Placefile image rendering

scwx-qt/source/scwx/qt/gl/draw/placefile_images.cpp

@@ -0,0 +1,438 @@
+#include <scwx/qt/gl/draw/placefile_images.hpp>
+#include <scwx/qt/util/maplibre.hpp>
+#include <scwx/qt/util/texture_atlas.hpp>
+#include <scwx/util/logger.hpp>
+
+#include <QUrl>
+#include <boost/unordered/unordered_flat_map.hpp>
+
+namespace scwx
+{
+namespace qt
+{
+namespace gl
+{
+namespace draw
+{
+
+static const std::string logPrefix_ = "scwx::qt::gl::draw::placefile_images";
+static const auto        logger_    = scwx::util::Logger::Create(logPrefix_);
+
+static constexpr std::size_t kNumRectangles        = 1;
+static constexpr std::size_t kNumTriangles         = kNumRectangles * 2;
+static constexpr std::size_t kVerticesPerTriangle  = 3;
+static constexpr std::size_t kVerticesPerRectangle = kVerticesPerTriangle * 2;
+static constexpr std::size_t kPointsPerVertex      = 8;
+static constexpr std::size_t kPointsPerTexCoord    = 2;
+static constexpr std::size_t kImageBufferLength =
+   kNumTriangles * kVerticesPerTriangle * kPointsPerVertex;
+static constexpr std::size_t kTextureBufferLength =
+   kNumTriangles * kVerticesPerTriangle * kPointsPerTexCoord;
+
+struct PlacefileImageInfo
+{
+   PlacefileImageInfo(const std::string& imageFile,
+                      const std::string& baseUrlString)
+   {
+      // Resolve using base URL
+      auto baseUrl = QUrl::fromUserInput(QString::fromStdString(baseUrlString));
+      auto relativeUrl = QUrl(QString::fromStdString(imageFile));
+      resolvedUrl_     = baseUrl.resolved(relativeUrl).toString().toStdString();
+   }
+
+   void UpdateTextureInfo();
+
+   std::string             resolvedUrl_;
+   util::TextureAttributes texture_ {};
+   float                   scaledWidth_ {};
+   float                   scaledHeight_ {};
+};
+
+class PlacefileImages::Impl
+{
+public:
+   explicit Impl(const std::shared_ptr<GlContext>& context) :
+       context_ {context},
+       shaderProgram_ {nullptr},
+       uMVPMatrixLocation_(GL_INVALID_INDEX),
+       uMapMatrixLocation_(GL_INVALID_INDEX),
+       uMapScreenCoordLocation_(GL_INVALID_INDEX),
+       uMapDistanceLocation_(GL_INVALID_INDEX),
+       vao_ {GL_INVALID_INDEX},
+       vbo_ {GL_INVALID_INDEX},
+       numVertices_ {0}
+   {
+   }
+
+   ~Impl() {}
+
+   void UpdateBuffers();
+   void UpdateTextureBuffer();
+   void Update(bool textureAtlasChanged);
+
+   std::shared_ptr<GlContext> context_;
+
+   std::string baseUrl_ {};
+
+   bool dirty_ {false};
+   bool thresholded_ {false};
+
+   std::mutex imageMutex_;
+
+   boost::unordered_flat_map<std::string, PlacefileImageInfo>
+      currentImageFiles_ {};
+   boost::unordered_flat_map<std::string, PlacefileImageInfo> newImageFiles_ {};
+
+   std::vector<std::shared_ptr<const gr::Placefile::ImageDrawItem>>
+      currentImageList_ {};
+   std::vector<std::shared_ptr<const gr::Placefile::ImageDrawItem>>
+      newImageList_ {};
+
+   std::vector<float> currentImageBuffer_ {};
+   std::vector<GLint> currentThresholdBuffer_ {};
+   std::vector<float> newImageBuffer_ {};
+   std::vector<GLint> newThresholdBuffer_ {};
+
+   std::vector<float> textureBuffer_ {};
+
+   std::shared_ptr<ShaderProgram> shaderProgram_;
+   GLint                          uMVPMatrixLocation_;
+   GLint                          uMapMatrixLocation_;
+   GLint                          uMapScreenCoordLocation_;
+   GLint                          uMapDistanceLocation_;
+
+   GLuint                vao_;
+   std::array<GLuint, 3> vbo_;
+
+   GLsizei numVertices_;
+};
+
+PlacefileImages::PlacefileImages(const std::shared_ptr<GlContext>& context) :
+    DrawItem(context->gl()), p(std::make_unique<Impl>(context))
+{
+}
+PlacefileImages::~PlacefileImages() = default;
+
+PlacefileImages::PlacefileImages(PlacefileImages&&) noexcept = default;
+PlacefileImages&
+PlacefileImages::operator=(PlacefileImages&&) noexcept = default;
+
+void PlacefileImages::set_thresholded(bool thresholded)
+{
+   p->thresholded_ = thresholded;
+}
+
+void PlacefileImages::Initialize()
+{
+   gl::OpenGLFunctions& gl = p->context_->gl();
+
+   p->shaderProgram_ = p->context_->GetShaderProgram(
+      {{GL_VERTEX_SHADER, ":/gl/geo_texture2d.vert"},
+       {GL_GEOMETRY_SHADER, ":/gl/threshold.geom"},
+       {GL_FRAGMENT_SHADER, ":/gl/texture2d.frag"}});
+
+   p->uMVPMatrixLocation_ = p->shaderProgram_->GetUniformLocation("uMVPMatrix");
+   p->uMapMatrixLocation_ = p->shaderProgram_->GetUniformLocation("uMapMatrix");
+   p->uMapScreenCoordLocation_ =
+      p->shaderProgram_->GetUniformLocation("uMapScreenCoord");
+   p->uMapDistanceLocation_ =
+      p->shaderProgram_->GetUniformLocation("uMapDistance");
+
+   gl.glGenVertexArrays(1, &p->vao_);
+   gl.glGenBuffers(static_cast<GLsizei>(p->vbo_.size()), p->vbo_.data());
+
+   gl.glBindVertexArray(p->vao_);
+   gl.glBindBuffer(GL_ARRAY_BUFFER, p->vbo_[0]);
+   gl.glBufferData(GL_ARRAY_BUFFER, 0u, nullptr, GL_DYNAMIC_DRAW);
+
+   // aLatLong
+   gl.glVertexAttribPointer(0,
+                            2,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerVertex * sizeof(float),
+                            static_cast<void*>(0));
+   gl.glEnableVertexAttribArray(0);
+
+   // aXYOffset
+   gl.glVertexAttribPointer(1,
+                            2,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerVertex * sizeof(float),
+                            reinterpret_cast<void*>(2 * sizeof(float)));
+   gl.glEnableVertexAttribArray(1);
+
+   // aModulate
+   gl.glVertexAttribPointer(3,
+                            4,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerVertex * sizeof(float),
+                            reinterpret_cast<void*>(4 * sizeof(float)));
+   gl.glEnableVertexAttribArray(3);
+
+   gl.glBindBuffer(GL_ARRAY_BUFFER, p->vbo_[1]);
+   gl.glBufferData(GL_ARRAY_BUFFER, 0u, nullptr, GL_DYNAMIC_DRAW);
+
+   // aTexCoord
+   gl.glVertexAttribPointer(2,
+                            2,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerTexCoord * sizeof(float),
+                            static_cast<void*>(0));
+   gl.glEnableVertexAttribArray(2);
+
+   gl.glBindBuffer(GL_ARRAY_BUFFER, p->vbo_[2]);
+   gl.glBufferData(GL_ARRAY_BUFFER, 0u, nullptr, GL_DYNAMIC_DRAW);
+
+   // aThreshold
+   gl.glVertexAttribIPointer(5, //
+                             1,
+                             GL_INT,
+                             0,
+                             static_cast<void*>(0));
+   gl.glEnableVertexAttribArray(5);
+
+   p->dirty_ = true;
+}
+
+void PlacefileImages::Render(
+   const QMapLibreGL::CustomLayerRenderParameters& params,
+   bool                                            textureAtlasChanged)
+{
+   std::unique_lock lock {p->imageMutex_};
+
+   if (!p->currentImageList_.empty())
+   {
+      gl::OpenGLFunctions& gl = p->context_->gl();
+
+      gl.glBindVertexArray(p->vao_);
+
+      p->Update(textureAtlasChanged);
+      p->shaderProgram_->Use();
+      UseRotationProjection(params, p->uMVPMatrixLocation_);
+      UseMapProjection(
+         params, p->uMapMatrixLocation_, p->uMapScreenCoordLocation_);
+
+      if (p->thresholded_)
+      {
+         // If thresholding is enabled, set the map distance
+         units::length::nautical_miles<float> mapDistance =
+            util::maplibre::GetMapDistance(params);
+         gl.glUniform1f(p->uMapDistanceLocation_, mapDistance.value());
+      }
+      else
+      {
+         // If thresholding is disabled, set the map distance to 0
+         gl.glUniform1f(p->uMapDistanceLocation_, 0.0f);
+      }
+
+      // Interpolate texture coordinates
+      gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+      gl.glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+
+      // Draw images
+      gl.glDrawArrays(GL_TRIANGLES, 0, p->numVertices_);
+   }
+}
+
+void PlacefileImages::Deinitialize()
+{
+   gl::OpenGLFunctions& gl = p->context_->gl();
+
+   gl.glDeleteVertexArrays(1, &p->vao_);
+   gl.glDeleteBuffers(static_cast<GLsizei>(p->vbo_.size()), p->vbo_.data());
+
+   std::unique_lock lock {p->imageMutex_};
+
+   p->currentImageList_.clear();
+   p->currentImageFiles_.clear();
+   p->currentImageBuffer_.clear();
+   p->currentThresholdBuffer_.clear();
+   p->textureBuffer_.clear();
+}
+
+void PlacefileImageInfo::UpdateTextureInfo()
+{
+   texture_ = util::TextureAtlas::Instance().GetTextureAttributes(resolvedUrl_);
+
+   scaledWidth_  = texture_.sRight_ - texture_.sLeft_;
+   scaledHeight_ = texture_.tBottom_ - texture_.tTop_;
+}
+
+void PlacefileImages::StartImages(const std::string& baseUrl)
+{
+   p->baseUrl_ = baseUrl;
+
+   // Clear the new buffer
+   p->newImageList_.clear();
+   p->newImageFiles_.clear();
+   p->newImageBuffer_.clear();
+   p->newThresholdBuffer_.clear();
+}
+
+void PlacefileImages::AddImage(
+   const std::shared_ptr<gr::Placefile::ImageDrawItem>& di)
+{
+   if (di != nullptr)
+   {
+      p->newImageList_.emplace_back(di);
+   }
+}
+
+void PlacefileImages::FinishImages()
+{
+   // Update buffers
+   p->UpdateBuffers();
+
+   std::unique_lock lock {p->imageMutex_};
+
+   // Swap buffers
+   p->currentImageList_.swap(p->newImageList_);
+   p->currentImageFiles_.swap(p->newImageFiles_);
+   p->currentImageBuffer_.swap(p->newImageBuffer_);
+   p->currentThresholdBuffer_.swap(p->newThresholdBuffer_);
+
+   // Clear the new buffers
+   p->newImageList_.clear();
+   p->newImageFiles_.clear();
+   p->newImageBuffer_.clear();
+   p->newThresholdBuffer_.clear();
+
+   // Mark the draw item dirty
+   p->dirty_ = true;
+}
+
+void PlacefileImages::Impl::UpdateBuffers()
+{
+   newImageBuffer_.clear();
+   newImageBuffer_.reserve(newImageList_.size() * kImageBufferLength);
+   newThresholdBuffer_.clear();
+   newThresholdBuffer_.reserve(newImageList_.size() * kVerticesPerRectangle);
+   newImageFiles_.clear();
+
+   // Fixed modulate color
+   static const float mc0 = 1.0f;
+   static const float mc1 = 1.0f;
+   static const float mc2 = 1.0f;
+   static const float mc3 = 1.0f;
+
+   for (auto& di : newImageList_)
+   {
+      // Populate image file map
+      newImageFiles_.emplace(
+         std::piecewise_construct,
+         std::tuple {di->imageFile_},
+         std::forward_as_tuple(PlacefileImageInfo {di->imageFile_, baseUrl_}));
+
+      // Threshold value
+      units::length::nautical_miles<double> threshold = di->threshold_;
+      GLint thresholdValue = static_cast<GLint>(std::round(threshold.value()));
+
+      // Limit processing to groups of 3 (triangles)
+      std::size_t numElements = di->elements_.size() - di->elements_.size() % 3;
+      for (std::size_t i = 0; i < numElements; ++i)
+      {
+         auto& element = di->elements_[i];
+
+         // Latitude and longitude coordinates in degrees
+         const float lat = static_cast<float>(element.latitude_);
+         const float lon = static_cast<float>(element.longitude_);
+
+         // Base X/Y offsets in pixels
+         const float x = static_cast<float>(element.x_);
+         const float y = static_cast<float>(element.y_);
+
+         newImageBuffer_.insert(newImageBuffer_.end(),
+                                {lat, lon, x, y, mc0, mc1, mc2, mc3});
+         newThresholdBuffer_.insert(newThresholdBuffer_.end(),
+                                    {thresholdValue});
+      }
+   }
+}
+
+void PlacefileImages::Impl::UpdateTextureBuffer()
+{
+   textureBuffer_.clear();
+   textureBuffer_.reserve(currentImageList_.size() * kTextureBufferLength);
+
+   for (auto& di : currentImageList_)
+   {
+      // Get placefile image info. The key should always be found in the map, as
+      // it is populated when the placefile is updated.
+      auto                      it    = currentImageFiles_.find(di->imageFile_);
+      const PlacefileImageInfo& image = (it == currentImageFiles_.cend()) ?
+                                           currentImageFiles_.cbegin()->second :
+                                           it->second;
+
+      // Limit processing to groups of 3 (triangles)
+      std::size_t numElements = di->elements_.size() - di->elements_.size() % 3;
+      for (std::size_t i = 0; i < numElements; ++i)
+      {
+         auto& element = di->elements_[i];
+
+         // Texture coordinates
+         const float s =
+            image.texture_.sLeft_ + (image.scaledWidth_ * element.tu_);
+         const float t =
+            image.texture_.tTop_ + (image.scaledHeight_ * element.tv_);
+
+         textureBuffer_.insert(textureBuffer_.end(), {s, t});
+      }
+   }
+}
+
+void PlacefileImages::Impl::Update(bool textureAtlasChanged)
+{
+   gl::OpenGLFunctions& gl = context_->gl();
+
+   // If the texture atlas has changed
+   if (dirty_ || textureAtlasChanged)
+   {
+      // Update texture coordinates
+      for (auto& imageFile : currentImageFiles_)
+      {
+         imageFile.second.UpdateTextureInfo();
+      }
+
+      // Update OpenGL texture buffer data
+      UpdateTextureBuffer();
+
+      // Buffer texture data
+      gl.glBindBuffer(GL_ARRAY_BUFFER, vbo_[1]);
+      gl.glBufferData(GL_ARRAY_BUFFER,
+                      sizeof(float) * textureBuffer_.size(),
+                      textureBuffer_.data(),
+                      GL_DYNAMIC_DRAW);
+   }
+
+   // If buffers need updating
+   if (dirty_)
+   {
+      // Buffer vertex data
+      gl.glBindBuffer(GL_ARRAY_BUFFER, vbo_[0]);
+      gl.glBufferData(GL_ARRAY_BUFFER,
+                      sizeof(float) * currentImageBuffer_.size(),
+                      currentImageBuffer_.data(),
+                      GL_DYNAMIC_DRAW);
+
+      // Buffer threshold data
+      gl.glBindBuffer(GL_ARRAY_BUFFER, vbo_[2]);
+      gl.glBufferData(GL_ARRAY_BUFFER,
+                      sizeof(GLint) * currentThresholdBuffer_.size(),
+                      currentThresholdBuffer_.data(),
+                      GL_DYNAMIC_DRAW);
+
+      numVertices_ = static_cast<GLsizei>(currentImageBuffer_.size() /
+                                          kVerticesPerRectangle);
+   }
+
+   dirty_ = false;
+}
+
+} // namespace draw
+} // namespace gl
+} // namespace qt
+} // namespace scwx