What is wrong with using the depth buffer? OpenGL ES 2.0

Question

I am using this code:

context = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];

    if (!context || ![EAGLContext setCurrentContext:context] || ![self loadShaders])
    {
        [self release];
        return nil;
    }

    glGenFramebuffers(1, &defaultFramebuffer);
    glGenRenderbuffers(1, &colorRenderbuffer);
    glGenRenderbuffers(1, &depthRenderbuffer);

    glBindFramebuffer(GL_FRAMEBUFFER, defaultFramebuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, colorRenderbuffer);
    glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);

    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, colorRenderbuffer);
    glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);

    glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

But when I launch the application, do I see a purple screen? What is wrong with this code?

Answer 1

I don’t see where you are binding your color rendering buffer to the CAEAGLLayer on which it should be displayed (although this may happen later), and I don’t see you doing depth testing. In addition, if I'm not mistaken, you need to bind the color rendering glFramebufferRenderbuffer()buffer , call for this, then bind the depth of the renderbuffer and call it again.

Below is the code that I used to configure a similar display in OpenGL ES 2.0:

glEnable(GL_DEPTH_TEST);

glGenFramebuffers(1, &viewFramebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, viewFramebuffer);

glGenRenderbuffers(1, &viewRenderbuffer);
glBindRenderbuffer(GL_RENDERBUFFER, viewRenderbuffer);

[context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer];

glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_WIDTH, &backingWidth);
glGetRenderbufferParameteriv(GL_RENDERBUFFER, GL_RENDERBUFFER_HEIGHT, &backingHeight);

glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, viewRenderbuffer);

glGenRenderbuffers(1, &depthRenderbuffer);
glBindRenderbuffer(GL_RENDERBUFFER, depthRenderbuffer);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT16, backingWidth, backingHeight);
glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthRenderbuffer);

if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) 
{
    NSLog(@"Failure with framebuffer generation");
    return NO;
}

.

Answer 2

, , , , . , , :

glGenBuffers(1, &_colorRenderBuffer);

:

glGenRenderbuffers(1, &_colorRenderBuffer);

: .