DokoDemoPainter is a set of scripts and shaders for Unity3D that allows easy to setup texture painting on regular meshes and skinned meshes. It provides a pen, an eraser and a stamp, as well as functionality to fade texture changes. Modified textures can be saved and saved textures can be automatically loaded to make modifications seem persistent.

The easiest way to get started with DokoDemoPainter is to try out the included example scenes. The second easiest way is to add the DokoDemoPainterPaintable component to a textured object and add the included pen, eraser and stamp prefabs to the scene.

Most interesting settings are on the DokoDemoPainterPen and DokoDemoPainterStamp components. The settings on the DokoDemoPainterPaintable component allow further fine-tuning and the use of fading and texture saving. All fields have tooltips containing an explanation on what they do.

To make your own brush or stamp, add the corresponding component to a game object. It is also necessary to add a camera and set it in the component. The included prefabs can be used as a template for this.

You can try out a very simple live demo here. A demo using WebVR can be found here. The WebVR demo is based on Mozilla's Sunny Desert demo.

While active, every pen or stamp will render to a 1x1 texture every frame to detect painting targets. This means that every active pen or stamp in the scene will take some processing time.

Painting itself is done using a fragment shader, so no transfers of texture data between the CPU and GPU are necessary, so DokoDemoPainter performs reasonably well.

Using pens with alpha blending (e.g. soft pen tips or opacity below 1.0) will lead to a slight reduction of performance, because a second drawing history texture will have to be updated each frame. If performance is an issue, avoiding these functions may help.

Painting on objects with a high number of materials can also lead to reduced performance. If the number of materials cannot be reduced, it is possible to use the whitelist functionality of the DokoDemoPainterPaintable component to exclude unnecessary materials from the painting process.

The following types of objects may cause issues with DokoDemoPainter:

• Objects without textures. Materials have to have a set main texture, otherwise they cannot be painted.
• Objects with little space between disconnected parts of their UV maps.
• Objects where parts of the UV maps differ in scale.
• Objects with mirrored UV maps.
• Objects that reuse parts of their texture multiple times.
• Objects with weird UV maps.

Using the whitelist functionality, it is possible to assign different settings to different materials of an object by adding multiple DokoDemoPainterPaintable components.

Issues due to difference in scale can be reduced by adjusting the radius and size factors of the DokoDemoPainterPaintable component.

To avoid painting on unrelated parts of the texture when UV maps have little safety distance, brush sizes should be kept small. Reducing the maxDistance setting may also help.

If painting just won't work properly, the only way to fix it might be to adjust the UV map of the mesh itself.

If you want to build your Unity application, you have to make sure that Unity includes the following two shaders in the build:

• DokoDemoPainter/Detect
• DokoDemoPainter/Render

In the newest version, they have been moved to a "Resources" subfolder, which seems to take care of this issue. If not, try setting the player setting Keep Loaded Shaders Alive and add the two shaders to the Preloaded Assets list.

These settings can be found under Other Settings. Doing just one of these things may be enough to make it work, but it can't hurt to be sure either way.

DokoDemoPainter (code, models and textures) is distributed under the MIT license. This means that you can use it, modify it, distribute and so on in whatever way you like, as long as you include the copyright and license information with your program. It is not necessary to display this information on a credits screen or similar, as long as it is included at all, but it would be appreciated.

If you use DokoDemoPainter in your project, it would also make me very happy to hear about it.

While it is not mandatory, if you make any improvements to DokoDemoPainter, I would also appreciate it if you contributed them back so I can include them.

The rabbit model, textures and animations included in the example scenes are distributed under the CC0 license or public domain and were created by Čestmír Dammer.

DokoDemoPainter was made by Emiliana for Virtual YouTuber purposes, but it can also be used for games or other applications.