我有一个从数据库接收信息的应用程序，用于将2D位图可视化到GLSurfaceView上。收到的信息将决定位图的x位置，以及要使用的位图图像（我的res文件夹中有4个不同的位图可供选择）。
以下是正在使用的三个类。 Activity通过将ArrayList传递给GLLayer类来设置需要绘制的Shapes对象。此ArrayList通过另一个setList方法传递给ShapeStorage类的实例。这个班负责收到它们时的绘图。
我遇到的问题如下。假设我收到一个对象（让我们说它是位于x = 1处的正方形）。一段时间过去了，我收到另一个形状（这次，它是一个三角形，它位于x = -1）。但是，当这个新形状出现在屏幕上时，旧位图的外观会变为三角形，而新的位图会变成正方形。换句话说，对象本身处于它们应该处于的正确位置，但与它们相关联的位图已经改变。有谁知道这可能是什么原因造成的？我仍然是OpenGL-ES的新手，虽然这段代码看起来很复杂，但它只涉及为View设置一堆不同的属性。请帮帮我，StackOverflow！你是我唯一的希望。
public class GLLayer extends GLSurfaceView implements Renderer {
int onDrawFrameCounter=1;
int[] cameraTexture;
byte[] glCameraFrame=new byte[256*256]; //size of a texture must be a power of 2
private Context context;
FloatBuffer cubeBuff;
FloatBuffer texBuff;
ShapeStorage shapes;
ArrayList<Shapes> shapereceptionbuffer;
public GLLayer(Context c) {
super(c);
this.context=c;
//Initiate our stars class with the number of stars
shapes = new ShapeStorage();
shapereceptionbuffer=new ArrayList<Shapes>();
this.setEGLConfigChooser(5, 6, 5, 8, 16, 0);
this.setRenderer(this); //set the following class as a GLSurfaceView renderer
this.getHolder().setFormat(PixelFormat.TRANSPARENT); //makes the GLSurfaceView translucent
}
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
try {
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
gl.glShadeModel(GL10.GL_SMOOTH); //Enable Smooth Shading
gl.glEnable(GL10.GL_TEXTURE_2D); //Enable Texture Mapping
gl.glEnable(GL10.GL_BLEND); //Enable blending
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.0f); //Black Background
gl.glClearDepthf(1.0f); //Depth Buffer Setup
gl.glDisable(GL10.GL_DEPTH_TEST); //Disable depth test
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE); //Set The Blending Function For Translucency
shapes.setTextures(gl,context);
} catch (Exception e) {
// TODO Auto-generated catch block
Log.d("Created",e.getMessage());
}
}//end of surfacecreated
public void setList(ArrayList<Shapes> receivedList){
synchronized(this.shapereceptionbuffer){
shapereceptionbuffer=receivedList;
}
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
try {
if(height == 0) { //Prevent A Divide By Zero By
height = 1; //Making Height Equal One
}
gl.glViewport(0, 0, width, height);//specifies transformation from normalized device coordinates to window coordinates
float ratio = (float) width / height;
gl.glMatrixMode(GL11.GL_PROJECTION); //Select The Projection Matrix
gl.glLoadIdentity();//Reset The Projection Matrix
GLU.gluPerspective(gl, 45.0f, ratio, 0.1f, 100.0f);
gl.glMatrixMode(GL11.GL_MODELVIEW);//Select The Modelview Matrix
gl.glLoadIdentity();//Reset The Modelview Matrix
} catch (Exception e) {
// TODO Auto-generated catch block
Log.d("Changed",e.getMessage());
}
//GLU.gluLookAt(gl, 0, 0, 4.2f, 0, 0, 0, 0, 1, 0);//eye-point location, center of the scene and an UP vector
}//end of surfacechanged
public void onDrawFrame(GL10 gl) {
try {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT); //Clear Screen And Depth Buffer
Log.d("Buffer Size", String.valueOf(shapereceptionbuffer.size()));
synchronized(this.shapereceptionbuffer){
shapes.setShapes(shapereceptionbuffer);
shapes.draw(gl, this.context);
}
} catch (Exception e) {
Log.d("Draw",e.getMessage());
}
}//end of ondrawframe
}
此类负责绘制从外部数据库接收的每个形状。
/**
* This class contains, loads, initiates textures and draws our Shapes
*/
public class ShapeStorage {
private ArrayList<Shapes> shapestoragebuffer;
private Random rand = new Random(); // Initiate Random for random values of
// stars
/** Our texture pointer */
private int[] textures = new int[4];
/**
* Constructor for our holder
*/
public ShapeStorage() {
shapestoragebuffer = new ArrayList<Shapes>();
}
public void setShapes(ArrayList<Shapes> receivedlist) {
shapestoragebuffer = receivedList;
}
public void setupTextures(GL10 gl, Context context) {
// Get the texture from the Android resource directory
InputStream is = null;
gl.glGenTextures(4, textures, 0);
for (int i = 2; i < 6; i++) {
switch (i) {
case 2:
is = context.getResources().openRawResource(R.drawable.square);
break;
case 3:
is = context.getResources().openRawResource(R.drawable.circle);
break;
case 4:
is = context.getResources().openRawResource(R.drawable.hexagon);
break;
case 5:
is = context.getResources()
.openRawResource(R.drawable.triangle);
break;
}
Bitmap bitmap = null;
try {
// BitmapFactory is an Android graphics utility for images
bitmap = BitmapFactory.decodeStream(is);
} finally {
// Always clear and close
try {
is.close();
is = null;
} catch (IOException e) {
}
}
// Generate the texture pointer
// Create Linear Filtered Texture and bind it to texture
GLUtils.texImage2D(GL11.GL_TEXTURE_2D, 0, bitmap, 0);
gl.glBindTexture(GL11.GL_TEXTURE_2D, textures[i - 2]);
gl.glTexParameterf(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MAG_FILTER,
GL11.GL_LINEAR);
gl.glTexParameterf(GL11.GL_TEXTURE_2D, GL11.GL_TEXTURE_MIN_FILTER,
GL11.GL_LINEAR);
// Clean up
bitmap.recycle();
}
}
/**
* The drawing function.
*
* @param gl
* - The GL Context
* @param twinkle
* - Twinkle on or off
*/
public void draw(GL10 gl, Context context) {
// Bind the icon texture for all Shapes
for (int loop = 0; loop < shapestoragebuffer.size(); loop++) {
// Recover the current star into an object
Shapes shape = shapestoragebuffer.get(loop);
gl.glLoadIdentity(); // Reset The Current Modelview Matrix
// gl.glRotatef(180.0f, -1.0f, 0.0f, 0.0f);
float x = shape.get_Offset_from_center();
gl.glTranslatef(x, 0.0f, -40.0f);
// Draw
switch (victim.getType()) {
// green
case 2:
shape.draw(gl, textures[0]);
break;
// red
case 3:
shape.draw(gl, textures[1]);
break;
// yellow
case 4:
shape.draw(gl, textures[2]);
break;
case 5:
shape.draw(gl, textures[3]);
break;
}
}
}
}
这是定义绘制到GLSurfaceView的每个对象的类;每个正在绘制的形状。
public class Shapes {
private int _Offset_from_center;
private int type;
Context c;
/** The buffer holding the vertices */
private FloatBuffer vertexBuffer;
/** The buffer holding the texture coordinates */
private FloatBuffer textureBuffer;
/** The initial vertex definition */
private float vertices[] = {
-1.0f, -1.0f, 0.0f, //Bottom Left
1.0f, -1.0f, 0.0f, //Bottom Right
-1.0f, 1.0f, 0.0f, //Top Left
1.0f, 1.0f, 0.0f //Top Right
};
/** The initial texture coordinates (u, v) */
private float texture[] = {
0.0f, 0.0f,
1.0f, 0.0f,
0.0f, 1.0f,
1.0f, 1.0f,
};
public Shapes() {
//
ByteBuffer byteBuf = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
vertexBuffer = byteBuf.asFloatBuffer();
vertexBuffer.put(vertices);
vertexBuffer.position(0);
//
byteBuf = ByteBuffer.allocateDirect(texture.length * 4);
byteBuf.order(ByteOrder.nativeOrder());
textureBuffer = byteBuf.asFloatBuffer();
textureBuffer.put(texture);
textureBuffer.position(0);
}
public int get_Offset_from_center() {
return _Offset_from_center;
}
public void set_Offset_from_center(int _Offset_from_center) {
this._Offset_from_center = _Offset_from_center;
}
public int getType() {
return type;
}
public void setType(int type) {
this.type = type;
}
/**
* The object own drawing function.
* Called from the renderer to redraw this instance
* with possible changes in values.
*
* @param gl - The GL Context
*/
public void draw(GL10 gl,int texture) {
gl.glBindTexture(GL11.GL_TEXTURE_2D, texture);
//Enable the vertex, texture and normal state
gl.glEnableClientState(GL11.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
//Point to our buffers
gl.glVertexPointer(3, GL11.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL11.GL_FLOAT, 0, textureBuffer);
//Draw the vertices as triangle strip
gl.glDrawArrays(GL11.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL11.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL11.GL_TEXTURE_COORD_ARRAY);
}
}
答案 0 :(得分：4)
你正在用纹理做一些非常奇怪的事情。为什么要为每一帧上传每个形状的纹理图像数据，为什么在渲染形状之后 ？
以下是OpenGL中常用的纹理流程：
在应用初始化时间：
glGenTextures生成纹理ID。glBindTexture将该ID设为当前纹理。texImage2D或类似内容上传图片数据。然后，每次你需要用纹理渲染东西时：
glBindTexture绑定纹理。我建议的是：
当您开始活动时（根据Android OpenGL的工作原理，从onCreate或onResume间接调用）：
textures设为5个元素的数组，并将5传递给glGenTextures texImage2D上传您的图片，就像您一样。然后，当你真的需要画一个形状时：
glBindTexture。texImage2D进行任何调用。glDrawArrays以使用glBindTexture绘制您选择的形状。另请注意，所有形状都可以共享相同的顶点和纹理缓冲区，因为它们的内容相同;这只是一种效率的事情。