Chapter 6: Texturing the 3D model

Building a texture is the last step in creating the finished model. A texture is like a wrapping for a present. We will create a 2D JPG file, that will be the wrapping paper. Fortunately for us, we can assign every pixel in that JPG to a specific point on the 3D model. This means, we can wrap the texture around the 3D model in a way, that the texture imitates the surface structure of the original. We can already see that in the coloured point cloud, but this colouring is not very accurate and can not be used in most 3rd party 3D software. If you want to use this model in a game engine for example, you would not be able to. Also, for documenting purposes, we need to have a complete export with a texture in an open format, so other software than Metashape can open it. We therefore need a texture.

Building a texture

To build the texture - the last step - please open the Workflow menu and select Build Texture.... For this example, we use Diffuse map mapping mode, the source data Images, the Generic mapping mode, Mosaic blending mode and a texture size of 8192x1. Hit the OK-button.

Additional information: The Mapping mode helps building the texture. Generic means, that the software tries to generate a uniform texture. This is especially recommend for arbitrary geometry. The Orthophoto option creates an orthographic projection (directly from above). This means that this option is best suited for flat objects or terrain. Adaptive orthophoto creates also an orthographic projection as a base, but textures vertical areas of the object separately. This option is best suited for nearly flat surfaces, like the façade of a building for example. Single camera uses only the data from one of the aligned photos and neglects the rest. Keep uv will keep the current texture parametrization. Some external software can use this kind of mapping mode.

The Blending mode option selects the way how pixel values from different photos will be combined in the final texture. Mosaic tries to combine two methods. The areas with no detail are blended from different photos to avoid seamline problems. Detailed areas are reconstructed from a single photo with the best quality. Therefore details appear very sharp in the final texture. Average uses only the blending option with no special interest to the details. Max intensity uses the photo with the most intensity and Min intensity uses the photo with the lowest intensity for each pixel. Disabled uses the most sharp photo for every pixel.

Finished 3D model

After selecting the Textured-button on top (where you also found the Model Shaded-button) you can inspect your 3D model. If you would like to save the progress, please do so in the File-menu. There, you can also export the 3D model into any 3D format you want, but this is something for another chapter. If you take the time and inspect the model, you clearly see that the texture adds to the details of your model. You can try to switch the view between Model Textured and Model Solid. These two views can show you which parts are really detailed (topography-wise) and which parts only appear detailed due to our texture.