Add Renderer::UpdateGeometry()

Also add its implementations in Vulkan and OpenGL renderers. Use it in
ImguiBackend instead of recreating geometry buffers every frame.

src/engine/asset/mesh.cc

@@ -139,28 +139,16 @@ bool Mesh::Load(const std::string& file_name) {
       }
     }
   }
+  // TODO: Load indices
   return true;
 }
 
 size_t Mesh::GetVertexSize() const {
-  unsigned int size = 0;
+  return eng::GetVertexSize(vertex_description_);
-  for (auto& attr : vertex_description_) {
-    size += std::get<2>(attr) * std::get<3>(attr);
-  }
-  return size;
 }
 
 size_t Mesh::GetIndexSize() const {
-  switch (index_description_) {
+  return eng::GetIndexSize(index_description_);
-    case kDataType_Byte:
-      return sizeof(char);
-    case kDataType_UShort:
-      return sizeof(unsigned short);
-    case kDataType_UInt:
-      return sizeof(unsigned int);
-    default:
-      return 0;
-  }
 }
 
 }  // namespace eng

src/engine/engine.cc

@@ -144,6 +144,105 @@ void Engine::Update(float delta_time) {
   if (stats_visible_)
     ShowStats();
 
+  ImGui::ShowDemoWindow();
+#if 0
+  // ImVec2 center = ImGui::GetMainViewport()->GetCenter();
+  // ImGui::SetNextWindowPos(ImVec2(0, 0), ImGuiCond_Always, ImVec2(0, 0));
+
+  static ImGuiWindowFlags window_flags = ImGuiWindowFlags_NoDecoration | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoSavedSettings;
+  const ImGuiViewport* viewport = ImGui::GetMainViewport();
+  ImGui::SetNextWindowPos(viewport->Pos);
+  ImGui::SetNextWindowSize(viewport->Size);
+  ImGui::Begin("Stats", nullptr, window_flags);
+
+  static ImGuiTableFlags flags = ImGuiTableFlags_ScrollY | ImGuiTableFlags_RowBg | ImGuiTableFlags_BordersOuter | ImGuiTableFlags_BordersV | ImGuiTableFlags_Resizable | ImGuiTableFlags_Reorderable | ImGuiTableFlags_Hideable;
+
+  // // PushStyleCompact();
+  // ImGuiStyle& style = ImGui::GetStyle();
+  // ImGui::PushStyleVar(ImGuiStyleVar_FramePadding, ImVec2(style.FramePadding.x, (float)(int)(style.FramePadding.y * 0.60f)));
+  // ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(style.ItemSpacing.x, (float)(int)(style.ItemSpacing.y * 0.60f)));
+
+  // ImGui::CheckboxFlags("ImGuiTableFlags_ScrollY", &flags, ImGuiTableFlags_ScrollY);
+
+  // // PopStyleCompact();
+  // ImGui::PopStyleVar(2);
+
+  // When using ScrollX or ScrollY we need to specify a size for our table container!
+  // Otherwise by default the table will fit all available space, like a BeginChild() call.
+  // ImVec2 outer_size = ImVec2(0.0f, ImGui::GetTextLineHeightWithSpacing() * 8);
+  if (ImGui::BeginTable("table_scrolly", 3, flags))
+  {
+      ImGui::TableSetupScrollFreeze(0, 1); // Make top row always visible
+      ImGui::TableSetupColumn("One", ImGuiTableColumnFlags_None);
+      ImGui::TableSetupColumn("Two", ImGuiTableColumnFlags_None);
+      ImGui::TableSetupColumn("Three", ImGuiTableColumnFlags_None);
+      ImGui::TableHeadersRow();
+
+      // Demonstrate using clipper for large vertical lists
+      ImGuiListClipper clipper;
+      clipper.Begin(1000);
+      while (clipper.Step())
+      {
+          for (int row = clipper.DisplayStart; row < clipper.DisplayEnd; row++)
+          {
+              ImGui::TableNextRow();
+              // ImGuiSelectableFlags selectable_flags = ImGuiSelectableFlags_SpanAllColumns | ImGuiSelectableFlags_AllowOverlap;
+              for (int column = 0; column < 3; column++)
+              {
+                  char buf[32];
+                  sprintf(buf, "Hello %d,%d", column, row);
+                  ImGui::TableSetColumnIndex(column);
+                  ImGui::Selectable(buf, false, ImGuiSelectableFlags_SpanAllColumns);
+                  // ImGui::Text("Hello %d,%d", column, row);
+              }
+
+              // static int row_bg_target = 1;
+              // static int row_bg_type = 1;
+              // if (ImGui::TableGetColumnFlags() & ImGuiTableColumnFlags_IsHovered) {
+              //     ImU32 row_bg_color = ImGui::GetColorU32(row_bg_type == 1 ? ImVec4(0.7f, 0.3f, 0.3f, 0.65f) : ImVec4(0.2f + row * 0.1f, 0.2f, 0.2f, 0.65f)); // Flat or Gradient?
+              //     ImGui::TableSetBgColor(ImGuiTableBgTarget_RowBg0 + row_bg_target, row_bg_color);
+              //     // ImGui::TableSetBgColor(ImGuiTableBgTarget_CellBg, IM_COL32(0, 100, 0, 255));
+              // }
+          }
+      }
+      ImGui::EndTable();
+  }
+  ImGui::End();
+
+#else
+
+{
+    bool show_app_fullscreen = false;
+    static bool use_work_area = true;
+    static ImGuiWindowFlags flags = ImGuiWindowFlags_NoDecoration | ImGuiWindowFlags_NoMove | ImGuiWindowFlags_NoSavedSettings;
+
+    // We demonstrate using the full viewport area or the work area (without menu-bars, task-bars etc.)
+    // Based on your use case you may want one or the other.
+    const ImGuiViewport* viewport = ImGui::GetMainViewport();
+    ImGui::SetNextWindowPos(use_work_area ? viewport->WorkPos : viewport->Pos);
+    ImGui::SetNextWindowSize(use_work_area ? viewport->WorkSize : viewport->Size);
+
+    if (ImGui::Begin("Example: Fullscreen window", &show_app_fullscreen, flags))
+    {
+        ImGui::Checkbox("Use work area instead of main area", &use_work_area);
+        ImGui::SameLine();
+        // HelpMarker("Main Area = entire viewport,\nWork Area = entire viewport minus sections used by the main menu bars, task bars etc.\n\nEnable the main-menu bar in Examples menu to see the difference.");
+
+        ImGui::CheckboxFlags("ImGuiWindowFlags_NoBackground", &flags, ImGuiWindowFlags_NoBackground);
+        ImGui::CheckboxFlags("ImGuiWindowFlags_NoDecoration", &flags, ImGuiWindowFlags_NoDecoration);
+        ImGui::Indent();
+        ImGui::CheckboxFlags("ImGuiWindowFlags_NoTitleBar", &flags, ImGuiWindowFlags_NoTitleBar);
+        ImGui::CheckboxFlags("ImGuiWindowFlags_NoCollapse", &flags, ImGuiWindowFlags_NoCollapse);
+        ImGui::CheckboxFlags("ImGuiWindowFlags_NoScrollbar", &flags, ImGuiWindowFlags_NoScrollbar);
+        ImGui::Unindent();
+
+        if (ImGui::Button("Close this window"))
+            show_app_fullscreen = false;
+    }
+    ImGui::End();
+}
+#endif
+
   imgui_backend_.Render();
 }
 

src/engine/imgui_backend.cc

@@ -68,6 +68,9 @@ void ImguiBackend::Initialize() {
 }
 
 void ImguiBackend::Shutdown() {
+  for (auto& id : geometries_)
+    renderer_->DestroyGeometry(id);
+  geometries_.clear();
   ImGui::DestroyContext();
   shader_.reset();
 }
@@ -75,6 +78,7 @@ void ImguiBackend::Shutdown() {
 void ImguiBackend::CreateRenderResources(Renderer* renderer) {
   renderer_ = renderer;
   shader_->SetRenderer(renderer);
+  geometries_.clear();
 
   auto source = std::make_unique<ShaderSource>();
   if (source->Load("engine/imgui.glsl")) {
@@ -115,10 +119,6 @@ std::unique_ptr<InputEvent> ImguiBackend::OnInputEvent(
 }
 
 void ImguiBackend::NewFrame(float delta_time) {
-  for (auto& id : geometries_)
-    renderer_->DestroyGeometry(id);
-  geometries_.clear();
-
   ImGuiIO& io = ImGui::GetIO();
   io.DisplaySize = ImVec2((float)renderer_->GetScreenWidth(),
                           (float)renderer_->GetScreenHeight());
@@ -129,7 +129,8 @@ void ImguiBackend::NewFrame(float delta_time) {
 void ImguiBackend::Render() {
   ImGui::Render();
   ImDrawData* draw_data = ImGui::GetDrawData();
-  geometries_.resize(draw_data->CmdListsCount);
+  if (geometries_.size() < draw_data->CmdListsCount)
+    geometries_.resize(draw_data->CmdListsCount, 0);
   for (int n = 0; n < draw_data->CmdListsCount; n++) {
     const ImDrawList* cmd_list = draw_data->CmdLists[n];
     auto mesh = std::make_unique<Mesh>();
@@ -137,7 +138,11 @@ void ImguiBackend::Render() {
                  cmd_list->VtxBuffer.Size, cmd_list->VtxBuffer.Data,
                  kDataType_UShort, cmd_list->IdxBuffer.Size,
                  cmd_list->IdxBuffer.Data);
-    geometries_[n] = renderer_->CreateGeometry(std::move(mesh));
+    if (geometries_[n] == 0)
+      geometries_[n] = renderer_->CreateGeometry(mesh->primitive(),
+                                                 mesh->vertex_description(),
+                                                 mesh->index_description());
+    renderer_->UpdateGeometry(geometries_[n], std::move(mesh));
   }
 }
 

src/engine/renderer/opengl/renderer_opengl.cc

@@ -72,11 +72,21 @@ void RendererOpenGL::ResetScissor() {
 }
 
 uint64_t RendererOpenGL::CreateGeometry(std::unique_ptr<Mesh> mesh) {
+  auto id = CreateGeometry(mesh->primitive(), mesh->vertex_description(),
+                           mesh->index_description());
+  if (id != kInvalidId)
+    UpdateGeometry(id, std::move(mesh));
+  return id;
+}
+
+uint64_t RendererOpenGL::CreateGeometry(Primitive primitive,
+                                        VertexDescription vertex_description,
+                                        DataType index_description) {
   // Verify that we have a valid layout and get the total byte size per vertex.
-  GLuint vertex_size = mesh->GetVertexSize();
+  GLuint vertex_size = GetVertexSize(vertex_description);
   if (!vertex_size) {
     LOG(0) << "Invalid vertex layout";
-    return 0;
+    return kInvalidId;
   }
 
   GLuint vertex_array_id = 0;
@@ -85,30 +95,25 @@ uint64_t RendererOpenGL::CreateGeometry(std::unique_ptr<Mesh> mesh) {
     glBindVertexArray(vertex_array_id);
   }
 
-  // Create the vertex buffer and upload the data.
+  // Create the vertex buffer.
   GLuint vertex_buffer_id = 0;
   glGenBuffers(1, &vertex_buffer_id);
   glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer_id);
-  glBufferData(GL_ARRAY_BUFFER, mesh->num_vertices() * vertex_size,
-               mesh->GetVertices(), GL_STATIC_DRAW);
 
   // Make sure the vertex format is understood and the attribute pointers are
   // set up.
   std::vector<GeometryOpenGL::Element> vertex_layout;
-  if (!SetupVertexLayout(mesh->vertex_description(), vertex_size,
+  if (!SetupVertexLayout(vertex_description, vertex_size, vertex_array_objects_,
-                         vertex_array_objects_, vertex_layout)) {
+                         vertex_layout)) {
     LOG(0) << "Invalid vertex layout";
-    return 0;
+    return kInvalidId;
   }
 
-  // Create the index buffer and upload the data.
+  // Create the index buffer.
   GLuint index_buffer_id = 0;
-  if (mesh->GetIndices()) {
+  if (index_description != kDataType_Invalid) {
     glGenBuffers(1, &index_buffer_id);
     glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_buffer_id);
-    glBufferData(GL_ELEMENT_ARRAY_BUFFER,
-                 mesh->num_indices() * mesh->GetIndexSize(), mesh->GetIndices(),
-                 GL_STATIC_DRAW);
   }
 
   if (vertex_array_id) {
@@ -121,10 +126,10 @@ uint64_t RendererOpenGL::CreateGeometry(std::unique_ptr<Mesh> mesh) {
   }
 
   uint64_t resource_id = ++last_resource_id_;
-  geometries_[resource_id] = {(GLsizei)mesh->num_vertices(),
+  geometries_[resource_id] = {0,
-                              (GLsizei)mesh->num_indices(),
+                              0,
-                              kGlPrimitive[mesh->primitive()],
+                              kGlPrimitive[primitive],
-                              kGlDataType[mesh->index_description()],
+                              kGlDataType[index_description],
                               vertex_layout,
                               vertex_size,
                               vertex_array_id,
@@ -133,6 +138,31 @@ uint64_t RendererOpenGL::CreateGeometry(std::unique_ptr<Mesh> mesh) {
   return resource_id;
 }
 
+void RendererOpenGL::UpdateGeometry(uint64_t resource_id,
+                                    std::unique_ptr<Mesh> mesh) {
+  auto it = geometries_.find(resource_id);
+  if (it == geometries_.end())
+    return;
+
+  // Go with GL_STATIC_DRAW for the first update.
+  GLenum usage = it->second.num_vertices > 0 ? GL_STREAM_DRAW : GL_STATIC_DRAW;
+
+  // Upload the vertex data.
+  glBindBuffer(GL_ARRAY_BUFFER, it->second.vertex_buffer_id);
+  glBufferData(GL_ARRAY_BUFFER, mesh->num_vertices() * it->second.vertex_size,
+               mesh->GetVertices(), usage);
+  it->second.num_vertices = (GLsizei)mesh->num_vertices();
+
+  // Upload the index data.
+  if (it->second.index_buffer_id) {
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, it->second.index_buffer_id);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER,
+                 mesh->num_indices() * mesh->GetIndexSize(), mesh->GetIndices(),
+                 usage);
+    it->second.num_indices = (GLsizei)mesh->num_indices();
+  }
+}
+
 void RendererOpenGL::DestroyGeometry(uint64_t resource_id) {
   auto it = geometries_.find(resource_id);
   if (it == geometries_.end())

src/engine/renderer/opengl/renderer_opengl.h

@@ -39,6 +39,10 @@ class RendererOpenGL final : public Renderer {
   void ResetScissor() final;
 
   uint64_t CreateGeometry(std::unique_ptr<Mesh> mesh) final;
+  uint64_t CreateGeometry(Primitive primitive,
+                          VertexDescription vertex_description,
+                          DataType index_description = kDataType_Invalid) final;
+  void UpdateGeometry(uint64_t resource_id, std::unique_ptr<Mesh> mesh) final;
   void DestroyGeometry(uint64_t resource_id) final;
   void Draw(uint64_t resource_id,
             uint64_t num_indices = 0,

src/engine/renderer/renderer.h

@@ -46,6 +46,12 @@ class Renderer {
   virtual void ResetScissor() = 0;
 
   virtual uint64_t CreateGeometry(std::unique_ptr<Mesh> mesh) = 0;
+  virtual uint64_t CreateGeometry(
+      Primitive primitive,
+      VertexDescription vertex_description,
+      DataType index_description = kDataType_Invalid) = 0;
+  virtual void UpdateGeometry(uint64_t resource_id,
+                              std::unique_ptr<Mesh> mesh) = 0;
   virtual void DestroyGeometry(uint64_t resource_id) = 0;
   virtual void Draw(uint64_t resource_id,
                     uint64_t num_indices = 0,

src/engine/renderer/renderer_types.cc

@@ -14,6 +14,27 @@ const char kLayoutDelimiter[] = ";/ \t";
 
 namespace eng {
 
+size_t GetVertexSize(const VertexDescription& vertex_description) {
+  size_t size = 0;
+  for (auto& attr : vertex_description) {
+    size += std::get<2>(attr) * std::get<3>(attr);
+  }
+  return size;
+}
+
+size_t GetIndexSize(DataType index_description)  {
+  switch (index_description) {
+    case kDataType_Byte:
+      return sizeof(char);
+    case kDataType_UShort:
+      return sizeof(unsigned short);
+    case kDataType_UInt:
+      return sizeof(unsigned int);
+    default:
+      return 0;
+  }
+}
+
 bool ParseVertexDescription(const std::string& vd_str, VertexDescription& out) {
   // Parse the description.
   char buffer[32];

src/engine/renderer/renderer_types.h

@@ -41,6 +41,9 @@ using DataTypeSize = size_t;
 using VertexDescription =
     std::vector<std::tuple<AttribType, DataType, ElementCount, DataTypeSize>>;
 
+size_t GetVertexSize(const VertexDescription& vertex_description);
+size_t GetIndexSize(DataType index_description);
+
 bool ParseVertexDescription(const std::string& vd_str, VertexDescription& out);
 
 }  // namespace eng

src/engine/renderer/vulkan/renderer_vulkan.cc

@@ -307,6 +307,8 @@ VertexInputDescription GetVertexInputDescription(
 
 VkIndexType GetIndexType(eng::DataType data_type) {
   switch (data_type) {
+    case eng::kDataType_Invalid:
+      return VK_INDEX_TYPE_NONE_KHR;
     case eng::kDataType_UInt:
       return VK_INDEX_TYPE_UINT32;
     case eng::kDataType_UShort:
@@ -315,7 +317,7 @@ VkIndexType GetIndexType(eng::DataType data_type) {
       break;
   }
   NOTREACHED() << "Invalid index type: " << data_type;
-  return VK_INDEX_TYPE_UINT16;
+  return VK_INDEX_TYPE_NONE_KHR;
 }
 
 VkFormat GetImageFormat(eng::Image::Format format) {
@@ -442,47 +444,71 @@ void RendererVulkan::ResetScissor() {
 }
 
 uint64_t RendererVulkan::CreateGeometry(std::unique_ptr<Mesh> mesh) {
-  auto& geometry = geometries_[++last_resource_id_] = {};
+  auto id = CreateGeometry(mesh->primitive(), mesh->vertex_description(),
+                           mesh->index_description());
+  if (id != kInvalidId)
+    UpdateGeometry(id, std::move(mesh));
+  return id;
+}
 
-  geometry.num_vertices = mesh->num_vertices();
+uint64_t RendererVulkan::CreateGeometry(Primitive primitive,
-  size_t vertex_data_size = mesh->GetVertexSize() * geometry.num_vertices;
+                                        VertexDescription vertex_description,
+                                        DataType index_description) {
+  auto& geometry = geometries_[++last_resource_id_] = {};
+  geometry.vertex_size = GetVertexSize(vertex_description);
+  geometry.index_type = GetIndexType(index_description);
+  geometry.index_type_size = GetIndexSize(index_description);
+  return last_resource_id_;
+}
+
+void RendererVulkan::UpdateGeometry(uint64_t resource_id,
+                                    std::unique_ptr<Mesh> mesh) {
+  auto it = geometries_.find(resource_id);
+  if (it == geometries_.end())
+    return;
+
+  it->second.num_vertices = mesh->num_vertices();
+  size_t vertex_data_size = it->second.vertex_size * it->second.num_vertices;
   size_t index_data_size = 0;
 
   if (mesh->GetIndices()) {
-    geometry.num_indices = mesh->num_indices();
+    DCHECK(it->second.index_type != VK_INDEX_TYPE_NONE_KHR);
-    geometry.index_type = GetIndexType(mesh->index_description());
+    it->second.num_indices = mesh->num_indices();
-    geometry.index_type_size = mesh->GetIndexSize();
+    index_data_size = it->second.index_type_size * it->second.num_indices;
-    index_data_size = geometry.index_type_size * geometry.num_indices;
   }
-  size_t data_size = vertex_data_size + index_data_size;
 
-  AllocateBuffer(geometry.buffer, data_size,
+  size_t data_size = vertex_data_size + index_data_size;
-                 VK_BUFFER_USAGE_TRANSFER_SRC_BIT |
+  if (it->second.buffer_size < data_size) {
-                     VK_BUFFER_USAGE_TRANSFER_DST_BIT |
+    DLOG(1) << __func__ << "Reallocate buffer " << data_size;
-                     VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+    if (it->second.buffer_size > 0)
-                 VMA_MEMORY_USAGE_GPU_ONLY);
+      FreeBuffer(std::move(it->second.buffer));
+    AllocateBuffer(it->second.buffer, data_size,
+                   VK_BUFFER_USAGE_TRANSFER_SRC_BIT |
+                       VK_BUFFER_USAGE_TRANSFER_DST_BIT |
+                       VK_BUFFER_USAGE_VERTEX_BUFFER_BIT,
+                   VMA_MEMORY_USAGE_GPU_ONLY);
+    it->second.buffer_size = data_size;
+  }
 
   task_runner_.PostTask(HERE, std::bind(&RendererVulkan::UpdateBuffer, this,
-                                        std::get<0>(geometry.buffer), 0,
+                                        std::get<0>(it->second.buffer), 0,
                                         mesh->GetVertices(), vertex_data_size));
-  if (geometry.num_indices > 0) {
+  if (it->second.num_indices > 0) {
-    geometry.index_data_offset = vertex_data_size;
+    it->second.index_data_offset = vertex_data_size;
     task_runner_.PostTask(HERE, std::bind(&RendererVulkan::UpdateBuffer, this,
-                                          std::get<0>(geometry.buffer),
+                                          std::get<0>(it->second.buffer),
-                                          geometry.index_data_offset,
+                                          it->second.index_data_offset,
                                           mesh->GetIndices(), index_data_size));
   }
   task_runner_.PostTask(HERE,
                         std::bind(&RendererVulkan::BufferMemoryBarrier, this,
-                                  std::get<0>(geometry.buffer), 0, data_size,
+                                  std::get<0>(it->second.buffer), 0, data_size,
                                   VK_PIPELINE_STAGE_TRANSFER_BIT,
                                   VK_PIPELINE_STAGE_VERTEX_INPUT_BIT,
                                   VK_ACCESS_TRANSFER_WRITE_BIT,
                                   VK_ACCESS_VERTEX_ATTRIBUTE_READ_BIT));
   task_runner_.Delete(HERE, std::move(mesh));
   semaphore_.release();
-
-  return last_resource_id_;
 }
 
 void RendererVulkan::DestroyGeometry(uint64_t resource_id) {

src/engine/renderer/vulkan/renderer_vulkan.h

@@ -40,6 +40,10 @@ class RendererVulkan final : public Renderer {
   void ResetScissor() final;
 
   uint64_t CreateGeometry(std::unique_ptr<Mesh> mesh) final;
+  uint64_t CreateGeometry(Primitive primitive,
+                          VertexDescription vertex_description,
+                          DataType index_description = kDataType_Invalid) final;
+  void UpdateGeometry(uint64_t resource_id, std::unique_ptr<Mesh> mesh) final;
   void DestroyGeometry(uint64_t resource_id) final;
   void Draw(uint64_t resource_id,
             uint64_t num_indices = 0,
@@ -107,11 +111,13 @@ class RendererVulkan final : public Renderer {
 
   struct GeometryVulkan {
     Buffer<VkBuffer> buffer;
+    size_t buffer_size = 0;
     uint32_t num_vertices = 0;
     uint32_t num_indices = 0;
+    size_t vertex_size = 0;
     uint64_t index_data_offset = 0;
     uint64_t index_type_size = 0;
-    VkIndexType index_type = VK_INDEX_TYPE_UINT16;
+    VkIndexType index_type = VK_INDEX_TYPE_NONE_KHR;
   };
 
   struct ShaderVulkan {