Problem, getting black window with depth testing
I have a problem that my window becomes black when I enable GL_DEPTH_TEST. I suspect that my framebuffers aren't properly setup. I have included code that I believe to be minimal. As the code is right now an image appears. By removing the // before glEnable(GL_DEPTH_TEST); Screen goes black. I have tested with GL_ALWAYS and an image appears, but obviously no depth test.
I have looked up other questions about the same problem, but it was not the same cause or not enough information. I have been looking through many tutorials and I cannot find the solution to this problem.
To compile the code in gcc I use the following command.
gcc -o minimum main.c -lglut -lGL
#include
#include
#include
#include
extern void glGenFramebuffers (GLsizei n, GLuint *framebuffers);
extern void glBindFramebuffer (GLenum target, GLuint framebuffer);
extern void glFramebufferTexture2D (GLenum target, GLenum attachment, GLenum textar
get, GLuint texture , GLint level);
extern void glGenRenderbuffers (GLsizei n, GLuint *renderbuffers);
extern void glBindRenderbuffer (GLenum target, GLuint renderbuffer);
extern void glRenderbufferStorage (GLenum target, GLenum internalformat, GLsizei wi
dth, GLsizei height);
extern void glFramebufferRenderbuffer (GLenum target, GLenum attachment, GLenum ren
derbuffertarget, GLuint renderbuffer);
extern void glGenerateMipmap (GLenum target);
extern GLenum glCheckFramebufferStatus (GLenum target);
int main(int argc, char** argv)
{
GLuint t_color, t_depth, b_frame, b_render, t_sides[3];
unsigned char image1[16], image2[16], image3[16];
// Init images for textures on cube
image1[0] = 0; image1[1] = 0; image1[2] = 255; image1[3] = 0;
image1[4] = 255; image1[5] = 255; image1[6] = 0; image1[7] = 0;
image1[8] = 255; image1[9] = 255; image1[10] = 0; image1[11] = 0;
image1[12] = 0; image1[13] = 0; image1[14] = 255; image1[15] = 0;
image2[0] = 0; image2[1] = 0; image2[2] = 255; image2[3] = 0;
image2[4] = 255; image2[5] = 0; image2[6] = 0; image2[7] = 0;
image2[8] = 255; image2[9] = 0; image2[10] = 0; image2[11] = 0;
image2[12] = 0; image2[13] = 0; image2[14] = 255; image2[15] = 0;
image3[0] = 0; image3[1] = 0; image3[2] = 255; image3[3] = 0;
image3[4] = 0; image3[5] = 255; image3[6] = 0; image3[7] = 0;
image3[8] = 0; image3[9] = 255; image3[10] = 0; image3[11] = 0;
image3[12] = 0; image3[13] = 0; image3[14] = 255; image3[15] = 0;
// Init window
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA | GLUT_DEPTH);
glutInitWindowPosition(-1, -1);
glutInitWindowSize(640, 480);
glutCreateWindow("Test");
glClearColor(0.95f, 0.95f, 0.65f, 0.0f);
// glClearDepth(1.0f);
// glEnable(GL_DEPTH_TEST);
// glDepthFunc(GL_LESS);
// glDepthFunc(GL_ALWAYS);
// glEnable(GL_CULL_FACE);
// Generate color texture for framebuffer
glGenTextures(1, &t_color);
glBindTexture(GL_TEXTURE_2D, t_color);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 640, 480, 0, GL_RGBA, GL_UNSIGNED_B
YTE, NULL);
glBindTexture(GL_TEXTURE_2D, 0);
// Generate depth texture for framebuffer
glGenTextures(1, &t_depth);
glBindTexture(GL_TEXTURE_2D, t_depth);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT, 640, 480, 0, GL_DEPTH_CO
MPONENT, GL_UNSIGNED_BYTE, NULL);
glBindTexture(GL_TEXTURE_2D, 0);
// Generate framebuffer
glGenFramebuffers(1, &b_frame);
glBindFramebuffer(GL_FRAMEBUFFER, b_frame);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
t_color, 0);
glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_TEXTURE_2D,
t_depth, 0);
glGenRenderbuffers(1, &b_render);
glBindRenderbuffer(GL_RENDERBUFFER, b_render);
glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT24, 640, 480);
glFramebufferRenderbuffer (GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_
RENDERBUFFER, b_render);
glBindRenderbuffer(GL_RENDERBUFFER, 0);
GLenum status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
fprintf(stdout, "Status: %d\n", status);
fprintf(stdout, "Facit: %d\n", GL_FRAMEBUFFER_COMPLETE);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
// Generate textures for the sides of the cube
glGenTextures(3, t_sides);
glBindTexture(GL_TEXTURE_2D, t_sides[0]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 2, 2, 0, GL_BGRA, GL_UNSIGNED_BYTE,
image1);
glBindTexture(GL_TEXTURE_2D, 0);
glBindTexture(GL_TEXTURE_2D, t_sides[1]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 2, 2, 0, GL_BGRA, GL_UNSIGNED_BYTE,
image2);
glBindTexture(GL_TEXTURE_2D, 0);
glBindTexture(GL_TEXTURE_2D, t_sides[2]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 2, 2, 0, GL_BGRA, GL_UNSIGNED_BYTE,
image3);
glBindTexture(GL_TEXTURE_2D, 0);
glBindFramebuffer(GL_FRAMEBUFFER, b_frame);
glBindRenderbuffer(GL_RENDERBUFFER, b_render);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
glPushMatrix();
glRotatef(-5.0, 1, 0, 0);
glRotatef(5.0, 0, 1, 0);
// Bind the textures for the sides of the cube
glBindTexture(GL_TEXTURE_2D, t_sides[0]);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2f(0.0f,0.0f); glVertex3f(-0.5, -0.5, -0.25);
glTexCoord2f(1.0f,0.0f); glVertex3f( 0.5, -0.5, -0.25);
glTexCoord2f(1.0f,1.0f); glVertex3f( 0.5, 0.5, -0.25);
glTexCoord2f(0.0f,1.0f); glVertex3f(-0.5, 0.5, -0.25);
glEnd();
glBindTexture(GL_TEXTURE_2D, 0);
glBindTexture(GL_TEXTURE_2D, t_sides[1]);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2f(0.0f,0.0f); glVertex3f(-0.5, -0.5, -0.75);
glTexCoord2f(1.0f,0.0f); glVertex3f(-0.5, -0.5, -0.25);
glTexCoord2f(1.0f,1.0f); glVertex3f(-0.5, 0.5, -0.25);
glTexCoord2f(0.0f,1.0f); glVertex3f(-0.5, 0.5, -0.75);
glEnd();
glBindTexture(GL_TEXTURE_2D, 0);
glBindTexture(GL_TEXTURE_2D, t_sides[2]);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2f(0.0f,0.0f); glVertex3f(-0.5, 0.5, -0.25);
glTexCoord2f(1.0f,0.0f); glVertex3f( 0.5, 0.5, -0.25);
glTexCoord2f(1.0f,1.0f); glVertex3f( 0.5, 0.5, -0.75);
glTexCoord2f(0.0f,1.0f); glVertex3f(-0.5, 0.5, -0.75);
glEnd();
glBindTexture(GL_TEXTURE_2D, 0);
glPopMatrix();
glBindRenderbuffer(GL_RENDERBUFFER, 0);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
glBindTexture(GL_TEXTURE_2D, t_color);
glEnable(GL_TEXTURE_2D);
glBegin(GL_QUADS);
glTexCoord2f(0.0f,0.0f); glVertex3f(-1.0, -1.0, 0.0);
glTexCoord2f(1.0f,0.0f); glVertex3f( 1.0, -1.0, 0.0);
glTexCoord2f(1.0f,1.0f); glVertex3f( 1.0, 1.0, 0.0);
glTexCoord2f(0.0f,1.0f); glVertex3f(-1.0, 1.0, 0.0);
glEnd();
glBindTexture(GL_TEXTURE_2D, 0);
glFlush();
sleep(3);
}
Note: The reason I do not include GL/glext.h, is that it does nothing on my ubuntu system, I have to copy the function prototypes from the header file to get it to work.