feat: square indicies

src/HelloTriangleApplication.cpp

@@ -43,10 +43,20 @@ struct Vertex {
     }
 };
 
+//const std::vector<Vertex> vertices = {
+//        {{0.0f, -0.5f}, {1.0f, 0.0f, 0.0f}},
+//        {{0.5f, 0.5f}, {0.0f, 1.0f, 0.0f}},
+//        {{-0.5f, 0.5f}, {0.0f, 0.0f, 1.0f}},
+//};
 const std::vector<Vertex> vertices = {
-        {{0.0f, -0.5f}, {1.0f, 0.0f, 0.0f}},
+        {{-0.5f, -0.5f}, {1.0f, 0.0f, 0.0f}},
-        {{0.5f, 0.5f}, {0.0f, 1.0f, 0.0f}},
+        {{0.5f, -0.5f},  {0.0f, 1.0f, 0.0f}},
-        {{-0.5f, 0.5f}, {0.0f, 0.0f, 1.0f}},
+        {{0.5f, 0.5f},   {0.0f, 0.0f, 1.0f}},
+        {{-0.5f, 0.5f},  {1.0f, 1.0f, 1.0f}},
+};
+
+const std::vector<uint16_t> indices = {
+        0, 1, 2, 2, 3, 0,
 };
 
 VkShaderModule HelloTriangleApplication::createShaderModule(const std::vector<char> &code) {
@@ -423,6 +433,27 @@ void HelloTriangleApplication::createVertexBuffer() {
     vkFreeMemory(myVkInstance->device, stagingBufferMemory, nullptr);
 }
 
+void HelloTriangleApplication::createIndexBuffer() {
+    VkDeviceSize bufferSize = sizeof(indices[0]) * indices.size();
+
+    VkBuffer stagingBuffer;
+    VkDeviceMemory stagingBufferMemory;
+    createBuffer(bufferSize, VK_BUFFER_USAGE_TRANSFER_SRC_BIT,
+                 VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT, stagingBuffer, stagingBufferMemory);
+
+    void* data;
+    vkMapMemory(myVkInstance->device, stagingBufferMemory, 0, bufferSize, 0, &data);
+    memcpy(data, indices.data(), (size_t)bufferSize);
+    vkUnmapMemory(myVkInstance->device, stagingBufferMemory);
+
+    createBuffer(bufferSize, VK_BUFFER_USAGE_TRANSFER_DST_BIT | VK_BUFFER_USAGE_INDEX_BUFFER_BIT,
+                 VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, indexBuffer, indexBufferMemory);
+    copyBuffer(stagingBuffer, indexBuffer, bufferSize);
+
+    vkDestroyBuffer(myVkInstance->device, stagingBuffer, nullptr);
+    vkFreeMemory(myVkInstance->device, stagingBufferMemory, nullptr);
+}
+
 void HelloTriangleApplication::copyBuffer(VkBuffer srcBuffer, VkBuffer dstBuffer, VkDeviceSize size) {
     VkCommandBufferAllocateInfo commandBufferAllocateInfo{
         .sType = VK_STRUCTURE_TYPE_COMMAND_BUFFER_ALLOCATE_INFO,
@@ -505,7 +536,8 @@ void HelloTriangleApplication::createCommandBuffers() {
         VkBuffer vertexBuffers[] = {vertexBuffer};
         VkDeviceSize offset[] = {0};
         vkCmdBindVertexBuffers(commandBuffers[i], 0, 1, vertexBuffers, offset);
-        vkCmdDraw(commandBuffers[i], static_cast<uint32_t>(vertices.size()), 1, 0, 0);
+        vkCmdBindIndexBuffer(commandBuffers[i], indexBuffer, 0, VK_INDEX_TYPE_UINT16);
+        vkCmdDrawIndexed(commandBuffers[i], static_cast<uint32_t>(indices.size()), 1, 0, 0, 0);
         vkCmdEndRenderPass(commandBuffers[i]);
         if (vkEndCommandBuffer(commandBuffers[i]) != VK_SUCCESS) {
             throw std::runtime_error{"Failed to record command buffer"};
@@ -543,6 +575,7 @@ void HelloTriangleApplication::initVulkan() {
     createFrameBuffers();
     createCommandPool();
     createVertexBuffer();
+    createIndexBuffer();
     createCommandBuffers();
     createSyncObjects();
 }
@@ -669,6 +702,9 @@ void HelloTriangleApplication::cleanup() {
     vkDestroyBuffer(myVkInstance->device, vertexBuffer, nullptr);
     vkFreeMemory(myVkInstance->device, vertexBufferMemory, nullptr);
 
+    vkDestroyBuffer(myVkInstance->device, indexBuffer, nullptr);
+    vkFreeMemory(myVkInstance->device, indexBufferMemory, nullptr);
+
     for (int i = 0; i < MAX_FRAMES_IN_FLIGHT; ++i) {
         vkDestroySemaphore(myVkInstance->device, renderFinishedSemaphores[i], nullptr);
         vkDestroySemaphore(myVkInstance->device, imageAvailableSemaphores[i], nullptr);

src/HelloTriangleApplication.h

@@ -32,6 +32,8 @@ private:
     std::vector<VkFramebuffer> swapChainFrameBuffers;
     VkBuffer vertexBuffer;
     VkDeviceMemory vertexBufferMemory;
+    VkBuffer indexBuffer;
+    VkDeviceMemory indexBufferMemory;
     VkCommandPool commandPool;
     std::vector<VkCommandBuffer> commandBuffers;
 
@@ -50,6 +52,7 @@ private:
     void createFrameBuffers();
     void createCommandPool();
     void createVertexBuffer();
+    void createIndexBuffer();
     void createCommandBuffers();
     void createSyncObjects();
     void initVulkan();