Add ResourceManager for assets outside of QRC

+ Use qt6_add_big_resources to improve build time
+ RM::getPath(sting) to build absolute path to assets
+ Allows easy access to models or other large assets not loaded into QRC

CMakeLists.txt

@@ -20,12 +20,16 @@ set(CMAKE_CXX_STANDARD 11)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 # For CLion builds, point CMAKE_PREFIX_PATH to Qt6 install directory
-list(APPEND CMAKE_PREFIX_PATH $ENV{HOME}/Code/Clones/Qt6.2/6.2.3/gcc_64/)
+list(APPEND CMAKE_PREFIX_PATH $ENV{HOME}/Code/Clones/Qt/6.3.1/gcc_64/)
-find_package(Qt6 COMPONENTS OpenGLWidgets REQUIRED)
+find_package(Qt6 COMPONENTS OpenGLWidgets)
+if (NOT Qt6_FOUND)
+  message(SEND_ERROR "Unable to find Qt6 at CMAKE_PREFIX_PATH: ${CMAKE_PREFIX_PATH}")
+  message(FATAL_ERROR "Specify path to Qt6 with `cmake -DCMAKE_PREFIX_PATH=/path/to/Qt/6.x.x/gcc_64 -S /path/to/qtk -B /path/to/qtk/build && cmake --build /path/to/qtk/build -j $(nprocs)`")
+endif()
 
 # Add our Qt resources.qrc file to our application
 set(SOURCES app/main.cpp)
-qt6_add_resources(SOURCES resources.qrc)
+qt6_add_big_resources(SOURCES resources.qrc)
 
 add_executable(
     qtk             # Executable name
@@ -59,6 +63,7 @@ add_library(main-widget SHARED
     src/transform3D.cpp src/transform3D.h
     src/model.cpp src/model.h
     src/scene.cpp src/scene.h
+    src/resourcemanager.cpp src/resourcemanager.h
 )
 
 target_include_directories(main-widget PUBLIC src/)

README.md

@@ -23,10 +23,9 @@ Be sure to take note of the Qt6 installation directory, as we will need it to co
 Once Qt6 is installed, to build and run `qtk` on Ubuntu -
 ```bash
 sudo apt update -y && sudo apt install freeglut3-dev libassimp-dev cmake build-essential git
-git clone https://gitlab.com/shaunrd0/qtk && cd qtk
+git clone https://gitlab.com/shaunrd0/qtk
-mkdir build && cd build
+cmake -DCMAKE_PREFIX_PATH=$HOME/Qt/6.3.1/gcc_64 -S qtk/ -B qtk/build/ && cmake --build qtk/build/ -j $(nprocs)
-cmake .. -DCMAKE_PREFIX_PATH=$HOME/Qt6/6.2.3/gcc_64 && cmake --build .
+./qtk/build/qtk
-./qtk
 ```
 
 You can fly around the scene if you hold the right mouse button and use WASD.

src/meshrenderer.h

@@ -37,7 +37,8 @@ public:
 
   // Shader settings
   inline void setShaderVertex(const std::string & vert) { mVertexShader = vert;}
-  inline void setShaderFragment(const std::string & frag) { mFragmentShader = frag;}
+  inline void setShaderFragment(const std::string & frag)
+  { mFragmentShader = frag;}
   void setShaders(const std::string & vert, const std::string & frag);
 
   template <typename T>

src/model.cpp

@@ -11,6 +11,7 @@
 
 #include <scene.h>
 #include <texture.h>
+#include <resourcemanager.h>
 
 #include <model.h>
 
@@ -188,6 +189,18 @@ void Model::flipTexture(const std::string & fileName, bool flipX, bool flipY)
  * Model Private Member Functions
  ******************************************************************************/
 
+/**
+ * Loads a model in .obj, .fbx, .gltf, and other formats
+ * For a full list of formats see assimp documentation:
+ *  https://github.com/assimp/assimp/blob/master/doc/Fileformats.md
+ *
+ * Models should not be loaded into Qt resource system
+ * Instead pass an *absolute* path to this function
+ * Relative paths will break if Qtk is executed from different locations
+ * See resourcemanager.h for an example of how qtk handles this
+ *
+ * @param path Absolute path to a model .obj or other format accepted by assimp
+ */
 void Model::loadModel(const std::string & path)
 {
   Assimp::Importer import;
@@ -195,13 +208,14 @@ void Model::loadModel(const std::string & path)
   // JIC a relative path was used, get the absolute file path
   QFileInfo info(path.c_str());
   info.makeAbsolute();
-  std::string temp = info.absoluteFilePath().toStdString();
+  mDirectory = path[0] == ':' ? RM::getPath(path)
+      : info.absoluteFilePath().toStdString();
 
   // Import the model, converting non-triangular geometry to triangles
   // + And flipping texture UVs, etc..
   // Assimp options: http://assimp.sourceforge.net/lib_html/postprocess_8h.html
   const aiScene * scene =
-      import.ReadFile(temp, aiProcess_Triangulate
+      import.ReadFile(mDirectory, aiProcess_Triangulate
                             | aiProcess_FlipUVs
                             | aiProcess_GenSmoothNormals
                             | aiProcess_CalcTangentSpace
@@ -216,7 +230,7 @@ void Model::loadModel(const std::string & path)
     return;
   }
   // If there were no errors, find the directory that contains this model
-  mDirectory = path.substr(0, path.find_last_of('/'));
+  mDirectory = mDirectory.substr(0, mDirectory.find_last_of('/'));
 
   // Pass the pointers to the root node and the scene to recursive function
   // + Base case breaks when no nodes left to process on model

src/resourcemanager.cpp

@@ -0,0 +1,13 @@
+/*##############################################################################
+## Author: Shaun Reed                                                         ##
+## Legal: All Content (c) 2022 Shaun Reed, all rights reserved                ##
+## About: Manage files and resources used by qtk                              ##
+##                                                                            ##
+## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com | GitHub: shaunrd0   ##
+##############################################################################*/
+
+#include "resourcemanager.h"
+
+std::string RM::resourcesDir =
+    std::string(__FILE__).substr(0, std::string(__FILE__).find("src/"))
+    + "resources/";

src/resourcemanager.h

@@ -0,0 +1,35 @@
+/*##############################################################################
+## Author: Shaun Reed                                                         ##
+## Legal: All Content (c) 2022 Shaun Reed, all rights reserved                ##
+## About: Manage files and resources used by qtk                              ##
+##                                                                            ##
+## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com | GitHub: shaunrd0   ##
+##############################################################################*/
+
+#include <string>
+
+#ifndef QTK_RESOURCEMANAGER_H
+#define QTK_RESOURCEMANAGER_H
+
+typedef class ResourceManager {
+public:
+
+  /**
+   * Takes a path using qrc format and constructs full system path to qtk assets
+   * Qrc format prefix ':/' is trimmed from the path for the caller
+   * Assets used with RM may (or may not) appear in qtk/resources.qrc
+   *
+   * @param path Path relative to qtk/resources/; ie) ':/models/backpack/backpack.obj'
+   *    An asset at location qtk/resources/path/to/asset.obj
+   *    Should be given in qrc format: ':/path/to/asset.obj'
+   * @return Absoulte system path to a qtk asset
+   */
+  static std::string getPath(const std::string & path) {
+    // Only construct qtk resource path if in qrc format; else return it as-is
+    return path[0] == ':' ? resourcesDir + path.substr(2) : path;
+  }
+
+  static std::string resourcesDir;
+} RM;
+
+#endif //QTK_RESOURCEMANAGER_H

src/scene.cpp

@@ -10,6 +10,7 @@
 #include <texture.h>
 #include <meshrenderer.h>
 #include <model.h>
+#include <resourcemanager.h>
 
 #include <scene.h>
 
@@ -151,42 +152,31 @@ void Scene::init()
   //
   // Model loading
 
-  mModels.push_back(new Model("backpack",
+  mModels.push_back(new Model("backpack", ":/models/backpack/backpack.obj"));
-                              "../resources/models/backpack/backpack.obj"));
   // Sometimes model textures need flipped in certain directions
   mModels.back()->flipTexture("diffuse.jpg", false, true);
   mModels.back()->mTransform.setTranslation(0.0f, 0.0f, -10.0f);
 
-  mModels.push_back(
+  mModels.push_back(new Model("bird", ":/models/bird/bird.obj"));
-      new Model("bird",
-                "../resources/models/bird/bird.obj"));
   mModels.back()->mTransform.setTranslation(2.0f, 2.0f, -10.0f);
   // Sometimes the models are very large
   mModels.back()->mTransform.scale(0.0025f);
   mModels.back()->mTransform.rotate(-110.0f, 0.0f, 1.0f, 0.0f);
 
-  mModels.push_back(new Model("lion",
+  mModels.push_back(new Model("lion", ":/models/lion/lion.obj"));
-                              "../resources/models/lion/lion.obj"));
   mModels.back()->mTransform.setTranslation(-3.0f, -1.0f, -10.0f);
   mModels.back()->mTransform.scale(0.15f);
 
-  mModels.push_back(
+  mModels.push_back(new Model("alien", ":/models/alien-hominid/alien.obj"));
-      new Model("alien",
-                "../resources/models/alien-hominid/alien.obj"));
   mModels.back()->mTransform.setTranslation(2.0f, -1.0f, -5.0f);
   mModels.back()->mTransform.scale(0.15f);
 
-  mModels.push_back(
+  mModels.push_back(new Model("scythe", ":/models/scythe/scythe.obj"));
-      new Model("scythe",
-                "../resources/models/scythe/scythe.obj")
-  );
   mModels.back()->mTransform.setTranslation(-6.0f, 0.0f, -10.0f);
   mModels.back()->mTransform.rotate(-90.0f, 1.0f, 0.0f, 0.0f);
   mModels.back()->mTransform.rotate(90.0f, 0.0f, 1.0f, 0.0f);
 
-  mModels.push_back(
+  mModels.push_back(new Model("masterChief", ":/models/spartan/spartan.obj"));
-      new Model("masterChief",
-                "../resources/models/spartan/spartan.obj"));
   mModels.back()->mTransform.setTranslation(-1.5f, 0.5f, -2.0f);
 
 
@@ -204,9 +194,9 @@ void Scene::init()
   mMeshes.back()->init();
 
   mModels.push_back(
-      new Model("alienTest",
+      new Model("alienTest", ":/models/alien-hominid/alien.obj",
-                "../resources/models/alien-hominid/alien.obj",
+                ":/model-specular.vert", ":/model-specular.frag")
-                ":/model-specular.vert", ":/model-specular.frag"));
+  );
   mModels.back()->mTransform.setTranslation(3.0f, -1.0f, 10.0f);
   mModels.back()->mTransform.scale(0.15f);
   mModels.back()->setUniform("uMaterial.ambient", QVector3D(1.0f, 1.0f, 1.0f));
@@ -224,7 +214,8 @@ void Scene::init()
 
   // Test spartan Model with phong lighting, specular and normal mapping
   mMeshes.push_back(
-      new MeshRenderer("spartanTestLight", Triangle(QTK_DRAW_ELEMENTS)));
+      new MeshRenderer("spartanTestLight", Triangle(QTK_DRAW_ELEMENTS))
+  );
   mMeshes.back()->mTransform.setTranslation(1.0f, 1.5f, 10.0f);
   mMeshes.back()->mTransform.scale(0.25f);
   // This function changes values we have allocated in a buffer, so init() after
@@ -232,9 +223,9 @@ void Scene::init()
   mMeshes.back()->init();
 
   mModels.push_back(
-      new Model("spartanTest",
+      new Model("spartanTest", ":/models/spartan/spartan.obj",
-                "../resources/models/spartan/spartan.obj",
+                ":/model-normals.vert", ":/model-normals.frag")
-                ":/model-normals.vert", ":/model-normals.frag"));
+  );
   mModels.back()->mTransform.setTranslation(0.0f, -1.0f, 10.0f);
   mModels.back()->mTransform.scale(2.0f);
   mModels.back()->setUniform("uMaterial.ambient", QVector3D(1.0f, 1.0f, 1.0f));