Untested geo line implementation without texture

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

@@ -0,0 +1,241 @@
+#include <scwx/qt/gl/draw/geo_line.hpp>
+#include <scwx/common/geographic.hpp>
+
+#include <optional>
+
+namespace scwx
+{
+namespace qt
+{
+namespace gl
+{
+namespace draw
+{
+
+static const std::string logPrefix_ = "scwx::qt::gl::draw::geo_line";
+
+static constexpr size_t kNumRectangles        = 1;
+static constexpr size_t kNumTriangles         = kNumRectangles * 2;
+static constexpr size_t kVerticesPerTriangle  = 3;
+static constexpr size_t kVerticesPerRectangle = kVerticesPerTriangle * 2;
+static constexpr size_t kPointsPerVertex      = 10;
+static constexpr size_t kBufferLength =
+   kNumTriangles * kVerticesPerTriangle * kPointsPerVertex;
+
+class GeoLine::Impl
+{
+public:
+   explicit Impl(OpenGLFunctions& gl) :
+       gl_ {gl},
+       dirty_ {false},
+       visible_ {true},
+       points_ {},
+       width_ {1.0f},
+       modulateColor_ {std::nullopt},
+       vao_ {GL_INVALID_INDEX},
+       vbo_ {GL_INVALID_INDEX}
+   {
+   }
+
+   ~Impl() {}
+
+   OpenGLFunctions& gl_;
+
+   bool dirty_;
+
+   bool                              visible_;
+   std::array<common::Coordinate, 2> points_;
+   float                             width_;
+
+   std::optional<boost::gil::rgba8_pixel_t> modulateColor_;
+
+   // TODO: Texture
+
+   GLuint vao_;
+   GLuint vbo_;
+
+   void Update();
+};
+
+// TODO: OpenGL context with shaders
+GeoLine::GeoLine(OpenGLFunctions& gl) :
+    DrawItem(), p(std::make_unique<Impl>(gl))
+{
+}
+GeoLine::~GeoLine() = default;
+
+GeoLine::GeoLine(GeoLine&&) noexcept            = default;
+GeoLine& GeoLine::operator=(GeoLine&&) noexcept = default;
+
+void GeoLine::Initialize()
+{
+   gl::OpenGLFunctions& gl = p->gl_;
+
+   gl.glGenVertexArrays(1, &p->vao_);
+   gl.glGenBuffers(1, &p->vbo_);
+
+   gl.glBindVertexArray(p->vao_);
+   gl.glBindBuffer(GL_ARRAY_BUFFER, p->vbo_);
+   gl.glBufferData(
+      GL_ARRAY_BUFFER, sizeof(float) * kBufferLength, 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);
+
+   // aTexCoord
+   gl.glVertexAttribPointer(2,
+                            2,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerVertex * sizeof(float),
+                            reinterpret_cast<void*>(4 * sizeof(float)));
+   gl.glEnableVertexAttribArray(2);
+
+   // aModulate
+   gl.glVertexAttribPointer(3,
+                            4,
+                            GL_FLOAT,
+                            GL_FALSE,
+                            kPointsPerVertex * sizeof(float),
+                            reinterpret_cast<void*>(6 * sizeof(float)));
+   gl.glEnableVertexAttribArray(3);
+
+   p->dirty_ = true;
+}
+
+void GeoLine::Render()
+{
+   if (p->visible_)
+   {
+      gl::OpenGLFunctions& gl = p->gl_;
+
+      gl.glBindVertexArray(p->vao_);
+      gl.glBindBuffer(GL_ARRAY_BUFFER, p->vbo_);
+
+      p->Update();
+
+      // Draw line
+      gl.glDrawArrays(GL_TRIANGLES, 0, 6);
+   }
+}
+
+void GeoLine::Deinitialize()
+{
+   gl::OpenGLFunctions& gl = p->gl_;
+
+   gl.glDeleteVertexArrays(1, &p->vao_);
+   gl.glDeleteBuffers(1, &p->vbo_);
+}
+
+void GeoLine::SetPoints(float latitude1,
+                        float longitude1,
+                        float latitude2,
+                        float longitude2)
+{
+   if (p->points_[0].latitude_ != latitude1 ||
+       p->points_[0].longitude_ != longitude1 ||
+       p->points_[1].latitude_ != latitude2 ||
+       p->points_[1].longitude_ != longitude2)
+   {
+      p->points_[0] = {latitude1, longitude1};
+      p->points_[1] = {latitude2, longitude2};
+      p->dirty_     = true;
+   }
+}
+
+void GeoLine::SetModulateColor(boost::gil::rgba8_pixel_t color)
+{
+   if (p->modulateColor_ != color)
+   {
+      p->modulateColor_ = color;
+      p->dirty_         = true;
+   }
+}
+
+void GeoLine::SetWidth(float width)
+{
+   if (p->width_ != width)
+   {
+      p->width_ = width;
+      p->dirty_ = true;
+   }
+}
+
+void GeoLine::SetVisible(bool visible)
+{
+   p->visible_ = visible;
+}
+
+void GeoLine::Impl::Update()
+{
+   if (dirty_)
+   {
+      gl::OpenGLFunctions& gl = gl_;
+
+      const float lx = points_[0].latitude_;
+      const float rx = points_[1].latitude_;
+      const float by = points_[0].longitude_;
+      const float ty = points_[1].longitude_;
+
+      const double i     = points_[1].longitude_ - points_[0].longitude_;
+      const double j     = points_[1].latitude_ - points_[0].latitude_;
+      const double angle = std::atan2(i, j) * 180.0 / M_PI;
+      const float  ox    = width_ * 0.5f * std::cosf(angle);
+      const float  oy    = width_ * 0.5f * std::sinf(angle);
+
+      float mc0 = 1.0f;
+      float mc1 = 1.0f;
+      float mc2 = 1.0f;
+      float mc3 = 1.0f;
+
+      if (modulateColor_.has_value())
+      {
+         boost::gil::rgba8_pixel_t& mc = modulateColor_.value();
+
+         mc0 = mc[0] / 255.0f;
+         mc1 = mc[1] / 255.0f;
+         mc2 = mc[2] / 255.0f;
+         mc3 = mc[3] / 255.0f;
+      }
+
+      const float buffer[kNumRectangles][kVerticesPerRectangle]
+                        [kPointsPerVertex] = //
+         {                                   //
+          // Line
+          {
+             {lx, by, -ox, -oy, 0.0f, 0.0f, mc0, mc1, mc2, mc3}, // BL
+             {lx, by, +ox, +oy, 0.0f, 1.0f, mc0, mc1, mc2, mc3}, // TL
+             {rx, ty, -ox, -oy, 1.0f, 0.0f, mc0, mc1, mc2, mc3}, // BR
+             {rx, ty, -ox, -oy, 1.0f, 0.0f, mc0, mc1, mc2, mc3}, // BR
+             {rx, ty, +ox, +oy, 1.0f, 1.0f, mc0, mc1, mc2, mc3}, // TR
+             {lx, by, +ox, +oy, 0.0f, 1.0f, mc0, mc1, mc2, mc3}  // TL
+          }};
+
+      gl.glBufferData(GL_ARRAY_BUFFER,
+                      sizeof(float) * kBufferLength,
+                      buffer,
+                      GL_DYNAMIC_DRAW);
+
+      dirty_ = false;
+   }
+}
+
+} // namespace draw
+} // namespace gl
+} // namespace qt
+} // namespace scwx

scwx-qt/source/scwx/qt/gl/draw/geo_line.hpp

@@ -0,0 +1,77 @@
+#pragma once
+
+#include <scwx/qt/gl/gl.hpp>
+#include <scwx/qt/gl/draw/draw_item.hpp>
+
+#include <boost/gil.hpp>
+
+namespace scwx
+{
+namespace qt
+{
+namespace gl
+{
+namespace draw
+{
+
+class GeoLine : public DrawItem
+{
+public:
+   explicit GeoLine(OpenGLFunctions& gl);
+   ~GeoLine();
+
+   GeoLine(const GeoLine&)            = delete;
+   GeoLine& operator=(const GeoLine&) = delete;
+
+   GeoLine(GeoLine&&) noexcept;
+   GeoLine& operator=(GeoLine&&) noexcept;
+
+   void Initialize() override;
+   void Render() override;
+   void Deinitialize() override;
+
+   /**
+    * Sets the geographic coordinate endpoints associated with the line.
+    *
+    * @param latitude1 Latitude of the first endpoint in degrees
+    * @param longitude1 Longitude of the first endpoint in degrees
+    * @param latitude2 Latitude of the second endpoint in degrees
+    * @param longitude2 Longitude of the second endpoint in degrees
+    */
+   void SetPoints(float latitude1,
+                  float longitude1,
+                  float latitude2,
+                  float longitude2);
+
+   /**
+    * Sets the modulate color of the line. If specified, the texture color will
+    * be multiplied by the modulate color to produce the result.
+    *
+    * @param color Modulate color (RGBA)
+    */
+   void SetModulateColor(boost::gil::rgba8_pixel_t color);
+
+   /**
+    * Sets the width of the line.
+    *
+    * @param width Width in pixels
+    */
+   void SetWidth(float width);
+
+   /**
+    * Sets the visibility of the line.
+    *
+    * @param visible
+    */
+   void SetVisible(bool visible);
+
+private:
+   class Impl;
+
+   std::unique_ptr<Impl> p;
+};
+
+} // namespace draw
+} // namespace gl
+} // namespace qt
+} // namespace scwx