对实际纹理 unit 设置当前纹理坐标 (v.x,v.y,v.z)。
在 OpenGL 中，如果提供了多纹理处理，则其与给定纹理单位的
glMultiTexCoord 相匹配。在其他图形 API 中，对应的
功能是模拟实现的。
The Z component is used only when:
1. You access a cubemap (which you access with a vector coordinate, hence x,y & z).
2. You do "projective texturing", where the X & Y coordinates are divided by Z to get the final coordinate. This would be mostly useful for water reflections and similar things.
此函数只能在 GL.Begin 与 GL.End 函数之间加以调用。
using UnityEngine;
using System.Collections;
public class ExampleClass : MonoBehaviour {
public Material mat;
private bool flagTex = true;
void Update() {
if (Input.GetKeyDown(KeyCode.Space))
if (flagTex)
flagTex = false;
else
flagTex = true;
}
void OnPostRender() {
if (!mat) {
Debug.LogError("Please Assign a material on the inspector");
return;
}
GL.PushMatrix();
mat.SetPass(1);
GL.LoadOrtho();
GL.Begin(GL.QUADS);
if (flagTex)
GL.MultiTexCoord(0, new Vector3(0, 0, 0));
else
GL.MultiTexCoord(1, new Vector3(0, 0, 0));
GL.Vertex3(0.25F, 0.25F, 0);
if (flagTex)
GL.MultiTexCoord(0, new Vector3(0, 1, 0));
else
GL.MultiTexCoord(1, new Vector3(0, 1, 0));
GL.Vertex3(0.25F, 0.75F, 0);
if (flagTex)
GL.MultiTexCoord(0, new Vector3(1, 1, 0));
else
GL.MultiTexCoord(1, new Vector3(1, 1, 0));
GL.Vertex3(0.75F, 0.75F, 0);
if (flagTex)
GL.MultiTexCoord(0, new Vector3(1, 0, 0));
else
GL.MultiTexCoord(1, new Vector3(1, 0, 0));
GL.Vertex3(0.75F, 0.25F, 0);
GL.End();
GL.PopMatrix();
}
}