Attaching Textures to Materials | Qt Creator Manual

- Qt Creator Manual
- Attaching Textures to Materials
- Qt Creator Manual 4.13.3

Using Materials and Shaders ◦ Using 3D Materials

# Attaching Textures to Materials

You can use the Texture 3D QML type to attach textures to materials. You specify an image and how it is mapped to meshes in a 3D scene.

## Selecting the Mapping Method

To specify the method of mapping to use when sampling a texture, select UV, Environment, or LightProbe in the Texture mapping field.

UV mapping is the process of projecting 2D images to the surface of a 3D model for texture mapping. The letters U and V denote the axes of the 2D texture, because x, y, and z are already used to denote the axes of the 3D object in the model space. You can paint the polygons that make up a 3D object with color and other surface attributes from a UV texture map. Pixels in the image are assigned to surface mappings on the polygon. Usually this is done by programmatically copying a triangular piece of the image map and pasting it onto a triangle on the object.

UV mapping is used by default for diffuse and opacity maps. It sticks the image to the mesh, so that a particular same portion of the image always appears on a particular vertex, unless you animate the UV properties.

Environment mapping is used by default for specular reflection. It projects the image onto the material as though it is being reflected from the material. Using Environmental mapping for diffuse maps provides a mirror effect.

Light probe mapping is used by default for HDRI sphere maps of light probes. For more information about light probes, see Using Highlights and Reflections.

To use image data from a file, specify the path to the file in the Source field. To use a 2D Qt Quick QML type as the source, specify the type in the Source item field. The type is rendered as an offscreen layer. If you specify the source item, any image you might specify as a source is ignored.

Note: Currently, there is no way to forward input events to the Item used as a texture source.

## UV Scaling

The U scale and V scale properties define how to scale the U and V texture coordinates when mapping to a mesh's UV coordinates.

Scaling the U value when using horizontal tiling specifies how many times the texture is repeated from left to right, while scaling the V value when using vertical tiling specifies the repetition from bottom to top.

To control how the texture is mapped when the U scaling value is greater than 1, set the horizontal tiling mode in the U tiling field. To control how the texture is mapped when the V scaling value is greater than 1, set the vertical tiling mode in the V tiling field.

To specify that the texture is not tiled, but the value on the edge is used instead, select ClampToEdge. To repeat the texture and mirrored it over the x or y axis, select MirroredRepeat. To repeat the texture over the x or y axis, select Repeat.

## Setting UV Transform Properties

To offset the U coordinate mapping from left to right, set the position of the component in the U position field. To offset the mapping from bottom to top, set it in the V position field.

Specify the U and V pivot point in the U pivot and V pivot fields.

To rotate the texture around the pivot point, specify rotation as degrees in the UV rotation field. A positive value indicates clockwise rotation.

For more information about rotating and pivoting components in the local coordinate space, see Managing 3D Transformations.

## Applying Textures to Materials

Drag and drop an image from Library > Assets on a material to create a texture component. Dragging an image to a default or principled material opens a Select Texture Property dialog. You can select the property to attach the texture to in the Set texture to property field. For a custom material, you must assign the texture to a map.

To use Texture components to apply textures to materials:

1. Drag and drop a Texture component from the Library to a material component in the Navigator.
2. In the Properties view, specify the image to use in the Source field.

3. Select the material component and specify the id of the texture to use in the Properties view, Diffuse map field.

Using Materials and Shaders ◦ Using 3D Materials