Viewing depth buffer in OpenGL - c++

Question

I am having trouble viewing depth rendered to a texture. I can view it when I render depth as RGB to texture, but when I try to render depth only I get only black. I have searched for many hours and implemented fixes from other similar questions, but to no avail. I've disabled GL_TEXTURE_COMPARE_MODE, added glDrawBuffer(GL_NONE) and glReadBuffer(GL_NONE).
I'm running on OSX 10.9 and OpenGL 4.1. I've removed gl error checking from the pasted code for conciseness.
The setup for the depth FBO/texture is this:
glGenFramebuffers(1, &FramebufferName);
glBindFramebuffer(GL_FRAMEBUFFER, FramebufferName);
glGenTextures(1, &renderedTexture);
glBindTexture(GL_TEXTURE_2D, renderedTexture);
glTexImage2D(GL_TEXTURE_2D, 0,
GL_DEPTH_COMPONENT,
fbWidth,
fbHeight,
0,
GL_DEPTH_COMPONENT,
GL_FLOAT,
0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_FUNC, GL_LEQUAL);
// glTexParameteri (GL_TEXTURE_2D, GL_DEPTH_TEXTURE_MODE, GL_INTENSITY);
// glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_COMPARE_R_TO_TEXTURE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_COMPARE_MODE, GL_NONE);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D, renderedTexture, 0);
glDrawBuffer(GL_NONE);
glReadBuffer(GL_NONE);
if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
assert(false && "framebuffer NOT OK");
depth fragment - I can see depth when rendering RGB
#version 150 core
#if RENDER_RGB
out vec4 outColor;
void main(){
vec3 color = gl_FragCoord.z);
outColor = vec4(color, 1.0);
}
#else
void main(){
gl_FragDepth = gl_FragCoord.z;
}
#endif
Reading back the depth texture, I am using this fragment shader:
#version 150 core
in vec2 UV;
uniform sampler2D renderedTexture;
out vec4 outColor;
void main(){
vec3 color = vec3( texture(renderedTexture, UV).r );
outColor = vec4(color, 1.0);
}

Answer 1

Nevermind, it does work! My problem was the depth-only FBO setup for the depth texture was never called.