我刚刚开始在我的应用程序中使用 opengl,而且我很好 =) 但我最近遇到了障碍,因为我一直在尝试找出用户输入的方法。我决定从一个简单的过程开始,在您触摸屏幕的位置在屏幕上绘制一个正方形。不幸的是,该应用程序似乎没有注册输入。
这是我的代码:
该应用程序打开此活动>>
import android.app.Activity;
import android.opengl.GLSurfaceView;
import android.os.Bundle;
import android.view.Window;
import android.view.WindowManager;
public class Practice extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
GLSurfaceView view = new GLSurfaceView (this);
view.setRenderer(new GLSurfaceRenderer());
setContentView(view);
}
}
这会初始化一个全屏 SurfaceView。
接下来是渲染器
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.opengl.GLU;
import android.opengl.GLSurfaceView.Renderer;
import android.view.MotionEvent;
public class GLSurfaceRenderer implements Renderer{
private FlatColoredSquare Square;
private float setx = 0;
private float sety = 0;
public GLSurfaceRenderer () {
Square = new FlatColoredSquare();
}
public boolean onTouchEvent (MotionEvent event, GL10 gl){
if (event.getAction() == MotionEvent.ACTION_UP){
gl.glPushMatrix();
gl.glTranslatef(event.getX(), event.getY(), -10);
Square.draw(gl);
gl.glPopMatrix();
}
return true;
}
@Override
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT |
GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity();
gl.glPushMatrix();
gl.glTranslatef(setx, sety, -10);
Square.draw(gl);
gl.glPopMatrix();
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluPerspective(gl, 45.0f, (float)width / (float)height, 0.1f, 100f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glClearDepthf(1.0f);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
}
}
如您所见,有一个 onTouchEvent 获取事件的坐标并将它们设置为顶部的浮点数。然后 draw 方法使用这些坐标来设置正方形的位置。我不认为这里的 draw 方法更新到足以重新绘制正方形。如何设置draw方法来更新正方形onTouch?除了尝试将正方形设置为从 onTouch 方法内部绘制外,我还将其留空,例如:
public boolean onTouchEvent (MotionEvent event){
if (event.getAction() == MotionEvent.ACTION_UP){
setx = event.getX();
sety = event.getY();
}
return true;
}
这两个都返回相同的结果=(所以我做 onTouchEvent 错了吗?还是我必须强制 draw 方法以某种方式更新?我将如何正确实现呢?
感谢您的时间
编辑:
通过将方法移至 Practice 类,设法获取注册 onTouchEvent 的代码。
编辑:进行了更多改进,代码现在在一定程度上可以正常工作,但不是在所需位置重新绘制正方形,而是得到一个空白的清除屏幕。
这里是编辑练习
import android.app.Activity;
import android.opengl.GLSurfaceView;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.Window;
import android.view.WindowManager;
import android.app.ui.GLSurfaceRenderer;
public class Practice extends Activity {
private GLSurfaceRenderer glSurfaceRenderer;
public static float setx;
public static float sety;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
GLSurfaceView view = new GLSurfaceView (this);
view.setRenderer(glSurfaceRenderer = new GLSurfaceRenderer());
setContentView(view);
}
@Override
public synchronized boolean onTouchEvent (MotionEvent event){
if (event.getAction() == MotionEvent.ACTION_UP){
glSurfaceRenderer.randomMethod(event);
}
return true;
}
}
并编辑了渲染器类
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.opengles.GL10;
import android.opengl.GLU;
import android.opengl.GLSurfaceView.Renderer;
import android.view.MotionEvent;
public class GLSurfaceRenderer implements Renderer{
private float setx;
private float sety;
private FlatColoredSquare square;
public GLSurfaceRenderer () {
square = new FlatColoredSquare();
}
public synchronized void randomMethod(MotionEvent event){
setx = event.getX();
sety = event.getY();
}
@Override
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT |
GL10.GL_DEPTH_BUFFER_BIT);
gl.glLoadIdentity();
gl.glPushMatrix();
gl.glTranslatef(setx, sety, -10);
square.draw(gl);
gl.glPopMatrix();
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluPerspective(gl, 45.0f, (float)width / (float)height, 0.1f, 100f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glClearDepthf(1.0f);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
}
}
有任何想法吗?这是方码
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;
import javax.microedition.khronos.opengles.GL10;
public class FlatColoredSquare {
private float vertices[] = {
-1.0f, 1.0f, 0.0f,
-1.0f, -1.0f, 0.0f,
1.0f, -1.0f, 0.0f,
1.0f, 1.0f, 0.0f
};
private short indices[] = {0, 1, 2, 0, 2, 3,};
private FloatBuffer vertexBuffer;
private ShortBuffer indexBuffer;
public FlatColoredSquare() {
ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length*4);
vbb.order(ByteOrder.nativeOrder());
vertexBuffer = vbb.asFloatBuffer();
vertexBuffer.put(vertices);
vertexBuffer.position(0);
ByteBuffer ibb = ByteBuffer.allocateDirect(indices.length*2);
ibb.order(ByteOrder.nativeOrder());
indexBuffer = ibb.asShortBuffer();
indexBuffer.put(indices);
indexBuffer.position(0);
}
public void draw(GL10 gl) {
gl.glColor4f(0.0f, 1.0f, 0.0f, 0.0f);
gl.glFrontFace(GL10.GL_CCW);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glCullFace(GL10.GL_BACK);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glDrawElements(GL10.GL_TRIANGLES, indices.length,
GL10.GL_UNSIGNED_SHORT, indexBuffer);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisable(GL10.GL_CULL_FACE);
}
}