以下代码在较旧的 Android 版本上完美运行，但仅在较新版本上显示黑屏（我猜是 4.2 及更高版本）。我对 OpenGL 很陌生，我曾经使用 Canvas/SurfaceView，但现在我需要 GLSurfaceView 来获得性能，所以我从这里和那里获取了一些代码，但并不完全知道它的作用。我没有开始一个全新的项目，我只是将我的一些“Canvas-Code”重写为 GLSurfaceView 循环。这就是为什么它看起来很奇怪而且效率低下的原因。
代码说明：“Sprite”类包含一个位图、xPos 和 yPos。在“defineStuff();”中 我将一些不同的“精灵”附加到列表中，GLSurfaceView 从列表中绘制所有内容。这不是全部代码，我删除了很多以使其更清晰。
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN); //so its Fullscreen
defineStuff();
glSurfaceView = new GLSurfaceView(this);
glSurfaceView.setRenderer(new GlRenderer());
glSurfaceView.setOnTouchListener(this);
setContentView(glSurfaceView);
}
精灵类：
public class Sprite {
private FloatBuffer vertexBuffer; // buffer holding the vertices
private FloatBuffer textureBuffer; // buffer holding the texture coordinates
private float texture[];
private float vertices[];
public Bitmap bmp;
public boolean visible;
public String name;
public float posX;
public float posY;
public Sprite(String name, Bitmap bitmap, float posX, float posY, boolean visible) {
this.name = name;
this.visible = visible;
setBuffers(bitmap, posX, posY);
}
public void setBuffers(Bitmap bitmap, float posX, float posY) {
bmp = bitmap;
}
this.posX = posX;
this.posY = posY;
float tempVertices[] = {
posX, posY + bitmap.getHeight(), 0.0f, // V1 - bottom left
posX, posY, 0.0f, // V2 - top left
posX + bitmap.getWidth(), posY + bitmap.getHeight(), 0.0f, // V3 - bottom right
posX + bitmap.getWidth(), posY, 0.0f // V4 - top right
};
vertices = new float[tempVertices.length];
System.arraycopy(tempVertices, 0, vertices, 0, tempVertices.length);
// a float has 4 bytes so we allocate for each coordinate 4 bytes
ByteBuffer byteBuffer = ByteBuffer.allocateDirect(vertices.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
// allocates the memory from the byte buffer
vertexBuffer = byteBuffer.asFloatBuffer();
// fill the vertexBuffer with the vertices
vertexBuffer.put(vertices);
// set the cursor position to the beginning of the buffer
vertexBuffer.position(0);
float tempTexture[] = {
// Mapping coordinates for the vertices
0.0f, 1.0f, // top left (V2)
0.0f, 0.0f, // bottom left (V1)
1.0f, 1.0f, // top right (V4)
1.0f, 0.0f // bottom right (V3)
};
texture = new float[tempTexture.length];
System.arraycopy(tempTexture, 0, texture, 0, tempTexture.length);
byteBuffer = ByteBuffer.allocateDirect(texture.length * 4);
byteBuffer.order(ByteOrder.nativeOrder());
textureBuffer = byteBuffer.asFloatBuffer();
textureBuffer.put(texture);
textureBuffer.position(0);
}
/** The texture pointer */
private int[] textures = new int[1];
public void loadGLTexture(GL10 gl) { // every Sprite has to be loaded before being drawn
// generate one texture pointer
gl.glGenTextures(1, textures, 0);
// ...and bind it to our array
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
// create nearest filtered texture
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER, GL10.GL_NEAREST);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER, GL10.GL_LINEAR);
// Use Android GLUtils to specify a two-dimensional texture image from our bitmap
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bmp, 0);
}
public void draw(GL10 gl, float interpolation) {
gl.glPushMatrix();
gl.glTranslatef (speedInX * interpolation, speedInY * interpolation, 0f);
// bind the previously generated texture
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
// Point to our buffers
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Set the face rotation
gl.glFrontFace(GL10.GL_CW);
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
//Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glPopMatrix();
}
}
我的渲染器：
public class GlRenderer implements Renderer {
@Override
public void onDrawFrame(GL10 gl) {
// clear Screen and Depth Buffer
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
// Reset the Modelview Matrix
gl.glLoadIdentity();
// Drawing
gl.glTranslatef(0.0f, 0.0f, -5.0f); // move 5 units INTO the screen
// is the same as moving the camera 5 units away
updateLogic(gl); //there was very much code around this but I removed it to make it more clear
float interpolation = (float) (SystemClock.uptimeMillis() + SKIP_TICKS - nextGameTick) / SKIP_TICKS;
spriteList.toFirst();
while (spriteList.getObject() != null) {
((Sprite) spriteList.getObject()).draw(gl, interpolation);
spriteList.next();
}
}
@Override
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION); // or some matrix uniform if using shaders
gl.glLoadIdentity();
gl.glOrthof(0, width, height, 0, -1, 1); // this will allow to pass vertices in 'canvas pixel' coordinates
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
@Override
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glDisable(GL10.GL_DITHER);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_FASTEST);
gl.glEnable(GL10.GL_TEXTURE_2D); //Enable Texture Mapping ( NEW )
gl.glShadeModel(GL10.GL_SMOOTH); //Enable Smooth Shading
gl.glClearColor(0.0f, 0.0f, 0.0f, 0.5f); //Set Background
gl.glClearDepthf(1.0f); //Depth Buffer Setup
gl.glEnable(GL10.GL_DEPTH_TEST); //Enables Depth Testing
gl.glDepthFunc(GL10.GL_LEQUAL); //The Type Of Depth Testing To Do
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA); // So alpha works, but it still doesnt work everytime :)
spriteList.toFirst();
while (spriteList.getObject() != null) {
((Sprite) spriteList.getObject()).loadGLTexture(gl);
spriteList.next();
}
}
}