OpenGL ESの勉強を始める
ApiDemosのGLSurfaceViewを１クラスにまとめてみた。
public class Sample extends Activity {
public static class MyView extends SurfaceView implements
SurfaceHolder.Callback {
public MyView(Context context) {
super(context);
SurfaceHolder mHolder = getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_GPU);
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
EGL10 mEgl = (EGL10) EGLContext.getEGL();
EGLDisplay mEglDisplay = mEgl
.eglGetDisplay(EGL10.EGL_DEFAULT_DISPLAY);
int[] version = new int[2];
mEgl.eglInitialize(mEglDisplay, version);
EGLConfig[] configs = new EGLConfig[1];
int[] num_config = new int[1];
int[] configSpec = { EGL10.EGL_DEPTH_SIZE, 16, EGL10.EGL_NONE };
mEgl.eglChooseConfig(mEglDisplay, configSpec, configs, 1,
num_config);
EGLConfig mEglConfig = configs[0];
/*
* Create an OpenGL ES context. This must be done only once, an
* OpenGL context is a somewhat heavy object.
*/
EGLContext mEglContext = mEgl.eglCreateContext(mEglDisplay,
mEglConfig, EGL10.EGL_NO_CONTEXT, null);
EGLSurface
/*
* Create an EGL surface we can render into.
*/
mEglSurface = mEgl.eglCreateWindowSurface(mEglDisplay, mEglConfig,
holder, null);
/*
* Before we can issue GL commands, we need to make sure the context
* is current and bound to a surface.
*/
mEgl.eglMakeCurrent(mEglDisplay, mEglSurface, mEglSurface,
mEglContext);
GL10 gl = (GL10) mEglContext.getGL();
gl.glViewport(0, 0, getWidth(), getHeight());
/*
* Set our projection matrix. This doesn't have to be done each time
* we draw, but usually a new projection needs to be set when the
* viewport is resized.
*/
float ratio = (float) getWidth() / getHeight();
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glFrustumf(-ratio, ratio, -1, 1, 1, 10);
/*
* Usually, the first thing one might want to do is to clear the
* screen. The most efficient way of doing this is to use glClear().
*/
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
/*
* Now we're ready to draw some 3D objects
*/
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
gl.glTranslatef(0, 0, -3.0f);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
// ---------
int one = 0x10000;
int vertices[] = { -one, -one, -one, one, -one, -one, one, one,
-one, -one, one, -one, -one, -one, one, one, -one, one,
one, one, one, -one, one, one, };
int colors[] = { 0, 0, 0, one, one, 0, 0, one, one, one, 0, one, 0,
one, 0, one, 0, 0, one, one, one, 0, one, one, one, one,
one, one, 0, one, one, one, };
byte indices[] = { 0, 4, 5, 0, 5, 1, 1, 5, 6, 1, 6, 2, 2, 6, 7, 2,
7, 3, 3, 7, 4, 3, 4, 0, 4, 7, 6, 4, 6, 5, 3, 0, 1, 3, 1, 2 };
IntBuffer mVertexBuffer;
IntBuffer mColorBuffer;
ByteBuffer mIndexBuffer;
// Buffers to be passed to gl*Pointer() functions
// must be direct, i.e., they must be placed on the
// native heap where the garbage collector cannot
// move them.
//
// Buffers with multi-byte datatypes (e.g., short, int, float)
// must have their byte order set to native order
ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4);
vbb.order(ByteOrder.nativeOrder());
mVertexBuffer = vbb.asIntBuffer();
mVertexBuffer.put(vertices);
mVertexBuffer.position(0);
ByteBuffer cbb = ByteBuffer.allocateDirect(colors.length * 4);
cbb.order(ByteOrder.nativeOrder());
mColorBuffer = cbb.asIntBuffer();
mColorBuffer.put(colors);
mColorBuffer.position(0);
mIndexBuffer = ByteBuffer.allocateDirect(indices.length);
mIndexBuffer.put(indices);
mIndexBuffer.position(0);
gl.glFrontFace(gl.GL_CW);
gl.glVertexPointer(3, gl.GL_FIXED, 0, mVertexBuffer);
gl.glColorPointer(4, gl.GL_FIXED, 0, mColorBuffer);
gl.glDrawElements(gl.GL_TRIANGLES, 36, gl.GL_UNSIGNED_BYTE,
mIndexBuffer);
mEgl.eglSwapBuffers(mEglDisplay, mEglSurface);
if (mEglSurface != null) {
mEgl.eglMakeCurrent(mEglDisplay, EGL10.EGL_NO_SURFACE,
EGL10.EGL_NO_SURFACE, EGL10.EGL_NO_CONTEXT);
mEgl.eglDestroySurface(mEglDisplay, mEglSurface);
mEglSurface = null;
}
if (mEglContext != null) {
mEgl.eglDestroyContext(mEglDisplay, mEglContext);
mEglContext = null;
}
if (mEglDisplay != null) {
mEgl.eglTerminate(mEglDisplay);
mEglDisplay = null;
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
}
private MyView mGLSurfaceView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mGLSurfaceView = new MyView(this);
setContentView(mGLSurfaceView);
}
@Override
protected void onPause() {
super.onPause();
}
@Override
protected void onResume() {
super.onResume();
}
}
