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Modelling lesson 4 -- Textures

Most materials would not be so easy to shade using physical description (the computations would be too cumbersome). This is why we use textures. We know two types of textures:

Textures are usually added in the shading editor as shown in the following tutorial. Note, that it is important, that a material needs to be assigned to the object if we want to add the texture:


The image textures have several settings which influence the mapping of the texture onto the object -- texture interpolation, type of mapping, the extrapolation of the texture on the boundaries. For the reference, see this part of the documentation: link Texture settings

Although, there are many ways how we can wrap the texture around the object, we usually need to adjust it manually. This is done using the UV unwrapping which consists of the following steps:
  1. Marking seams on the object, which allows us to unwrap the object. In other words, our aim is to develop the polyhedron, so it can be projected onto the UV plane, where the texture is placed
  2. Adjusting the vertices of the developed polyhedron

The details are found in the following video:


The procedural textures are created by following a pattern. Blender offers several procedural textures. The advantages of procedural textures are low memory requirements, however the final look of the textures is often not realistic. Quick guide on the procedural textures may be found here:


As we have seen so far, the textures do not have to influence the color only. Textures may be used also for advanced effects as modification of the transparency, normal vectors direction or the geometry itself. One of the most frequently used modifications is the normal and bump mapping which creates the detail of a certain material (e. g. the texture of a fabric, peel of the orange). However, these fine details are added only visually, by changing the direction of the normal vector. More details, how to achieve this, are found in this quick tutorial:


Assignment -- Textures

Aim

The aim of the assignment is to link your theoretical knowledge with the tools of the 3D modelling software Blender. The assignment is the result of the activity on the online lesson.
The third topic covers textures.

Modelling in Blender

Create a simple scene with several objects (e.g. sphere, torus, teapot, bunny etc.) and a plane, which serves as an underlay to these objects.

Each object has its own base color (set in Materials tab). The objects do not have to be textured.

Document structure

You will create a (.pdf) file with several dozens of figures. Each figure is described by few sentences describing the settings of a certain parameter, property or a object. Also, explain and show (if possible) the main principle, how the parameters are computed, or how they affect the scene.

Please, use separate figures (rendered images) and descriptions for each change of the settings of the scene.

Example:

example

Now the scene contains only one spotlight with the apex placed above the cube. The beam is characterized by the circular cone, with following parameters:




What has to be included and discussed

The front page -- includes the name of the project, your name, study program and academic year.
Mapping projection -- describe and compare the different types of projections. Use the same projection on the different types of objects (e.g. cube, sphere, cylinder, torus, plane etc.) and discuss if the certain type of projection is (not) suitable for the certain type of the object.
UV mapping on a square-pyramidal pyramid Create a similar UV unwrapping as shown for the cube. Create (or find) a simple texture, where each face of the pyramid is of different color and use it for the texturing.
Include also the printscreens from the process (e.g. texture with the default mapping of the pyramid, and with the correct mapping).

Bump/normal mapping -- include the height/normal maps, the textured object before/after the mapping. Create a realistic object (e.g. an orange, sofa with some kind of fabric) using the bump/normal mapping. Also include the close-ups of the detail.
Procedural textures -- choose an arbitrary procedural texture offered by Blender and describe its parameters and include examples illustrating them.

Submission rules

Your (.pdf) file together with the original Blender file(s) (.blend) are compressed into a (.zip) archive and submitted using the following form:
file_upload Submission form

The deadline is set to 14 June 2020 or 3 work days before the exam.

DO NOT COPY – PARAPHRASE!