we aim for a 10 second Short so We asked Julien to create something and he made this concept art Um I mean with the goal of sharing the scene later, of course Julien really likes drawing pigs as you have made noticed in the the billboard before It's a subject you can see a lot on his instagram So he wanted to do a take on this famous story So we left the concept and it was a go for the next step and here is the the rough animation he made In the in the afternoon. He's very fast Um So we have this So yeah, we loved it and we asked him to to extend it actually So it included the camera movement so we can put parallax and test this kind of stuff Running cycle and stuff. So here is the directly the final animation. Yeah, there is no song that can Do the So Um, he made that in a couple of days. It's I mean, it's very fast responsible and actually Actually, everything in the scene is gris pencil. The background is gris pencil. There is no Meshes here There is no textures. Uh, everything was done drawn in gris pencil There is 12 seconds of animation 310 frames 5 gris pencil objects and 24 layers if you are interested in statistics And yeah, so we have these already Spacely Separated layer and stuff like that. You can see here the drawing some some of the shapes are not closed and stuff So this one's not in constraint. We wanted really him to be free to animate whatever he wanted And yeah, this is what we have at the same time Yeah, so at the same time, uh, we if we go back to the visual results We are looking for in the mood board. We have this image From mao le moine, uh, which is a paper cut Schoolwork made 10 years ago and uh, it's a very nice design and a very smart usage of just one Sheet of paper, you know, it's and we wonder can we do that in 3d? So this is our our take on it dania made this To replace the concept. I think it catches well the paper effect and the deepness of it and the texture So you can see here in the viewport What this looks like? You know the you know the texture of the paper and stuff like that So this was just a quick test and uh, we wanted to apply this to uh, to do to the crisp pencil. So, uh, We have a lot of issues to call tackle. So I just asked Emily to handle that and she will explain Okay, so the idea was to uh, go from the animation of julian In gris pencil and to get that kind of 3d effect The take we had on it. So you can see like the in and out Was to convert actually the gris pencil into a mesh or meshes so that we can use Anything in blender like 3d blender properly you can put textures materials effect, of course and lights camera movements as you want. Yeah So how to do this So the basis of our algorithm is actually the same than last year like convert A stroke gris pencil stroke into a mesh. So a triangulation algorithm basically In which we can add then some depth with some modifiers You can also animate it through visibility parameter So you're going to have lots of meshes because for 2d each frame is a different stroke, of course So it's going to be a different mesh at the end But if you just do this, so I just added this year two things The first thing is the outline because for lines So we really wanted to capture the same shape as what you want you have in the screen So you have to first compute the outline and then do the triangulation And also holes because it was it felt like it was kind of important for the lighting effect to be able to have holes in the shapes So in gris pencil holes are done with holdout materials And then we included it in the triangulation which is done with the triangle library So then you can do that for every single stroke of the animation But what happens if you did do this and then try to render it Is that you get this dark Areas and that's because when you're drawing gris pencil you you do overlapping between shapes, of course So at the end is going to be in the same plane and overlapping and the rendering engine doesn't deal very well with this And that's also because in gris pencil the order of visibility of the strokes is decided by the order of when you draw Of course, so one thing you want to add right now is depth like actually Really positioning the different meshes So a first take on it a first naive take is to Create an algorithm to add some depths to every single stroke And that's done by a greedy algorithm that just decides Okay, the stroke is going to be at the depths where at the lowest Sorry, the lowest depths in which it doesn't overlap with another stroke. That's simple So for example here, the body of the rabbit is uh, you can see my It's a depth zero because it's the first one that was wrong Then the second one is the head and it actually overlaps with the body So it gets depth one And then for the ears they get both depths two because they don't overlap with each other So they can be at the same depth level So the rendering that you can see on the right It's better because then you don't have these dark areas But what you can see is that you can see the outline I don't know if you can actually see it the outline of the ears and the head And it creates some cast shadows and that's actually what we want But maybe not inside of the rabbits because when you draw this in gris pencil, you don't really see This boundaries and actually you see them only if the drawing Behind it has a different material or has a different color So you want to include that in the algorithm So now we are Computing the depths, but actually putting at the same depth level Stroke that have the same material and then you can merge them at the stroke level and then do the triangulation So for example Here the body and the head have the same material so they get merged and they get triangulated But for the ears actually they have a different material because there are stroke and not fill So it's a different material in gris pencil so Actually, we just adjusted this so that it takes the color instead of the material because it felt like it was better for like a Keeping the visual appearance of the drawing so Yeah, so i'm just illustrating this this point on this one this design At the top we are Okay, the text is not very well displayed At the top is the the result when we separate by by material So you can see that the little details at the top are pop out of the the rest of the decor And at the bottom is if when you do when color with color And in this case the little details are merged with the rest of the shape So it's just a aesthetic choice. I think but for us it felt like it was better to do it by color Of course, this works only if you work with flat colors and not like textures and gradients So I guess you have to come up with another solution for this That's another result on the head of the the wolf so At the left is the grease pencil and on the right is the rendering with some cast shadows It's a bit subtle right now, but you're gonna see in the result with the lighting how it performs So we did that for At the frame level so it drawing level one frame one layer and it works well, but now what happens between layers And for this to illustrate this Here is the wolf and you can see the different layers that were done grease pencil in the top And in particular the arm is in another an ol layer like here And that's two takes on this issue Either you say, okay Each layer is going to be at a different depth because you draw one layer and then paste one another on top of it Or you say no every layer is just a Big pile of strokes and you can merge in between layers That's just two different takes of the issue So we kept it as an option And actually you may might want to do it differently per grease pencil object depending on what you want to see So here in the result, I don't know if you can see it But on the left the arm pops out of the shape and then on the right It just blended with the the head of the wolf So just some limitations that we saw so the first one is a kind of an inconsistency between the triangulation that shows in grease pencil to display shapes And the triangle library one So here I don't know if you can see the the stroke on the left But it's a bit misclosed and a bit messy and actually creates a hole in the triangulation Um for to overcome this we actually just fill the shape in the mesh because it was easier And actually it really happened a few times maybe less than 10 Strokes where had this issue in the whole animation. So it was okay, but uh, yeah, I don't have a solution for this And then another issue was um Connected to stroke ordering because sometimes different Stroke ordering of the same during that will give the same result in grease pencil would Give different results in the rendering so here Two two different ordering of the stroke give either like the nose of the wolf pops out or it smelch So in this case for to solve it you just have to go back to the grease pencil and change the stroke ordering Which is a bit annoying actually But also it was really less than 10 strokes of the whole animation. So we did it this way That's really because the algorithm for ordering The the depth is greedy and then it cannot go back on a decision him it made before So maybe there's a better algorithm for this but for now it was just really little artifacts and it was not in the whole animation It was okay The last thing I didn't talk about was non-planar strokes And actually while we dealt with this with the triangulation or triangulation can deal with non-planar stroke We didn't really deal with it in this case because First julian didn't draw any non-planar stroke because it's not really easy to do this in grease pencil and you It's not really intuitive And also I don't exactly know how it would behave with the visibility and the layers and stuff like this So I guess it's still an open issue for me. So if you want to tackle it So now that I've talked a lot, I'm going to show you the result and then discuss the rendering Okay, so Here is another view of the scene with the shading and lighting. I don't know if it's Okay, so there's Ambient lights that is blue so that it creates a night effects Then you can see there are aerial lights in between layers of the the background there's a backlight on the On the little light that the pig has and also we put some emissive material so that it emits lights from the material of the the little lantern You can also see that sorry Okay, you can also see that we used some transparency in the house so that we can see the shadow and the silhouette Of the pig while it while it enters the house We're gonna see it. So that's the emissive material Yeah, so here we can see the silhouette of the pig and then for the wolf we We put a light on it that follows him. It's a bit like in seatory, you know So yeah, we did that to see it more in focus. You can see the aerial lights here Some of them are actually have negative values to darken the foreground And yeah, so it's a bit Mixed between stuff that we could do in stop motion Like putting lights in some places But also stuff that we couldn't really do like putting emissive material And actually have light popping out of the paper And also the negative values of the the light, of course So here you can see a comparison between the crisp pencil and the 3d rendering in particular the the background that Gained many many like depth because of the different lights on Yeah on the background so That's it. Our githlab is full of tools that we all share and also these open sequences if you want to test them We also have a technical blog, which is sometimes filled with articles and Also, we added a page on our website for all the tools and technical stuff. So Thanks before the question I will just show you this is a composite version made by julien of this sequence So this scene is available We are going to add some more material soon with which is our which are the actually the the first background test We didn't include in the blender file, but you can get them and Here is the This so this is actually this is out of lighting from from vendor. There is no compositing the lighting is was made last last week It's pretty recent. So it's not finished And This scene will be available in our gith in the incoming weeks. We didn't have finished it yet. So yeah So thanks for your attention. So do you have any questions? Maybe Yes Oh, yeah, okay. Uh, the question is uh for the The scene was a pig when I Converting the The grease pencil to the mesh I did it at once and not like real time. Uh, like it would be done in geometry nodes Actually, I'm just using a python script and Convert and then it becomes a mesh and that's it. I'm not Going out of blender So for the question is how how can we have an animated mesh sword in blender? Actually, so there's lots of meshes and it's animated by visibility attributes on the object Because I there was no other way so But yeah, if there's a geometry node solution for this, that would be great Yeah, so the question is when we do this depth positioning, how can we keep the visual aspect? actually in the in this play that I show I purposefully Just Widen the gap between the different meshes, but in the real scene it's way more closer So I have a parameter to like for the thickness of the paper and also another one for the gap But usually it's really really small. It's just for the rendering engine to be okay with it So is there another question? Okay. Thank you for