Android - 使用 openGL ES 绘制 3D 然后 2D

Posted 2023-03-07

【中文标题】Android - 使用 openGL ES 绘制 3D 然后 2D

【英文标题】：Android - Draw 3D then 2D with openGL ES

【发布时间】：2010-09-23 07:39:51

【问题描述】：

在 openGL ES 中绘制一些 3d 内容后如何绘制 HUD（文本或位图）？？

我试过这个：

private void switchTo2D(GL10 gl)  
  gl.glDisable(GL10.GL_DEPTH_TEST);  
  gl.glMatrixMode(GL10.GL_PROJECTION);  
  gl.glPushMatrix();  
  gl.glLoadIdentity();  

  gl.glMatrixMode( GL10.GL_PROJECTION );  
  gl.glLoadIdentity();  
  GLU.gluOrtho2D( gl, 0, getViewportWidth(), 0, getViewportHeight() );

  gl.glMatrixMode(GL10.GL_MODELVIEW);  
  gl.glLoadIdentity();  

有人知道如何在不破坏场景的情况下从透视切换到正交？？

【问题讨论】：

你试过这个吗？它奏效了吗？为什么没有工作？

不，如果我尝试绘制 2D 东西，它看起来像这样：dl.dropbox.com/u/2024237/device.png 但当我不尝试切换到 Ortho 时，它看起来像这样：dl.dropbox.com/u/2024237/device2.png 更多来源：pastebin.com/HVhVYV8k

【参考方案1】：

我找到了解决方案，但我忘记发布了 :) 抱歉

package at.bartinger.opengl;

import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;

import android.content.Context;
import android.opengl.GLSurfaceView;
import android.opengl.GLU;
import android.util.AttributeSet;

public class GLGameView extends GLSurfaceView implements GLSurfaceView.Renderer


public GLGameView(Context context) 
    super(context);
    setRenderer(this);


public GLGameView(Context context, AttributeSet attrs) 
    super(context, attrs);
    // TODO Auto-generated constructor stub


@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) 
    init(gl);


@Override
public void onDrawFrame(GL10 gl) 

    //Standard
    gl.glClear( GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT );
    gl.glViewport( 0, 0, getWidth(), getHeight() );

    gl.glDisable( GL10.GL_DITHER );
    gl.glEnable( GL10.GL_DEPTH_TEST );
    gl.glEnable( GL10.GL_CULL_FACE );

    //Set 3D
    gl.glMatrixMode( GL10.GL_PROJECTION );
    gl.glLoadIdentity();
    gluPerspective( gl);    



    draw3D(gl);


    gl.glDisable( GL10.GL_CULL_FACE );
    gl.glDisable( GL10.GL_DEPTH_TEST );

    //Set 2D
    gl.glMatrixMode( GL10.GL_PROJECTION );
    gl.glLoadIdentity();
    gluOrtho2D(gl);
    gl.glMatrixMode( GL10.GL_MODELVIEW );
    gl.glLoadIdentity();


    draw2D(gl);



@Override
public void onSurfaceChanged(GL10 gl, int width, int height) 



public void init(GL10 gl)

public void draw2D(GL10 gl);

public void draw3D(GL10 gl);

/**
 * Sets the projection to the ortho matrix
 */
public void gluOrtho2D(GL10 gl)
    gl.glMatrixMode( GL10.GL_PROJECTION );
    gl.glLoadIdentity();
    GLU.gluOrtho2D( gl, 0, getWidth(), 0, getHeight() );


/**
 * Sets the projection to the perspective matrix
 */
public void gluPerspective(GL10 gl)
    gl.glMatrixMode( GL10.GL_PROJECTION );
    gl.glLoadIdentity();
    float aspectRatio = (float)getWidth() / getHeight();
    GLU.gluPerspective( gl, 67, aspectRatio, 1, 100 );


/**
 * Sets the projection to the perspective matrix
 */
public void gluPerspective(GL10 gl, float near, float far)
    gl.glMatrixMode( GL10.GL_PROJECTION );
    gl.glLoadIdentity();
    float aspectRatio = (float)getWidth() / getHeight();
    GLU.gluPerspective( gl, 67, aspectRatio, near, far );


/**
 * Sets the projection to the model view matrix
 */
public void gluLookAt(GL10 gl, 
        float positionX, float positionY, float positionZ,
        float zentrumX, float zentrumY, float zentrumZ,
        float upX, float upY, float upZ )

    gl.glMatrixMode( GL10.GL_MODELVIEW );
    gl.glLoadIdentity();
    GLU.gluLookAt( gl,positionX, positionY, positionZ, zentrumX, zentrumY, zentrumZ, upX, upY, upZ );