From d84a618d3d724062073fb499dc183e71abccafd9 Mon Sep 17 00:00:00 2001
From: Dan Paulat <dpaulat@gmail.com>
Date: Sun, 2 Oct 2022 23:44:09 -0500
Subject: [PATCH] Add GlContext base class for MapContext

---
 scwx-qt/scwx-qt.cmake                      |  4 +-
 scwx-qt/source/scwx/qt/gl/gl_context.cpp   | 64 ++++++++++++++++++++++
 scwx-qt/source/scwx/qt/gl/gl_context.hpp   | 39 +++++++++++++
 scwx-qt/source/scwx/qt/gl/text_shader.cpp  |  8 +--
 scwx-qt/source/scwx/qt/gl/text_shader.hpp  |  4 +-
 scwx-qt/source/scwx/qt/map/map_context.cpp | 43 +--------------
 scwx-qt/source/scwx/qt/map/map_context.hpp | 10 +---
 7 files changed, 115 insertions(+), 57 deletions(-)
 create mode 100644 scwx-qt/source/scwx/qt/gl/gl_context.cpp
 create mode 100644 scwx-qt/source/scwx/qt/gl/gl_context.hpp

diff --git a/scwx-qt/scwx-qt.cmake b/scwx-qt/scwx-qt.cmake
index d3c2b421..1c4a0366 100644
--- a/scwx-qt/scwx-qt.cmake
+++ b/scwx-qt/scwx-qt.cmake
@@ -41,9 +41,11 @@ set(UI_MAIN  source/scwx/qt/main/main_window.ui)
 set(HDR_CONFIG source/scwx/qt/config/radar_site.hpp)
 set(SRC_CONFIG source/scwx/qt/config/radar_site.cpp)
 set(HDR_GL source/scwx/qt/gl/gl.hpp
+           source/scwx/qt/gl/gl_context.hpp
            source/scwx/qt/gl/shader_program.hpp
            source/scwx/qt/gl/text_shader.hpp)
-set(SRC_GL source/scwx/qt/gl/shader_program.cpp
+set(SRC_GL source/scwx/qt/gl/gl_context.cpp
+           source/scwx/qt/gl/shader_program.cpp
            source/scwx/qt/gl/text_shader.cpp)
 set(HDR_GL_DRAW source/scwx/qt/gl/draw/draw_item.hpp
                 source/scwx/qt/gl/draw/geo_line.hpp
diff --git a/scwx-qt/source/scwx/qt/gl/gl_context.cpp b/scwx-qt/source/scwx/qt/gl/gl_context.cpp
new file mode 100644
index 00000000..3db875a8
--- /dev/null
+++ b/scwx-qt/source/scwx/qt/gl/gl_context.cpp
@@ -0,0 +1,64 @@
+#include <scwx/qt/gl/gl_context.hpp>
+#include <scwx/util/hash.hpp>
+
+namespace scwx
+{
+namespace qt
+{
+namespace gl
+{
+
+class GlContext::Impl
+{
+public:
+   explicit Impl() : gl_ {}, shaderProgramMap_ {}, shaderProgramMutex_ {} {}
+   ~Impl() {}
+
+   gl::OpenGLFunctions gl_;
+
+   std::unordered_map<std::pair<std::string, std::string>,
+                      std::shared_ptr<gl::ShaderProgram>,
+                      util::hash<std::pair<std::string, std::string>>>
+              shaderProgramMap_;
+   std::mutex shaderProgramMutex_;
+};
+
+GlContext::GlContext() : p(std::make_unique<Impl>()) {}
+GlContext::~GlContext() = default;
+
+GlContext::GlContext(GlContext&&) noexcept            = default;
+GlContext& GlContext::operator=(GlContext&&) noexcept = default;
+
+gl::OpenGLFunctions& GlContext::gl()
+{
+   return p->gl_;
+}
+
+std::shared_ptr<gl::ShaderProgram>
+GlContext::GetShaderProgram(const std::string& vertexPath,
+                            const std::string& fragmentPath)
+{
+   const std::pair<std::string, std::string> key {vertexPath, fragmentPath};
+   std::shared_ptr<gl::ShaderProgram>        shaderProgram;
+
+   std::unique_lock lock(p->shaderProgramMutex_);
+
+   auto it = p->shaderProgramMap_.find(key);
+
+   if (it == p->shaderProgramMap_.end())
+   {
+      shaderProgram = std::make_shared<gl::ShaderProgram>(p->gl_);
+      shaderProgram->Load(vertexPath, fragmentPath);
+      p->shaderProgramMap_[key] = shaderProgram;
+   }
+   else
+   {
+      shaderProgram = it->second;
+   }
+
+   return shaderProgram;
+}
+
+} // namespace gl
+} // namespace qt
+} // namespace scwx
diff --git a/scwx-qt/source/scwx/qt/gl/gl_context.hpp b/scwx-qt/source/scwx/qt/gl/gl_context.hpp
new file mode 100644
index 00000000..cf81262f
--- /dev/null
+++ b/scwx-qt/source/scwx/qt/gl/gl_context.hpp
@@ -0,0 +1,39 @@
+#pragma once
+
+#include <scwx/qt/gl/gl.hpp>
+#include <scwx/qt/gl/shader_program.hpp>
+
+namespace scwx
+{
+namespace qt
+{
+namespace gl
+{
+
+class GlContext
+{
+public:
+   explicit GlContext();
+   virtual ~GlContext();
+
+   GlContext(const GlContext&)            = delete;
+   GlContext& operator=(const GlContext&) = delete;
+
+   GlContext(GlContext&&) noexcept;
+   GlContext& operator=(GlContext&&) noexcept;
+
+   gl::OpenGLFunctions& gl();
+
+   std::shared_ptr<gl::ShaderProgram>
+   GetShaderProgram(const std::string& vertexPath,
+                    const std::string& fragmentPath);
+
+private:
+   class Impl;
+
+   std::unique_ptr<Impl> p;
+};
+
+} // namespace gl
+} // namespace qt
+} // namespace scwx
diff --git a/scwx-qt/source/scwx/qt/gl/text_shader.cpp b/scwx-qt/source/scwx/qt/gl/text_shader.cpp
index 20f3a60a..ec8cdcf1 100644
--- a/scwx-qt/source/scwx/qt/gl/text_shader.cpp
+++ b/scwx-qt/source/scwx/qt/gl/text_shader.cpp
@@ -19,7 +19,7 @@ static const auto        logger_    = scwx::util::Logger::Create(logPrefix_);
 class TextShaderImpl
 {
 public:
-   explicit TextShaderImpl(std::shared_ptr<map::MapContext> context) :
+   explicit TextShaderImpl(std::shared_ptr<GlContext> context) :
        context_ {context},
        shaderProgram_ {nullptr},
        projectionLocation_(GL_INVALID_INDEX)
@@ -28,13 +28,13 @@ public:
 
    ~TextShaderImpl() {}
 
-   std::shared_ptr<map::MapContext> context_;
-   std::shared_ptr<ShaderProgram>   shaderProgram_;
+   std::shared_ptr<GlContext>     context_;
+   std::shared_ptr<ShaderProgram> shaderProgram_;
 
    GLint projectionLocation_;
 };
 
-TextShader::TextShader(std::shared_ptr<map::MapContext> context) :
+TextShader::TextShader(std::shared_ptr<GlContext> context) :
     p(std::make_unique<TextShaderImpl>(context))
 {
 }
diff --git a/scwx-qt/source/scwx/qt/gl/text_shader.hpp b/scwx-qt/source/scwx/qt/gl/text_shader.hpp
index 83553a08..ed81907a 100644
--- a/scwx-qt/source/scwx/qt/gl/text_shader.hpp
+++ b/scwx-qt/source/scwx/qt/gl/text_shader.hpp
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <scwx/qt/map/map_context.hpp>
+#include <scwx/qt/gl/gl_context.hpp>
 #include <scwx/qt/util/font.hpp>
 
 #include <memory>
@@ -27,7 +27,7 @@ class TextShaderImpl;
 class TextShader
 {
 public:
-   explicit TextShader(std::shared_ptr<map::MapContext> context);
+   explicit TextShader(std::shared_ptr<GlContext> context);
    ~TextShader();
 
    TextShader(const TextShader&)            = delete;
diff --git a/scwx-qt/source/scwx/qt/map/map_context.cpp b/scwx-qt/source/scwx/qt/map/map_context.cpp
index 1e19d9e6..68b94e8e 100644
--- a/scwx-qt/source/scwx/qt/map/map_context.cpp
+++ b/scwx-qt/source/scwx/qt/map/map_context.cpp
@@ -1,5 +1,4 @@
 #include <scwx/qt/map/map_context.hpp>
-#include <scwx/util/hash.hpp>
 
 namespace scwx
 {
@@ -12,31 +11,21 @@ class MapContext::Impl
 {
 public:
    explicit Impl(std::shared_ptr<view::RadarProductView> radarProductView) :
-       gl_ {},
        settings_ {},
        radarProductView_ {radarProductView},
        radarProductGroup_ {common::RadarProductGroup::Unknown},
        radarProduct_ {"???"},
-       radarProductCode_ {0},
-       shaderProgramMap_ {},
-       shaderProgramMutex_ {}
+       radarProductCode_ {0}
    {
    }
 
    ~Impl() {}
 
-   gl::OpenGLFunctions                     gl_;
    MapSettings                             settings_;
    std::shared_ptr<view::RadarProductView> radarProductView_;
    common::RadarProductGroup               radarProductGroup_;
    std::string                             radarProduct_;
    int16_t                                 radarProductCode_;
-
-   std::unordered_map<std::pair<std::string, std::string>,
-                      std::shared_ptr<gl::ShaderProgram>,
-                      util::hash<std::pair<std::string, std::string>>>
-              shaderProgramMap_;
-   std::mutex shaderProgramMutex_;
 };
 
 MapContext::MapContext(
@@ -49,11 +38,6 @@ MapContext::~MapContext() = default;
 MapContext::MapContext(MapContext&&) noexcept            = default;
 MapContext& MapContext::operator=(MapContext&&) noexcept = default;
 
-gl::OpenGLFunctions& MapContext::gl()
-{
-   return p->gl_;
-}
-
 MapSettings& MapContext::settings()
 {
    return p->settings_;
@@ -101,31 +85,6 @@ void MapContext::set_radar_product_code(int16_t radarProductCode)
    p->radarProductCode_ = radarProductCode;
 }
 
-std::shared_ptr<gl::ShaderProgram>
-MapContext::GetShaderProgram(const std::string& vertexPath,
-                             const std::string& fragmentPath)
-{
-   const std::pair<std::string, std::string> key {vertexPath, fragmentPath};
-   std::shared_ptr<gl::ShaderProgram>        shaderProgram;
-
-   std::unique_lock lock(p->shaderProgramMutex_);
-
-   auto it = p->shaderProgramMap_.find(key);
-
-   if (it == p->shaderProgramMap_.end())
-   {
-      shaderProgram = std::make_shared<gl::ShaderProgram>(p->gl_);
-      shaderProgram->Load(vertexPath, fragmentPath);
-      p->shaderProgramMap_[key] = shaderProgram;
-   }
-   else
-   {
-      shaderProgram = it->second;
-   }
-
-   return shaderProgram;
-}
-
 } // namespace map
 } // namespace qt
 } // namespace scwx
diff --git a/scwx-qt/source/scwx/qt/map/map_context.hpp b/scwx-qt/source/scwx/qt/map/map_context.hpp
index 95703f4a..47f3cc11 100644
--- a/scwx-qt/source/scwx/qt/map/map_context.hpp
+++ b/scwx-qt/source/scwx/qt/map/map_context.hpp
@@ -1,7 +1,6 @@
 #pragma once
 
-#include <scwx/qt/gl/gl.hpp>
-#include <scwx/qt/gl/shader_program.hpp>
+#include <scwx/qt/gl/gl_context.hpp>
 #include <scwx/qt/map/map_settings.hpp>
 #include <scwx/qt/view/radar_product_view.hpp>
 
@@ -12,7 +11,7 @@ namespace qt
 namespace map
 {
 
-class MapContext
+class MapContext : public gl::GlContext
 {
 public:
    explicit MapContext(
@@ -25,7 +24,6 @@ public:
    MapContext(MapContext&&) noexcept;
    MapContext& operator=(MapContext&&) noexcept;
 
-   gl::OpenGLFunctions&                    gl();
    MapSettings&                            settings();
    std::shared_ptr<view::RadarProductView> radar_product_view() const;
    common::RadarProductGroup               radar_product_group() const;
@@ -38,10 +36,6 @@ public:
    void set_radar_product(const std::string& radarProduct);
    void set_radar_product_code(int16_t radarProductCode);
 
-   std::shared_ptr<gl::ShaderProgram>
-   GetShaderProgram(const std::string& vertexPath,
-                    const std::string& fragmentPath);
-
 private:
    class Impl;