The function of the texture of computer graphics

When it comes to textures, it's hard to describe them in words:

I'll start with the picture:

Have you found anything?
Look carefully:
Our second model is to talk about the concept of texture mapping by giving the model some realism through texture mapping techniques.

Then we must not think that the second picture will certainly use texture mapping is not necessarily.

Now let's talk about the benefits of textures:
We have the texture, then we can put the surface of the model through the texture to cover up, so that our model people do not so hard to construct the model and material details, saving a lot of manpower and time.

If we stand at the pixel level, we just need to parse the coarse polygon correspondence and pixels to replace the detailed geometric shape.

Continue to fancy the texture of the teapot and not on the textured:

In fact, the texture is divided into 2 categories: 1 is a color texture and a geometric texture

According to the literal meaning, I believe you guessed it:
Color texture: We can show different texture details by changing the color or shading.
Image above

As shown in the figure is a different color and light and shade composition of the texture map;

So what is the geometrical texture?
When we hear the geometry, we certainly want to look at the shape of the pattern, so if the geometry of the model is not only color and light and shade, but also a bump feeling, more stereoscopic, but also with irregular many small bumps show the details

Image above

Talk about the texture for so long: Now let me talk about how the texture was born, or how it was done.
First of all, the textures we use in our games, we begin to use third-party software to make the appearance of the model we need;
We also call image texture: In fact, it is a map, which stores two-dimensional texture patterns, then the process of painting is to map the texture pattern of pixels one by one to the surface of the three-bit object

I'm going to figure it out first.

Then a texture: a texture pattern generated by a mathematical function, directly on the surface of an object, such as a checkerboard on a screen.

Now define the texture mapping concept left above:
Texture mapping (Texture Mapping): We use digital technology to overlay or map texture patterns to the surface of three-bit objects, and the process of adding surface details to objects is called texture mapping.

Texture mapping Idea: We need to find a texture space (u,v) coordinates to the three-dimensional object surface (s,t) coordinates between the mapping relationship, the texture space corresponding to the corresponding color parameter values mapped to the surface, so that the surface to get color texture details.

In fact, if we want to change the shape of the geometrical texture, we can use the perturbation function to change the geometrical shape by taking a small disturbance to the location of the sample point of the scene surface.