glfw/tests/tearing.c
Camilla Berglund d68acb78bf Removed registering glfwTerminate with atexit.
Functions registered with atexit are called from the thread calling exit.
glfwTerminate should only be called from the main thread.  Mistakes should be
explicit.
2012-10-22 03:20:16 +02:00

107 lines
3.0 KiB
C

//========================================================================
// Vsync enabling test
// Copyright (c) Camilla Berglund <elmindreda@elmindreda.org>
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would
// be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
// be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
// distribution.
//
//========================================================================
//
// This test renders a high contrast, horizontally moving bar, allowing for
// visual verification of whether the set swap interval is indeed obeyed
//
//========================================================================
#include <GL/glfw3.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
static int swap_interval;
static void set_swap_interval(GLFWwindow window, int interval)
{
char title[256];
swap_interval = interval;
glfwSwapInterval(swap_interval);
sprintf(title, "Tearing detector (interval %i)", swap_interval);
glfwSetWindowTitle(window, title);
}
static void window_size_callback(GLFWwindow window, int width, int height)
{
glViewport(0, 0, width, height);
}
static void key_callback(GLFWwindow window, int key, int action)
{
if (key == GLFW_KEY_SPACE && action == GLFW_PRESS)
set_swap_interval(window, 1 - swap_interval);
}
int main(void)
{
float position;
GLFWwindow window;
if (!glfwInit())
{
fprintf(stderr, "Failed to initialize GLFW: %s\n", glfwErrorString(glfwGetError()));
exit(EXIT_FAILURE);
}
window = glfwCreateWindow(0, 0, GLFW_WINDOWED, "", NULL);
if (!window)
{
fprintf(stderr, "Failed to open GLFW window: %s\n", glfwErrorString(glfwGetError()));
glfwTerminate();
exit(EXIT_FAILURE);
}
glfwMakeContextCurrent(window);
set_swap_interval(window, swap_interval);
glfwSetWindowSizeCallback(window_size_callback);
glfwSetKeyCallback(key_callback);
glMatrixMode(GL_PROJECTION);
glOrtho(-1.f, 1.f, -1.f, 1.f, 1.f, -1.f);
glMatrixMode(GL_MODELVIEW);
while (!glfwGetWindowParam(window, GLFW_CLOSE_REQUESTED))
{
glClear(GL_COLOR_BUFFER_BIT);
position = cosf(glfwGetTime() * 4.f) * 0.75f;
glRectf(position - 0.25f, -1.f, position + 0.25f, 1.f);
glfwSwapBuffers(window);
glfwPollEvents();
}
glfwTerminate();
exit(EXIT_SUCCESS);
}