std::pair<int, std::string> find_optimal_alphabet(
std::vector<std::string> const& words, int const timeout)
{
std::mt19937 rndGenerator(static_cast<unsigned int>
(std::chrono::system_clock::now().time_since_epoch().count()));
std::uniform_int_distribution<int> distribution(0, 25);
auto bestScore = std::make_pair<int, std::string>(0, std::string(""));
auto alpha = base_alphabet();
int iteration = 0;
auto start_time = std::chrono::system_clock::now();
while (true) {
auto crt_time = std::chrono::system_clock::now();
if (std::chrono::duration_cast<std::chrono::seconds>(crt_time - start_time)
> std::chrono::seconds(timeout))
break;
auto score = alphabet_score(words, alpha);
if (score > bestScore.first) {
bestScore.first = score;
bestScore.second = alphabet_string(alpha);
std::cout << score << " \t" << alphabet_string(alpha) <<
" iteration= " << iteration << std::endl;
}
alter_alphabet(alpha, rndGenerator, distribution);
iteration++;
if ((iteration % 1000) == 0)
alter_alphabet(alpha, rndGenerator, distribution);
if ((iteration % 5000) == 0)
alter_alphabet(alpha, rndGenerator, distribution);
if ((iteration % 50000) == 0)
shuffle_alphabet(alpha);
}
return bestScore;
}
// Create all threads and initialize shader push constants
void prepareMultiThreadedRenderer()
{
// Since this demo updates the command buffers on each frame
// we don't use the per-framebuffer command buffers from the
// base class, and create a single primary command buffer instead
VkCommandBufferAllocateInfo cmdBufAllocateInfo =
vkTools::initializers::commandBufferAllocateInfo(
cmdPool,
VK_COMMAND_BUFFER_LEVEL_PRIMARY,
1);
VK_CHECK_RESULT(vkAllocateCommandBuffers(device, &cmdBufAllocateInfo, &primaryCommandBuffer));
// Create a secondary command buffer for rendering the star sphere
cmdBufAllocateInfo.level = VK_COMMAND_BUFFER_LEVEL_SECONDARY;
VK_CHECK_RESULT(vkAllocateCommandBuffers(device, &cmdBufAllocateInfo, &secondaryCommandBuffer));
threadData.resize(numThreads);
float maxX = std::floor(std::sqrt(numThreads * numObjectsPerThread));
uint32_t posX = 0;
uint32_t posZ = 0;
std::mt19937 rndGenerator((unsigned)time(NULL));
std::uniform_real_distribution<float> uniformDist(0.0f, 1.0f);
for (uint32_t i = 0; i < numThreads; i++)
{
ThreadData *thread = &threadData[i];
// Create one command pool for each thread
VkCommandPoolCreateInfo cmdPoolInfo = vkTools::initializers::commandPoolCreateInfo();
cmdPoolInfo.queueFamilyIndex = swapChain.queueNodeIndex;
cmdPoolInfo.flags = VK_COMMAND_POOL_CREATE_RESET_COMMAND_BUFFER_BIT;
VK_CHECK_RESULT(vkCreateCommandPool(device, &cmdPoolInfo, nullptr, &thread->commandPool));
// One secondary command buffer per object that is updated by this thread
thread->commandBuffer.resize(numObjectsPerThread);
// Generate secondary command buffers for each thread
VkCommandBufferAllocateInfo secondaryCmdBufAllocateInfo =
vkTools::initializers::commandBufferAllocateInfo(
thread->commandPool,
VK_COMMAND_BUFFER_LEVEL_SECONDARY,
thread->commandBuffer.size());
VK_CHECK_RESULT(vkAllocateCommandBuffers(device, &secondaryCmdBufAllocateInfo, thread->commandBuffer.data()));
thread->pushConstBlock.resize(numObjectsPerThread);
thread->objectData.resize(numObjectsPerThread);
for (uint32_t j = 0; j < numObjectsPerThread; j++)
{
float theta = 2.0f * float(M_PI) * uniformDist(rndGenerator);
float phi = acos(1.0f - 2.0f * uniformDist(rndGenerator));
thread->objectData[j].pos = glm::vec3(sin(phi) * cos(theta), 0.0f, cos(phi)) * 35.0f;
thread->objectData[j].rotation = glm::vec3(0.0f, rnd(360.0f), 0.0f);
thread->objectData[j].deltaT = rnd(1.0f);
thread->objectData[j].rotationDir = (rnd(100.0f) < 50.0f) ? 1.0f : -1.0f;
thread->objectData[j].rotationSpeed = (2.0f + rnd(4.0f)) * thread->objectData[j].rotationDir;
thread->objectData[j].scale = 0.75f + rnd(0.5f);
thread->pushConstBlock[j].color = glm::vec3(rnd(1.0f), rnd(1.0f), rnd(1.0f));
}
}
}