reduce lag by introducing BLPRenderer cache class for BLP thumbnail rendering

src/noggit/TextureManager.cpp

@@ -3,15 +3,9 @@
 #include <math/vector_2d.hpp>
 #include <noggit/TextureManager.h>
 #include <noggit/Log.h> // LogDebug
-#include <opengl/context.hpp>
-#include <opengl/scoped.hpp>
-#include <opengl/shader.hpp>
 
 #include <QtCore/QString>
-#include <QtGui/QOffscreenSurface>
-#include <QtGui/QOpenGLFramebufferObjectFormat>
 #include <QtGui/QPixmap>
-#include <QtOpenGL/QGLPixelBuffer>
 
 #include <algorithm>
 
@@ -260,43 +254,126 @@ void blp_texture::finishLoading()
 
 namespace noggit
 {
-  QPixmap* render_blp_to_pixmap ( std::string const& blp_filename
-                               , int width
-                               , int height
-                               )
-  {
-    static std::map<std::tuple<std::string, int, int>, QPixmap> cache{};
-    std::tuple<std::string, int, int> const curEntry{blp_filename, width, height};
-    auto it{cache.find(curEntry)};
 
-    if(it != cache.end())
+  BLPRenderer::BLPRenderer()
-      return &it->second;
+  {
+    _cache = {};
 
     opengl::context::save_current_context const context_save (::gl);
-    QOpenGLContext context;
+    _context.create();
-    context.create();
 
-    QOpenGLFramebufferObjectFormat fmt;
+    _fmt.setSamples(1);
-    fmt.setSamples(1);
+    _fmt.setInternalTextureFormat(GL_RGBA8);
-    fmt.setInternalTextureFormat(GL_RGBA8);
 
-    QOffscreenSurface surface;
+    _surface.create();
-    surface.create();
 
-    context.makeCurrent(&surface);
+    _context.makeCurrent(&_surface);
 
-    opengl::context::scoped_setter const context_set (::gl, &context);
+    opengl::context::scoped_setter const context_set (::gl, &_context);
 
     opengl::scoped::bool_setter<GL_CULL_FACE, GL_FALSE> cull;
     opengl::scoped::bool_setter<GL_DEPTH_TEST, GL_FALSE> depth;
 
-    opengl::scoped::deferred_upload_vertex_arrays<1> vao;
+    _vao.upload();
-    vao.upload();
+    _buffers.upload();
-    opengl::scoped::deferred_upload_buffers<3> buffers;
+
-    buffers.upload();
+    GLuint const& indices_vbo = _buffers[0];
-    GLuint const& indices_vbo = buffers[0];
+    GLuint const& vertices_vbo = _buffers[1];
-    GLuint const& vertices_vbo = buffers[1];
+    GLuint const& texcoords_vbo = _buffers[2];
-    GLuint const& texcoords_vbo = buffers[2];
+
+    std::vector<math::vector_2d> vertices =
+        {
+             {-1.0f, -1.0f}
+            ,{-1.0f, 1.0f}
+            ,{ 1.0f, 1.0f}
+            ,{ 1.0f, -1.0f}
+        };
+    std::vector<math::vector_2d> texcoords =
+        {
+             {0.f, 0.f}
+            ,{0.f, 1.0f}
+            ,{1.0f, 1.0f}
+            ,{1.0f, 0.f}
+        };
+    std::vector<std::uint16_t> indices = {0,1,2, 2,3,0};
+
+    gl.bufferData<GL_ARRAY_BUFFER, math::vector_2d>(vertices_vbo, vertices, GL_STATIC_DRAW);
+    gl.bufferData<GL_ARRAY_BUFFER, math::vector_2d>(texcoords_vbo, texcoords, GL_STATIC_DRAW);
+    gl.bufferData<GL_ELEMENT_ARRAY_BUFFER, std::uint16_t>(indices_vbo, indices, GL_STATIC_DRAW);
+
+
+    _program.reset(new opengl::program
+                      (
+                          {
+                              {
+                                  GL_VERTEX_SHADER, R"code(
+                                  #version 330 core
+
+                                  in vec4 position;
+                                  in vec2 tex_coord;
+                                  out vec2 f_tex_coord;
+
+                                  uniform float width;
+                                  uniform float height;
+
+                                  void main()
+                                  {
+                                    f_tex_coord = vec2(tex_coord.x * width, -tex_coord.y * height);
+                                    gl_Position = vec4(position.x * width / 2, position.y * height / 2, position.z, 1.0);
+                                  }
+                                  )code"
+                              },
+                              {
+                                  GL_FRAGMENT_SHADER, R"code(
+                                  #version 330 core
+
+                                  uniform sampler2D tex;
+
+                                  in vec2 f_tex_coord;
+
+                                  layout(location = 0) out vec4 out_color;
+
+                                  void main()
+                                  {
+                                    out_color = vec4(texture(tex, f_tex_coord/2.f + vec2(0.5)).rgb, 1.);
+                                  }
+                                  )code"
+                              }
+                          }
+                      ));
+    
+    opengl::scoped::use_program shader (*_program.get());
+    
+    opengl::scoped::vao_binder const _ (_vao[0]);
+
+    {
+      opengl::scoped::buffer_binder<GL_ARRAY_BUFFER> vertices_binder (vertices_vbo);
+      shader.attrib("position", 2, GL_FLOAT, GL_FALSE, 0, 0);
+    }
+    {
+      opengl::scoped::buffer_binder<GL_ARRAY_BUFFER> texcoords_binder (texcoords_vbo);
+      shader.attrib("tex_coord", 2, GL_FLOAT, GL_FALSE, 0, 0);
+    }
+
+
+  }
+
+  QPixmap* BLPRenderer::render_blp_to_pixmap ( std::string const& blp_filename
+                                               , int width
+                                               , int height
+                                               )
+  {
+    std::tuple<std::string, int, int> const curEntry{blp_filename, width, height};
+    auto it{_cache.find(curEntry)};
+
+    if(it != _cache.end())
+      return &it->second;
+
+    opengl::context::save_current_context const context_save (::gl);
+
+    _context.makeCurrent(&_surface);
+
+    opengl::context::scoped_setter const context_set (::gl, &_context);
 
     opengl::texture::set_active_texture(0);
     blp_texture texture(blp_filename);
@@ -307,90 +384,25 @@ namespace noggit
 
     float h = static_cast<float>(height);
     float w = static_cast<float>(width);
-    float half_h = h * 0.5f;
-    float half_w = w * 0.5f;
 
-    std::vector<math::vector_2d> vertices =
+    QOpenGLFramebufferObject pixel_buffer(width, height, _fmt);
-    {
-       {-half_w, -half_h}
-      ,{-half_w, half_h}
-      ,{ half_w, half_h}
-      ,{ half_w, -half_h}
-    };
-    std::vector<math::vector_2d> texcoords =
-    {
-       {0.f, 0.f}
-      ,{0.f, h}
-      ,{w, h}
-      ,{w, 0.f}
-    };
-    std::vector<std::uint16_t> indices = {0,1,2, 2,3,0};
-
-    gl.bufferData<GL_ARRAY_BUFFER, math::vector_2d>(vertices_vbo, vertices, GL_STATIC_DRAW);
-    gl.bufferData<GL_ARRAY_BUFFER, math::vector_2d>(texcoords_vbo, texcoords, GL_STATIC_DRAW);
-    gl.bufferData<GL_ELEMENT_ARRAY_BUFFER, std::uint16_t>(indices_vbo, indices, GL_STATIC_DRAW);
-
-    QOpenGLFramebufferObject pixel_buffer(width, height, fmt);
     pixel_buffer.bind();
 
     gl.viewport(0, 0, w, h);
     gl.clearColor(.0f, .0f, .0f, 1.f);
     gl.clear(GL_COLOR_BUFFER_BIT);
-
+    
-    opengl::program program
+    opengl::scoped::use_program shader (*_program.get());
-    (
-      {
-        {
-          GL_VERTEX_SHADER, R"code(
-#version 330 core
-
-in vec4 position;
-in vec2 tex_coord;
-out vec2 f_tex_coord;
-
-void main()
-{
-f_tex_coord = vec2(tex_coord.x, -tex_coord.y);
-gl_Position = position;
-}
-)code"
-        },
-        {
-          GL_FRAGMENT_SHADER,
-          R"code(
-#version 330 core
-
-uniform sampler2D tex;
-
-in vec2 f_tex_coord;
-
-layout(location = 0) out vec4 out_color;
-
-void main()
-{
-out_color = vec4(texture(tex, f_tex_coord/2.f + vec2(0.5)).rgb, 1.);
-}
-)code"
-        }
-      }
-    );
-
-    opengl::scoped::use_program shader (program);
 
     shader.uniform("tex", 0);
+    shader.uniform("width", w);
+    shader.uniform("height", h);
+
     texture.bind();
 
-    opengl::scoped::vao_binder const _ (vao[0]);
+    opengl::scoped::vao_binder const _ (_vao[0]);
-
+    
-    {
+    opengl::scoped::buffer_binder<GL_ELEMENT_ARRAY_BUFFER> indices_binder(_buffers[0]);
-      opengl::scoped::buffer_binder<GL_ARRAY_BUFFER> vertices_binder (vertices_vbo);
-      shader.attrib("position", 2, GL_FLOAT, GL_FALSE, 0, 0);
-    }
-    {
-      opengl::scoped::buffer_binder<GL_ARRAY_BUFFER> texcoords_binder (texcoords_vbo);
-      shader.attrib("tex_coord", 2, GL_FLOAT, GL_FALSE, 0, 0);
-    }
-    opengl::scoped::buffer_binder<GL_ELEMENT_ARRAY_BUFFER> indices_binder(indices_vbo);
 
     gl.drawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, nullptr);
 
@@ -404,7 +416,7 @@ out_color = vec4(texture(tex, f_tex_coord/2.f + vec2(0.5)).rgb, 1.);
         ("failed rendering " + blp_filename + " to pixmap");
     }
 
-    return &(cache[curEntry] = std::move(result));
+    return &(_cache[curEntry] = std::move(result));
   }
 }
 

src/noggit/TextureManager.h

@@ -5,6 +5,13 @@
 #include <noggit/AsyncObject.h>
 #include <noggit/multimap_with_normalized_key.hpp>
 #include <opengl/texture.hpp>
+#include <opengl/context.hpp>
+#include <opengl/scoped.hpp>
+#include <opengl/shader.hpp>
+
+#include <QtGui/QOffscreenSurface>
+#include <QtGui/QOpenGLFramebufferObjectFormat>
+#include <QtOpenGL/QGLPixelBuffer>
 
 #include <boost/optional.hpp>
 
@@ -12,6 +19,7 @@
 #include <string>
 #include <vector>
 
+
 struct BLPHeader;
 
 struct blp_texture : public opengl::texture, AsyncObject
@@ -81,8 +89,35 @@ private:
 
 namespace noggit
 {
-  QPixmap* render_blp_to_pixmap ( std::string const& blp_filename
+
-                               , int width = -1
+  class BLPRenderer
-                               , int height = -1
+  {
-                               );
+  private:
+    BLPRenderer();
+
+    BLPRenderer( const BLPRenderer&);
+    BLPRenderer& operator=( BLPRenderer& );
+
+    std::map<std::tuple<std::string, int, int>, QPixmap> _cache;
+
+    QOpenGLContext _context;
+    QOpenGLFramebufferObjectFormat _fmt;
+    QOffscreenSurface _surface;
+    std::unique_ptr<opengl::program> _program;
+
+    opengl::scoped::deferred_upload_vertex_arrays<1> _vao;
+    opengl::scoped::deferred_upload_buffers<3> _buffers;
+
+  public:
+    static BLPRenderer& getInstance()
+    {
+      static BLPRenderer  instance;
+      return instance;
+    }
+
+    QPixmap* render_blp_to_pixmap ( std::string const& blp_filename, int width = -1, int height = -1);
+
+  };
+
+
 }

src/noggit/ui/About.cpp

@@ -23,7 +23,7 @@ namespace noggit
       new QVBoxLayout (this);
 
       auto icon (new QLabel (this));
-      icon->setPixmap (*render_blp_to_pixmap ("interface/icons/inv_potion_83.blp"));
+      icon->setPixmap (*BLPRenderer::getInstance().render_blp_to_pixmap ("interface/icons/inv_potion_83.blp"));
       layout()->addWidget (icon);
       //! \todo was Skurri32
       layout()->addWidget (new QLabel ("Noggit Studio", this));

src/noggit/ui/CurrentTexture.cpp

@@ -56,7 +56,7 @@ namespace noggit
       _need_update = false;
 
       show();
-      setPixmap (*render_blp_to_pixmap (_filename, width(), height()));
+      setPixmap (*BLPRenderer::getInstance().render_blp_to_pixmap (_filename, width(), height()));
       setToolTip(QString::fromStdString(_filename));
     }
 

src/noggit/ui/HelperModels.cpp

@@ -27,7 +27,7 @@ namespace noggit
       layout->addLayout (bottom_layout);
 
       auto icon (new QLabel (this));
-      icon->setPixmap (*render_blp_to_pixmap ("interface/icons/inv_misc_enggizmos_swissarmy.blp"));
+      icon->setPixmap (*BLPRenderer::getInstance().render_blp_to_pixmap ("interface/icons/inv_misc_enggizmos_swissarmy.blp"));
       top_layout->addWidget (icon);
       top_layout->addWidget (new QLabel ("Select a model to add.\nYou should select a chunk first.", this));
 

src/noggit/ui/SettingsPanel.cpp

@@ -175,7 +175,7 @@ namespace noggit
       new QHBoxLayout (warning);
       auto icon (new QLabel (warning));
       icon->setPixmap
-        (*render_blp_to_pixmap ("interface/gossipframe/availablequesticon.blp"));
+        (*BLPRenderer::getInstance().render_blp_to_pixmap ("interface/gossipframe/availablequesticon.blp"));
       warning->layout()->addWidget (icon);
       warning->layout()->addWidget
         (new QLabel ("Changes may not take effect until next launch.", warning));

src/noggit/ui/TexturingGUI.cpp

@@ -47,7 +47,7 @@ namespace noggit
             //! \note The one time Qt is const correct and we don't want that.
             auto that (const_cast<model_item*> (this));
             that->_rendered = true;
-            that->_pixmap = *render_blp_to_pixmap (data (Qt::DisplayRole).toString().prepend ("tileset/").toStdString(), 256, 256);
+            that->_pixmap = *BLPRenderer::getInstance().render_blp_to_pixmap (data (Qt::DisplayRole).toString().prepend ("tileset/").toStdString(), 256, 256);
           }
           return QIcon(_pixmap);
         }

src/noggit/ui/texture_palette_small.cpp

@@ -147,7 +147,7 @@ namespace noggit
       _texture_paths.emplace(display_name.toStdString());
 
       QListWidgetItem* list_item = new QListWidgetItem(_texture_list);
-      list_item->setIcon(*render_blp_to_pixmap(filename, _texture_list->iconSize().width(), _texture_list->iconSize().height()));
+      list_item->setIcon(*BLPRenderer::getInstance().render_blp_to_pixmap(filename, _texture_list->iconSize().width(), _texture_list->iconSize().height()));
       list_item->setToolTip(display_name);
       list_item->setFlags(Qt::ItemIsEnabled | Qt::ItemIsSelectable | Qt::ItemIsDragEnabled);
 

src/opengl/shader.cpp

@@ -128,7 +128,7 @@ namespace opengl
     }
   }
 
-  //! \todo cache lookups?
+  //! \todo _cache lookups?
   GLuint program::uniform_location (std::string const& name) const
   {
     return gl.getUniformLocation (*_handle, name.c_str());