OpenGL slower than Canvas
- by VanDir
Up to 3 days ago I used a Canvas in a SurfaceView to do all the graphics operations but now I switched to OpenGL because my game went from 60FPS to 30/45 with the increase of the sprites in some levels. However, I find myself disappointed because OpenGL now reaches around 40/50 FPS at all levels. Surely (I hope) I'm doing something wrong. How can I increase the performance at stable 60FPS? My game is pretty simple and I can not believe that it is impossible to reach them.
I use 2D sprite texture applied to a square for all the objects. I use a transparent GLSurfaceView, the real background is applied in a ImageView behind the GLSurfaceView.
Some code
public MyGLSurfaceView(Context context, AttributeSet attrs) {
super(context);
setZOrderOnTop(true);
setEGLConfigChooser(8, 8, 8, 8, 0, 0);
getHolder().setFormat(PixelFormat.RGBA_8888);
mRenderer = new ClearRenderer(getContext());
setRenderer(mRenderer);
setLongClickable(true);
setFocusable(true);
}
public void onSurfaceCreated(final GL10 gl, EGLConfig config) {
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glDisable(GL10.GL_DEPTH_TEST);
gl.glDepthMask(false);
gl.glEnable(GL10.GL_ALPHA_TEST);
gl.glAlphaFunc(GL10.GL_GREATER, 0);
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_ONE, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
}
public void onSurfaceChanged(GL10 gl, int width, int height) {
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
gl.glOrthof(0, width, height, 0, -1f, 1f);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
// Draw all the graphic object.
for (byte i = 0; i < mGame.numberOfObjects(); i++){
mGame.getObject(i).draw(gl);
}
// Disable the client state before leaving
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
mGame.getObject(i).draw(gl) is for all the objects like this:
/* HERE there is always a translatef and scalef transformation and sometimes rotatef */
gl.glBindTexture(GL10.GL_TEXTURE_2D, mTexPointer[0]);
// Point to our vertex buffer
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, mVertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, mTextureBuffer);
// Draw the vertices as triangle strip
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, mVertices.length / 3);
EDIT:
After some test it seems to be due to the transparent GLSurfaceView. If I delete this line of code:
setEGLConfigChooser(8, 8, 8, 8, 0, 0);
the background becomes all black but I reach 60 fps. What can I do?
