GL

説明

低レベルのグラフィックスライブラリです。

Use this class to manipulate active transformation matrices, issue rendering commands similar to OpenGL's immediate mode and do other low-level graphics tasks. Note that in almost all cases using Graphics.RenderMesh or CommandBuffer is more efficient than using immediate mode drawing.

GL immediate drawing functions use whatever is the "current material" set up right now (see Material.SetPass). The material controls how the rendering is done (blending, textures, etc.), so unless you explicitly set it to something before using GL draw functions, the material can happen to be anything. Also, if you call any other drawing commands from inside GL drawing code, they can set material to something else, so make sure it's under control as well.

GL drawing commands execute immediately. That means if you call them in Update(), they will be executed before the camera is rendered (and the camera will most likely clear the screen, making the GL drawing not visible).

The usual place to call GL drawing is most often in OnPostRender() from a script attached to a camera, or inside an image effect function (OnRenderImage).

_Note:_ The High Definition Render Pipeline (HDRP) and the Universal Render Pipeline (URP) do not support OnPostRender. Instead, use endCameraRendering or endFrameRendering.

using UnityEngine;

public class ExampleClass : MonoBehaviour
{
    // When added to an object, draws colored rays from the
    // transform position.
    public int lineCount = 100;
    public float radius = 3.0f;

    static Material lineMaterial;
    static void CreateLineMaterial()
    {
        if (!lineMaterial)
        {
            // Unity has a built-in shader that is useful for drawing
            // simple colored things.
            Shader shader = Shader.Find("Hidden/Internal-Colored");
            lineMaterial = new Material(shader);
            lineMaterial.hideFlags = HideFlags.HideAndDontSave;
            // Turn on alpha blending
            lineMaterial.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);
            lineMaterial.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);
            // Turn backface culling off
            lineMaterial.SetInt("_Cull", (int)UnityEngine.Rendering.CullMode.Off);
            // Turn off depth writes
            lineMaterial.SetInt("_ZWrite", 0);
        }
    }

    // Will be called after all regular rendering is done
    public void OnRenderObject()
    {
        CreateLineMaterial();
        // Apply the line material
        lineMaterial.SetPass(0);

        GL.PushMatrix();
        // Set transformation matrix for drawing to
        // match our transform
        GL.MultMatrix(transform.localToWorldMatrix);

        // Draw lines
        GL.Begin(GL.LINES);
        for (int i = 0; i < lineCount; ++i)
        {
            float a = i / (float)lineCount;
            float angle = a * Mathf.PI * 2;
            // Vertex colors change from red to green
            GL.Color(new Color(a, 1 - a, 0, 0.8F));
            // One vertex at transform position
            GL.Vertex3(0, 0, 0);
            // Another vertex at edge of circle
            GL.Vertex3(Mathf.Cos(angle) * radius, Mathf.Sin(angle) * radius, 0);
        }
        GL.End();
        GL.PopMatrix();
    }
}

**注:** このクラスはラインやトライアングルの組を描画する必要があるときにはほぼ常に使用し、メッシュには使わないでください。 予想外の動作をさけるため、基本的な使用方法は:

using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour
{
    void OnPostRender()
    {
        // Set your materials
        GL.PushMatrix();
        // yourMaterial.SetPass( );
        // Draw your stuff
        GL.PopMatrix();
    }
}

"// 何かを描画" において SetPass() を事前に宣言したマテリアルで使用し、描画のために使用すべきです。 SetPass を呼び出ししない場合、マテリアルはランダムに選ばれる（過去に使用されたたものの中から）ため必ず呼び出すべきです。

Static 変数

Static 関数