Space Heater

spaceheater.cpp

#include <GL/glew.h>

#include <GLFW/glfw3.h>

#include <string>
#include <iostream>
#include <thread>
#include <random>
#include <algorithm>
#include <chrono>


void fpu_thread() {
    double x = 1;
    for (;;) {
        x = sin(cos(sin(cos(sin(cos(sin(cos(x))))))));
    }
}

void alu_thread() {
    std::mt19937_64 rand;
    for (;;) {
        rand();
    }
}

void gpu_thread() {
    glfwInit();
    glfwWindowHint(GLFW_VISIBLE, GL_FALSE);
    auto context = glfwCreateWindow(1024, 1024, "", nullptr, nullptr);
    glfwMakeContextCurrent(context);
    glewInit();
    glLoadIdentity();
    glOrtho(0, 1, 1, 0, -1, 1);
    GLuint vbo;
    glGenBuffers(1, &vbo);
    glBindBuffer(GL_ARRAY_BUFFER, vbo);
    float a[] = {
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1,
        0, 0, 1, 0, 1, 1, 0, 1
    };
    glBufferData(GL_ARRAY_BUFFER, sizeof(a), a, GL_STATIC_DRAW);
    glEnableClientState(GL_VERTEX_ARRAY);
    glVertexPointer(2, GL_FLOAT, 0, nullptr);
    for (;;) {
        for (int i = 0; i < 0x10; ++i) {
            glDrawArrays(GL_QUADS, 0, 64);
        }
        glfwSwapBuffers(context);
        glfwPollEvents();
    }
}

int main() {
    int number;
    std::cout << "Enter number of floating point threads: ";
    std::cin >> number;
    number = std::min(16, std::max(0, number));
    for (int i = 0; i < number; ++i) {
        std::thread(fpu_thread).detach();
    }
    std::cout << "Enter number of integer threads: ";
    std::cin >> number;
    number = std::min(16, std::max(0, number));
    for (int i = 0; i < number; ++i) {
        std::thread(alu_thread).detach();
    }
    std::cout << "Enter number of gpu threads: ";
    std::cin >> number;
    number = std::min(16, std::max(0, number));
    for (int i = 0; i < number; ++i) {
        std::thread(gpu_thread).detach();
    }
    for (;;) {
        std::this_thread::sleep_for(std::chrono::seconds(1));
    }
}