A colleague recommended this application to me today, and I'm absolutely stunned. Without trying to be overly dramatic I believe VPaint is the kind of software the open-source animation scene has been needing for a good while. A simple goal-oriented application to actually create animation, and hand-drawn (with the occasional computer assisted inbetweening) no less!
I'll share a bit of my background. I'm an Independent Animator, I've directed the animation of a children microseries called "Capybara" and have used tools from pen & paper to digital cut-out puppetry to 3D animated techniques. Through my work I've been acquainted with different commercial animation software packages such as TVPaint Animation, Toon Boom Harmony, Anime Studio (previously Moho), CTP Pro Animation, Digicel Flipbook, among other hand-drawn animation solutions. So hopefully I can provide some concept and insight into features that are definitely used in production.
I hope it is ok to submit my inquiries here, I've already read all of the Feature Requests that other members have submitted, and I've removed similar entries I had for the sake of brevity. But I want to contribute to this software however I can since I believe it's an integral part of making a production ready tool.
I'll list a few critical elements and as time passes I'll add more, depending on how the program evolves.
- Frame content reordering: this is extremely important, because we tend to expand or condense the perception of time by reordering the distance between frames, this is what most people know as timing in animation. Copy and pasting the contents of a frame is not the same psichologically and phisically, since usually you draw the drawing the way you want it to be, like if it was on a single piece of paper (or frame), so you phisically had to reorder these to make sense of the action you're animating. I would imagine the frame container on the timeline could be given the property of being dragable and to "fit" in-between other frames.
- Create a loop button playback function to play the highlighted region: This is critical. You cannot review your animation by pressing continuously the space bar and the home button. Sometimes I take almost 10 minutes watching a looped sequence for inconsistencies in volume, weight, lines, etc.
- Onion skin opacity slider: This has been recommended before, but I must stress this as well. Your actual frame should be seen as solid, but the other frames, though visible, should recede in view because if every frame is 100 opaque, you don't know which frame is your actual drawing after a few hours animating a scene. Turning on and off the onion skin is the equivalent to turning on and off your light table. We dont do it every 5 seconds, you just turn it on, roll your paper (use your arrow keys) to see the flow of your animation and then you turn it off if you need to polish some detail without being bothered by the other frames visual.
- A Canvas Rotation Tool. If middle click = Pans, Alt+middle click = Zooms, then Shift+middle click should rotate the canvas. This feature along with a reset rotation button. There can be discrete rotation angles, but we require to rotate the canvas/ view most of the time to draw difficult elements. It's especially useful with Wacom's CINTIQ or Intuos Pro Tablets.
- Color Wheel + Color Palette Panel with customizable global colors: Usually when you're working, you need to add your colors to the drawing really fast, using a specific color palette developed by the Color stylist, but say you're coloring 5 minutes of animation and every drawing had one color wrong, global colors can save your life, just change the color in the palette and voila! there would be an interactive change on every applied colour that shares the same ID (I suppose this can be done with several methods, but I just mention ID's to illustrate the point). This is similar to commercial software like Illustrator or Toon Boom. (There could be in the future a specific color palette file format, perhaps like those of krita / grimp, to standardize the flow between open source software)
- Sculpt tool should have a toggle to affect individual line segments or edges (like it works right now) and to affect the complete "glued object" because at the moment sculpting the drawn element is difficult if it's composed by more than 2 lines glued together. Which is often the case with vector hand-drawn animation.
- Select /Deselect All should be frame independent, because if you use these features it selects everything both on the current frame and on the timeline. If i were to delete that It erase every framed created. Maybe there could be a toggle and a warning, but sometimes it is hard to differentiate where you are with too many drawings, so deleting on a per-frame manner is standard.
- Layers: Someone suggested the ability to import a background to trace, this is great, but In traditional animation people use levels, which are now layers. They are used a lot. We don't require many, to be honest. But up to 100 would be more than enough (unlimited if possible hahaha) This would allow us to import background and foreground elements. So it would be better to plan for this feature rather than just making one image available. This go in hand with the next point.
- A Virtual Camera for Mechanical Pans, Zooms, etc. Also to be used with layers to allow for parallax effect of the multiplane camera. The view would change but the default screen / canvas size doesn't. If you're filming at 720p or 1080p. The camera would help to maintain the aspect ratio and unity of the shots, while avoiding the absurd use of transformation tools to show depth or perspective through size variation (which if possible it is best to avoid when you don't have the draftmanship to support your spatial drawings). It's as if you have the entire canvas space to draw, and the camera viewfinder will help to frame the shots. The use of the depth feature to some extent, or a 3d space would make this an excellent tool that would even rival commercial software like Toon Boom.
NOT SO URGENT FEATURES: - A Quick Color selector Right now, selecting colours is ok. But having access to a few of the previous colours you have used would deffinitely help the workflow. This would go in hand with the Color Wheel + Color Palette Point
- Customizable frame colors, to mark which are keyframes breakdowns, and all that. This is really helpful.
- Exchanging the order of the sculpt tool and fill tool, so it becomes assigned to f3, because you use the sculpt tool more than you use the fill tool and sometimes it breaks the flow of work.
- Using the option "are skins pickable" should allow me to use the selection tool to box select the other elements completely, not just allow to pick them one by one. If i draw a ball or a character that has more than 2 lines, I would require to move the whole drawing. This is just an improvement on the feature, but it is not essential at all, I could just go to the previous frame and do it, but hey, what are feature requests for right?
- Numerical or percentage based sliders for vertex and edge outline size. Again this is just picking on it, but It seems I never get the width I want due to my own inability to be precise with the current slider.
- Visual Onion Skin Offset: This is something only a few good animation programs have, which is the ability to "offset" your drawings to trace over some elements. You already have the base, but in this method precision is based on visual accuracy. Imagine a button that would allow simultaneous X and Y position change. You'd press the button and place a marker, which is the X and Y coordinates that you want to track. Then you click again so the onion skin would appear to be "glued" to the cursor using the tracking marker as the center of the "transform" whenever you align it visually with whatever mark you made on paper, you click to accept the new "offset position".
The old way to do it on paper is to mark a cross on the element you're tracing, say a ball, then on the next drawing you rough out where it's going to be next, so you mark a cross there, then you overlay the paper and superimpose both cross' then trace over the drawing exactly where you want it at in the next frame. Examples of this can be seen in the book by Tony White "The animator's Workbook". If needed I can see to make a video example.

I don't want to sound demanding, and my apologies if everything seems pretentious, but it's been a while since I felt excited about a new piece of software. Trust me, there is market for this. A stable version with the minimum requirements for a professional animator would be worth A LOT. Beginners sprout daily, and they always go and try to reach for Pencil (I'm trying to help there as well) but the tool although promising, and having a few great artists working with the tool, it is nowhere near what VPaint could do in a few more months of hard collaborative work.
I'll go spread the word, hopefully more people will join and contribute not only to the programming aspect but to the artistic promotion of the tool. Thanks!!!!!