using index buffer

main.cpp

@@ -45,11 +45,14 @@ const std::vector<const char *> gValidationLayers = {
 };
 
 const std::vector<Vertex> vertices = {
-    {{0.f, -0.5f}, {1.f, 0.f, 0.f}},
-    {{0.5f, 0.5f}, {0.f, 1.f, 0.f}},
-    {{-0.5f, 0.5f}, {0.f, 0.f, 1.f}},
+    {{-0.5f, -0.5f}, {1.f, 0.f, 0.f}},
+    {{0.5f, -0.5f}, {0.f, 1.f, 0.f}},
+    {{0.5f, 0.5f}, {0.f, 0.f, 1.f}},
+    {{-0.5f, 0.5f}, {1.f, 1.f, 1.f}},
 };
 
+const std::vector<uint16_t > indices = { 0, 1, 2, 2, 3, 0 };
+
 class Application {
 public:
   void run() {
@@ -107,6 +110,7 @@ private:
     createSynchronizationObjects();
 
     createVertexBuffer();
+    createIndexBuffer();
   }
 
   void mainLoop() {
@@ -782,7 +786,32 @@ private:
     }
 
     throw std::runtime_error("no suitable memory for vertex buffer found");
-    return  {};
+  }
+
+  void createIndexBuffer() {
+    VkDeviceSize size = sizeof(indices[0]) * indices.size();
+
+    VkBuffer stagingBuffer;
+    VkDeviceMemory stagingBufferMemory;
+
+    createBuffer(&stagingBuffer, &stagingBufferMemory,
+                 VK_MEMORY_PROPERTY_HOST_VISIBLE_BIT | VK_MEMORY_PROPERTY_HOST_COHERENT_BIT, size,
+                 VK_BUFFER_USAGE_TRANSFER_SRC_BIT);
+
+    {
+      void* memory;
+      vkMapMemory(mDevice, stagingBufferMemory, 0, size, 0, &memory);
+      memcpy(memory, indices.data(), size);
+      vkUnmapMemory(mDevice, stagingBufferMemory);
+    }
+
+    createBuffer(&mIndexBuffer, &mIndexBufferMemory,
+                 VK_MEMORY_PROPERTY_DEVICE_LOCAL_BIT, size,
+                 VK_BUFFER_USAGE_TRANSFER_DST_BIT | VK_BUFFER_USAGE_INDEX_BUFFER_BIT);
+
+    copyBuffer(stagingBuffer, mIndexBuffer, size);
+
+    destroyBuffer(stagingBuffer, stagingBufferMemory);
   }
 
   void createVertexBuffer() {
@@ -931,8 +960,9 @@ private:
     VkBuffer vertexBuffers[] = { mVertexBuffer };
     VkDeviceSize offsets[] = { 0 };
     vkCmdBindVertexBuffers(commandBuffer, 0, 1, vertexBuffers, offsets);
+    vkCmdBindIndexBuffer(commandBuffer, mIndexBuffer, 0, VK_INDEX_TYPE_UINT16);
 
-    vkCmdDraw(commandBuffer, vertices.size(), 1, 0, 0);
+    vkCmdDrawIndexed(commandBuffer, indices.size(), 1, 0, 0, 0);
 
     vkCmdEndRenderPass(commandBuffer);
 
@@ -1014,10 +1044,6 @@ private:
     */
   }
 
-  void createBuffer() {
-
-  }
-
   static VkVertexInputBindingDescription getShaderVertexInputDescription() {
     return {
         .binding = 0,
@@ -1054,6 +1080,7 @@ private:
 
   void cleanup() {
     destroyBuffer(mVertexBuffer, mVertexBufferMemory);
+    destroyBuffer(mIndexBuffer, mIndexBufferMemory);
 
     destroySynchronizationObjects();
 
@@ -1115,6 +1142,8 @@ private:
 
   VkBuffer mVertexBuffer = VK_NULL_HANDLE;
   VkDeviceMemory mVertexBufferMemory = VK_NULL_HANDLE;
+  VkBuffer mIndexBuffer = VK_NULL_HANDLE;
+  VkDeviceMemory mIndexBufferMemory = VK_NULL_HANDLE;
 };
 
 int main() {