So I have started to try to learn OpenGL, and I decided to use GLFW to assist in window creation. The problem is, since GLFW3 is so new, there are no tutorials on it yet and how to use it with modern OpenGL (3.3, specifically). Using the GLFW3 tutorial found on the website, which uses older OpenGL rendering (glBegin(GL_TRIANGLES), glVertex3f()), and such, I can get a triangle to render to the screen. The problem is, using new OpenGL, I can't get the same triangle to render to the screen.
I am new to OpenGL, and GLFW3 is new to most people, so I may be completely missing something obvious, but here is my code:
static const GLuint g_vertex_buffer_data[] =
{
-1.0f, -1.0f, 0.0f,
1.0f, -1.0f, 0.0f,
0.0f, 1.0f, 0.0f
};
int main(void)
{
GLFWwindow* window;
if(!glfwInit())
{
fprintf(stderr, "Failed to initialize GLFW.");
return -1;
}
glfwWindowHint(GLFW_SAMPLES, 4);
glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
window = glfwCreateWindow(800, 600, "Test Window", NULL, NULL);
if(!window)
{
glfwTerminate();
fprintf(stderr, "Failed to create a GLFW window");
return -1;
}
glfwMakeContextCurrent(window);
glewExperimental = GL_TRUE;
GLenum err = glewInit();
if(err != GLEW_OK)
{
glfwTerminate();
fprintf(stderr, "Failed to initialize GLEW");
fprintf(stderr, (char*)glewGetErrorString(err));
return -1;
}
GLuint VertexArrayID;
glGenVertexArrays(1, &VertexArrayID);
glBindVertexArray(VertexArrayID);
GLuint programID = LoadShaders("SimpleVertexShader.glsl", "SimpleFragmentShader.glsl");
GLuint vertexBuffer;
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(g_vertex_buffer_data), g_vertex_buffer_data, GL_STATIC_DRAW);
while(!glfwWindowShouldClose(window))
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(programID);
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, (void*)0);
glDrawArrays(GL_TRIANGLES, 0, 3);
glDisableVertexAttribArray(0);
glfwSwapBuffers(window);
glfwPollEvents();
}
glDeleteBuffers(1, &vertexBuffer);
glDeleteProgram(programID);
glfwDestroyWindow(window);
glfwTerminate();
exit(EXIT_SUCCESS);
}
I know it is not my shaders, they are super simple and I've checked them against GLFW 2.7 so I know that they work. I'm assuming that I've missed something crucial to using the OpenGL context with GLFW3, so any help locating the problem would be greatly appreciated.
