I’m using OpenGL to display a pattern on a 240 Hz screen with Nvidia GTX 1070 1582 MHz graphics card, and I’m encountering some problems with frame dropping/ skipping. To simplify the problem, I created a program that change the background color of the screen between black and white for every frame. The behavior that I observed is this:
- During the first 11 seconds, 2-4 small glitches (a frame dropped or a frame skipped) will occur
- At around 30 seconds, a “big glitch” occurs. This is either a white or black flash that span several frames.
- After that, the black-white-black transitions perfectly every frame (the longest test I’ve run is 5 mins).
I’m not sure why the errors occur in a systematic manner like that. The simple program ensured that graphics rendering time is very fast, and the gpu should be fast enough to copy pixels to the screen.
Any ideas on what might be causing this.?
Code of the simple program:
int main(void)
{
// Initialise GLFW
if (!glfwInit())
{
fprintf(stderr, "Failed to initialize GLFW
");
getchar();
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); // To make MacOS happy; should not be needed
glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);
int count;
GLFWmonitor* primaryMonitor = glfwGetPrimaryMonitor();
const GLFWvidmode* mode = glfwGetVideoMode(primaryMonitor);
// Open a window and create its OpenGL context
window = glfwCreateWindow(mode->width, mode->height, "Playground", primaryMonitor, NULL);
if (window == NULL) {
fprintf(stderr, "Failed to open GLFW window. If you have an Intel GPU, they are not 3.3 compatible. Try the 2.1 version of the tutorials.
");
getchar();
glfwTerminate();
return -1;
}
glfwMakeContextCurrent(window);
// Initialize GLEW
glewExperimental = true; // Needed for core profile
if (glewInit() != GLEW_OK) {
fprintf(stderr, "Failed to initialize GLEW
");
getchar();
glfwTerminate();
return -1;
}
// Ensure we can capture the escape key being pressed below
glfwSetInputMode(window, GLFW_STICKY_KEYS, GL_TRUE);
// Enable VSync
glfwSwapInterval(1);
float grayValueNormal1 = 0.0f;
do {
grayValueNormal1 = 1 - grayValueNormal1;
// Alternate the screen from black to white to black every frame
glClear(GL_COLOR_BUFFER_BIT);
glClearColor(grayValueNormal1, grayValueNormal1, grayValueNormal1, 0.0f);
glfwSwapBuffers(window);
glfwPollEvents();
} // Check if the ESC key was pressed or the window was closed
while (glfwGetKey(window, GLFW_KEY_ESCAPE) != GLFW_PRESS &&
glfwWindowShouldClose(window) == 0);
// Close OpenGL window and terminate GLFW
glfwTerminate();
return 0;
}