From 43e25b262887544dd8931b2e3e6617a62fa355b4 Mon Sep 17 00:00:00 2001
From: Derek Christ <christ.derek@gmail.com>
Date: Sat, 22 Oct 2022 22:05:24 +0200
Subject: [PATCH] Refactor shaders

---
 ...stprocessing.frag => post_processing.frag} |   0
 ...stprocessing.vert => post_processing.vert} |   0
 .../{basic.frag => standard_material.frag}    |   0
 .../{basic.vert => standard_material.vert}    |   0
 src/CMakeLists.txt                            |   2 +-
 src/Controller.cpp                            |  50 +++---
 src/Controller.h                              |  17 +-
 src/FrameBuffer.cpp                           |  17 +-
 src/FrameBuffer.h                             |   6 +-
 src/Light.cpp                                 |  38 ++---
 src/Light.h                                   |  12 +-
 src/Scene.cpp                                 |  49 ++----
 src/Scene.h                                   |   9 +-
 src/{ShaderProgram.cpp => ShaderProgram_.cpp} |  40 ++---
 src/{ShaderProgram.h => ShaderProgram_.h}     |  18 +--
 src/gltf_loader.cpp                           |  16 +-
 src/gltf_loader.h                             |   1 +
 src/material.cpp                              |  10 +-
 src/material.h                                |  10 +-
 src/render.h                                  |  43 ++++++
 src/resources/CubeMap.cpp                     |   2 +-
 src/shader.cpp                                | 146 ++++++++++++++++++
 src/shader.h                                  |  50 ++++++
 23 files changed, 378 insertions(+), 158 deletions(-)
 rename data/shaders/{postprocessing.frag => post_processing.frag} (100%)
 rename data/shaders/{postprocessing.vert => post_processing.vert} (100%)
 rename data/shaders/{basic.frag => standard_material.frag} (100%)
 rename data/shaders/{basic.vert => standard_material.vert} (100%)
 rename src/{ShaderProgram.cpp => ShaderProgram_.cpp} (77%)
 rename src/{ShaderProgram.h => ShaderProgram_.h} (59%)
 create mode 100644 src/render.h
 create mode 100644 src/shader.cpp
 create mode 100644 src/shader.h

diff --git a/data/shaders/postprocessing.frag b/data/shaders/post_processing.frag
similarity index 100%
rename from data/shaders/postprocessing.frag
rename to data/shaders/post_processing.frag
diff --git a/data/shaders/postprocessing.vert b/data/shaders/post_processing.vert
similarity index 100%
rename from data/shaders/postprocessing.vert
rename to data/shaders/post_processing.vert
diff --git a/data/shaders/basic.frag b/data/shaders/standard_material.frag
similarity index 100%
rename from data/shaders/basic.frag
rename to data/shaders/standard_material.frag
diff --git a/data/shaders/basic.vert b/data/shaders/standard_material.vert
similarity index 100%
rename from data/shaders/basic.vert
rename to data/shaders/standard_material.vert
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index fc223da..2a8beae 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -2,7 +2,6 @@ add_library(fever_engine
     main.cpp
     Controller.cpp
     Window.cpp
-    ShaderProgram.cpp
     Light.cpp
     Scene.cpp
     FrameBuffer.cpp
@@ -13,6 +12,7 @@ add_library(fever_engine
     gltf_loader.cpp
     material.cpp
     camera.cpp
+    shader.cpp
 )
 
 target_compile_features(fever_engine PUBLIC cxx_std_20)
diff --git a/src/Controller.cpp b/src/Controller.cpp
index b51474f..df76872 100644
--- a/src/Controller.cpp
+++ b/src/Controller.cpp
@@ -2,9 +2,10 @@
 #include "FrameBuffer.h"
 #include "Helper.h"
 #include "Light.h"
-#include "ShaderProgram.h"
 #include "Window.h"
 #include "gltf_loader.h"
+#include "render.h"
+#include "shader.h"
 #include "util/Log.h"
 
 #include <GLFW/glfw3.h>
@@ -22,10 +23,11 @@
 using namespace entt::literals;
 
 Controller::Controller()
-    : m_gameWindow(std::make_shared<Window>()),
+    : m_scene(m_shader_cache),
+      m_gameWindow(std::make_shared<Window>()),
       m_postProcessFrameBuffer(m_gameWindow->dimensions().first,
                                m_gameWindow->dimensions().second,
-                               postProcessingProgram)
+                               post_processing_shader)
 {
     // if (!gltf.cameras.empty()) {
     //     auto const &gltf_camera = gltf.cameras.at(0);
@@ -41,18 +43,20 @@ Controller::Controller()
 
 void Controller::run()
 {
-    updateExposure(postProcessingProgram);
+    updateExposure(post_processing_shader);
 
-    // m_camera->translate(glm::vec3(0., .5, 2.));
+    entt::hashed_string shader_hash (Material::SHADER_NAME.data());
+    auto standard_material_shader =
+        m_shader_cache.load(shader_hash, Material::SHADER_NAME).first->second;
 
     DirectionalLight directional_light(
         DirectionalLight::Prototype("", glm::vec3(-0.2, -1.0, -0.3), glm::vec3(1.0f), 5.f),
-        &defaultProgram);
+        standard_material_shader.handle().get());
     directional_light.setActive(true);
 
     PointLight point_light(
         PointLight::Prototype("", "", glm::vec3(4.0, 1.0, 6.0), glm::vec3(1.0F), 3.0F),
-        &defaultProgram);
+        standard_material_shader.handle().get());
     point_light.setActive(true);
 
     Log::logger().info("Startup complete. Enter game loop.");
@@ -62,8 +66,8 @@ void Controller::run()
         // --- Timing ---
         limit_framerate();
 
-        // --- Update game ---
-        m_gameWindow->clear_mouse_cursor_input(); // MOVE DOWN AGAIN!
+        // --- Check events, handle input ---
+        m_gameWindow->clear_mouse_cursor_input();
         glfwPollEvents();
 
         auto const &key_input = m_gameWindow->key_input();
@@ -72,7 +76,10 @@ void Controller::run()
         static constexpr auto MICROSECONDS_PER_SECOND = 1'000'000;
         m_scene.update(
             std::chrono::microseconds(static_cast<unsigned>(m_deltaTime * MICROSECONDS_PER_SECOND)),
-            key_input,mouse_cursor_input, m_gameWindow->aspectRatio());
+            key_input,
+            mouse_cursor_input,
+            m_gameWindow->aspectRatio(),
+            m_gameWindow->cursor_catched());
 
         // --- Render and buffer swap ---
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
@@ -80,7 +87,7 @@ void Controller::run()
         m_postProcessFrameBuffer.bind();
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
-        m_scene.draw(&defaultProgram);
+        Render::render(m_scene.registry());
 
         Framebuffer::unbind();
         m_postProcessFrameBuffer.drawOnEntireScreen();
@@ -92,19 +99,6 @@ void Controller::run()
             m_gameWindow->update_dimensions();
             update_window_dimensions();
         }
-
-        // --- Check events, handle input ---
-        // m_gameWindow->clear_mouse_cursor_input();
-        // glfwPollEvents();
-
-        // auto const &key_input = m_gameWindow->key_input();
-        // auto const &mouse_cursor_input = m_gameWindow->mouse_cursor_input();
-
-        // m_camera->updatePositionFromKeyboardInput(key_input, (float)m_deltaTime);
-
-        // if (m_gameWindow->cursor_catched()) {
-        //     m_camera->updateDirectionFromMouseInput(mouse_cursor_input);
-        // }
     }
 }
 
@@ -137,9 +131,9 @@ void Controller::update_window_dimensions()
     m_postProcessFrameBuffer.changeDimensions(dimensions.first, dimensions.second);
 }
 
-void Controller::updateExposure(ShaderProgram &shaderProgram) const
+void Controller::updateExposure(Shader &shader) const
 {
-    shaderProgram.bind();
-    shaderProgram.setUniform("u_exposure", m_exposure);
-    ShaderProgram::unbind();
+    shader.bind();
+    shader.set_uniform("u_exposure", m_exposure);
+    Shader::unbind();
 }
diff --git a/src/Controller.h b/src/Controller.h
index a4e3423..189ffda 100644
--- a/src/Controller.h
+++ b/src/Controller.h
@@ -1,13 +1,14 @@
 #pragma once
 
 #include "FrameBuffer.h"
-#include "ShaderProgram.h"
 #include "Scene.h"
+#include "shader.h"
 
 #include <glm/glm.hpp>
 #include <memory>
-#include <vector>
 #include <unordered_map>
+#include <vector>
+#include <entt/entt.hpp>
 
 class Window;
 class Scene;
@@ -21,21 +22,21 @@ public:
 
     void run();
 
-    void updateExposure(ShaderProgram &shaderProgram) const;
+    void updateExposure(Shader &shader) const;
 
 private:
     void limit_framerate();
     void update_window_dimensions();
 
     std::shared_ptr<Window> m_gameWindow;
-
-    ShaderProgram defaultProgram{{"defaultProgram", "data/shaders/basic.vert", "data/shaders/basic.frag"}};
-    ShaderProgram skyboxProgram{{"skyboxProgram", "data/shaders/skybox.vert", "data/shaders/skybox.frag"}};
-    ShaderProgram postProcessingProgram{
-        {"postProcessingProgram", "data/shaders/postprocessing.vert", "data/shaders/postprocessing.frag"}};
+    
+    Shader skybox_shader{"skybox", "data/shaders"};
+    Shader post_processing_shader{"post_processing", "data/shaders"};
 
     Framebuffer m_postProcessFrameBuffer;
 
+    entt::resource_cache<Shader, ShaderLoader> m_shader_cache;
+
     static constexpr unsigned MAX_FPS = 60;
 
     Scene m_scene;
diff --git a/src/FrameBuffer.cpp b/src/FrameBuffer.cpp
index 1e34378..0db83cc 100644
--- a/src/FrameBuffer.cpp
+++ b/src/FrameBuffer.cpp
@@ -1,5 +1,5 @@
 #include "FrameBuffer.h"
-#include "ShaderProgram.h"
+#include "shader.h"
 #include "util/Log.h"
 
 #include <cstddef>
@@ -19,7 +19,7 @@ GLuint Framebuffer::getFBO() const
     return m_FBO;
 }
 
-Framebuffer::Framebuffer(uint32_t width, uint32_t height, ShaderProgram &shaderProgram) : m_shaderProgram(shaderProgram)
+Framebuffer::Framebuffer(uint32_t width, uint32_t height, Shader &shader) : m_shader(shader)
 {
     glGenFramebuffers(1, &m_FBO);
 
@@ -46,12 +46,11 @@ void Framebuffer::drawOnEntireScreen() const
     glGetIntegerv(GL_POLYGON_MODE, &wireframe);
     glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 
-    m_shaderProgram.bind();
+    m_shader.bind();
     glActiveTexture(GL_TEXTURE0);
     glBindTexture(GL_TEXTURE_2D, getTextureId());
 
-    GLint location = glGetUniformLocation(m_shaderProgram.getShaderProgramId(), "u_texture");
-    glUniform1i(location, 0);
+    m_shader.set_uniform("u_texture", 0);
 
     // A VAO is necessary although no data is stored in it
     GLuint temp_vao;
@@ -61,7 +60,7 @@ void Framebuffer::drawOnEntireScreen() const
     glBindVertexArray(0);
 
     glPolygonMode(GL_FRONT_AND_BACK, static_cast<GLenum>(wireframe));
-    m_shaderProgram.unbind();
+    m_shader.unbind();
 }
 
 void Framebuffer::changeDimensions(uint32_t width, uint32_t height)
@@ -108,7 +107,7 @@ void Framebuffer::generateTextures(uint32_t width, uint32_t height)
 
 void Framebuffer::setExposureCorrection(bool exposureCorrection) const
 {
-    m_shaderProgram.bind();
-    m_shaderProgram.setUniform("u_exposureCorrection", exposureCorrection);
-    m_shaderProgram.unbind();
+    m_shader.bind();
+    m_shader.set_uniform("u_exposureCorrection", exposureCorrection);
+    m_shader.unbind();
 }
diff --git a/src/FrameBuffer.h b/src/FrameBuffer.h
index 7ffd7d3..e0d7ae7 100644
--- a/src/FrameBuffer.h
+++ b/src/FrameBuffer.h
@@ -2,12 +2,12 @@
 
 #include <glad/gl.h>
 
-class ShaderProgram;
+class Shader;
 
 class Framebuffer
 {
 public:
-    Framebuffer(uint32_t width, uint32_t height, ShaderProgram &shaderProgram);
+    Framebuffer(uint32_t width, uint32_t height, Shader &shader);
     ~Framebuffer();
 
     void bind() const;
@@ -29,5 +29,5 @@ private:
     GLuint m_depthStencilBuffer;
     GLuint m_FBO;
 
-    ShaderProgram &m_shaderProgram;
+    Shader &m_shader;
 };
diff --git a/src/Light.cpp b/src/Light.cpp
index 65d9893..5fc8fa1 100644
--- a/src/Light.cpp
+++ b/src/Light.cpp
@@ -1,12 +1,12 @@
 #include "Light.h"
-#include "ShaderProgram.h"
+#include "shader.h"
 
 #include <string>
 
 uint32_t Light::s_idCounter = 0;
 
-Light::Light(const std::string &name, glm::vec3 color, float intensity, ShaderProgram *shaderProgram)
-    : m_shaderProgram(shaderProgram), m_intensity(intensity), m_lightColor(color * intensity)
+Light::Light(const std::string &name, glm::vec3 color, float intensity, Shader *shader)
+    : m_shader(shader), m_intensity(intensity), m_lightColor(color * intensity)
 {
     m_id = s_idCounter++;
 }
@@ -18,9 +18,9 @@ glm::vec3 Light::getColor()
     return m_lightColor;
 }
 
-void Light::setShaderProgram(ShaderProgram *shaderProgram)
+void Light::setShader(Shader *shader)
 {
-    this->m_shaderProgram = shaderProgram;
+    this->m_shader = shader;
     update();
 }
 
@@ -41,21 +41,21 @@ void Light::setActive(bool active)
     update();
 }
 
-PointLight::PointLight(Prototype prototype, ShaderProgram *shaderProgram)
-    : Light(prototype.name, prototype.color, prototype.intensity, shaderProgram), m_position(prototype.position)
+PointLight::PointLight(Prototype prototype, Shader *shader)
+    : Light(prototype.name, prototype.color, prototype.intensity, shader), m_position(prototype.position)
 {
     update();
 }
 
 void PointLight::update()
 {
-    m_shaderProgram->bind();
+    m_shader->bind();
 
-    m_shaderProgram->setUniform((getStructMemberName() + "isActive").c_str(), m_isActive);
-    m_shaderProgram->setUniform((getStructMemberName() + "position").c_str(), m_position);
-    m_shaderProgram->setUniform((getStructMemberName() + "color").c_str(), m_lightColor);
+    m_shader->set_uniform((getStructMemberName() + "isActive").c_str(), m_isActive);
+    m_shader->set_uniform((getStructMemberName() + "position").c_str(), m_position);
+    m_shader->set_uniform((getStructMemberName() + "color").c_str(), m_lightColor);
 
-    m_shaderProgram->unbind();
+    m_shader->unbind();
 }
 
 std::string PointLight::getStructMemberName()
@@ -76,21 +76,21 @@ void PointLight::setPosition(glm::vec3 position)
     update();
 }
 
-DirectionalLight::DirectionalLight(Prototype prototype, ShaderProgram *shaderProgram)
-    : Light(prototype.name, prototype.color, prototype.intensity, shaderProgram), m_direction(prototype.direction)
+DirectionalLight::DirectionalLight(Prototype prototype, Shader *shader)
+    : Light(prototype.name, prototype.color, prototype.intensity, shader), m_direction(prototype.direction)
 {
     update();
 }
 
 void DirectionalLight::update()
 {
-    m_shaderProgram->bind();
+    m_shader->bind();
 
-    m_shaderProgram->setUniform("u_directionalLight.isActive", m_isActive);
-    m_shaderProgram->setUniform("u_directionalLight.direction", m_direction);
-    m_shaderProgram->setUniform("u_directionalLight.color", m_lightColor);
+    m_shader->set_uniform("u_directionalLight.isActive", m_isActive);
+    m_shader->set_uniform("u_directionalLight.direction", m_direction);
+    m_shader->set_uniform("u_directionalLight.color", m_lightColor);
 
-    m_shaderProgram->unbind();
+    m_shader->unbind();
 }
 
 void DirectionalLight::setDirection(glm::vec3 direction)
diff --git a/src/Light.h b/src/Light.h
index 1128e19..e1eba72 100644
--- a/src/Light.h
+++ b/src/Light.h
@@ -3,7 +3,7 @@
 #include <glm/glm.hpp>
 #include <string>
 
-class ShaderProgram;
+class Shader;
 
 class Light
 {
@@ -21,7 +21,7 @@ public:
         float intensity;
     };
 
-    Light(const std::string &name, glm::vec3 color, float intensity, ShaderProgram *shaderProgram);
+    Light(const std::string &name, glm::vec3 color, float intensity, Shader *shader);
     virtual ~Light() = 0;
 
     virtual void update() = 0;
@@ -29,12 +29,12 @@ public:
     void setActive(bool active);
     void setColor(glm::vec3 color);
     void setIntensity(float intensity);
-    void setShaderProgram(ShaderProgram *shaderProgram);
+    void setShader(Shader *shader);
 
     glm::vec3 getColor();
 
 protected:
-    ShaderProgram *m_shaderProgram;
+    Shader *m_shader;
 
     uint32_t m_id;
     static uint32_t s_idCounter;
@@ -59,7 +59,7 @@ public:
         glm::vec3 position;
     };
 
-    PointLight(Prototype prototype, ShaderProgram *shaderProgram);
+    PointLight(Prototype prototype, Shader *shader);
     ~PointLight() override = default;
 
     void setPosition(glm::vec3 position);
@@ -84,7 +84,7 @@ public:
         glm::vec3 direction;
     };
 
-    DirectionalLight(Prototype prototype, ShaderProgram *shaderProgram);
+    DirectionalLight(Prototype prototype, Shader *shader);
     ~DirectionalLight() override = default;
 
     void setDirection(glm::vec3 direction);
diff --git a/src/Scene.cpp b/src/Scene.cpp
index 249c0ef..4155f10 100644
--- a/src/Scene.cpp
+++ b/src/Scene.cpp
@@ -1,20 +1,21 @@
 #include "Scene.h"
-#include "ShaderProgram.h"
 #include "camera.h"
 #include "mesh.h"
 #include "name.h"
 #include "relationship.h"
+#include "shader.h"
 #include "transform.h"
 #include "util/Log.h"
 
 using namespace entt::literals;
 
 // TODO: make scene initialization part of gltf loader as seen in bevy
-Scene::Scene()
+Scene::Scene(entt::resource_cache<Shader, ShaderLoader> &shader_cache)
 {
     GltfLoader loader{.image_cache = m_image_cache,
                       .material_cache = m_material_cache,
                       .mesh_cache = m_mesh_cache,
+                      .shader_cache = shader_cache,
                       .gltf_mesh_cache = m_gltf_mesh_cache,
                       .gltf_node_cache = m_gltf_node_cache,
                       .gltf_scene_cache = m_gltf_scene_cache};
@@ -92,16 +93,16 @@ Scene::Scene()
     // Spawn the camera
     auto entity = m_registry.create();
     m_registry.emplace<Name>(entity, "Camera");
-    m_registry.emplace<Transform>(entity, Transform{.translation = glm::vec3(0.0, 0.5, -1.0)});
+    m_registry.emplace<Transform>(entity, Transform{.translation = glm::vec3(0.0, 0.25, -1.0)});
     m_registry.emplace<GlobalTransform>(entity, GlobalTransform{});
-    m_registry.emplace<Camera>(entity,
-                               Camera{.projection = Camera::Perspective{}});
+    m_registry.emplace<Camera>(entity, Camera{.projection = Camera::Perspective{}});
 }
 
 void Scene::update(std::chrono::duration<float> delta,
                    KeyInput const &key_input,
                    MouseCursorInput const &mouse_cursor_input,
-                   float aspect_ratio)
+                   float aspect_ratio,
+                   bool cursor_catched)
 {
     {
         // Update GlobalTransform components
@@ -138,38 +139,10 @@ void Scene::update(std::chrono::duration<float> delta,
         }
     }
 
-    Camera::keyboard_movement(m_registry, key_input, delta);
-    Camera::mouse_orientation(m_registry, mouse_cursor_input);
     Camera::aspect_ratio_update(m_registry, aspect_ratio);
-}
-
-void Scene::draw(ShaderProgram *shaderprogram) const
-{
-    auto mesh_view = m_registry.view<GpuMesh const, GpuMaterial const, GlobalTransform const>();
-    auto camera_view = m_registry.view<Camera const, GlobalTransform const>();
-    auto camera_entity = camera_view.front();
-    auto [camera, camera_transform] = camera_view.get(camera_entity);
-    glm::mat4 view_projection_matrix =
-        camera.projection_matrix() * Camera::view_matrix(camera_transform);
-
-    for (auto [entity, mesh, material, transform] : mesh_view.each()) {
-        shaderprogram->bind();
-
-        // Bind textures
-        material.bind(*shaderprogram);
-
-        // Bind modelview matrix uniform
-        {
-            glm::mat4 modelViewProj = view_projection_matrix * transform.transform;
-            shaderprogram->setUniform("u_modelViewProjMatrix", modelViewProj);
-            shaderprogram->setUniform("u_modelMatrix", transform.transform);
-            shaderprogram->setUniform("u_viewPosition", camera_transform.position());
-        }
-
-        glBindVertexArray(mesh.vao);
-        glDrawElements(GL_TRIANGLES, mesh.indices_count, mesh.indices_type, nullptr);
-        glBindVertexArray(0);
-
-        ShaderProgram::unbind();
+    Camera::keyboard_movement(m_registry, key_input, delta);
+    if (cursor_catched) {
+        Camera::mouse_orientation(m_registry, mouse_cursor_input);
     }
+    
 }
diff --git a/src/Scene.h b/src/Scene.h
index 20e4d6d..e5c1330 100644
--- a/src/Scene.h
+++ b/src/Scene.h
@@ -8,19 +8,20 @@
 #include <chrono>
 #include <entt/entt.hpp>
 
-class ShaderProgram;
+class Shader;
 
 class Scene
 {
 public:
-    Scene();
+    Scene(entt::resource_cache<Shader, ShaderLoader> &shader_cache);
 
     void update(std::chrono::duration<float> delta_time,
                 KeyInput const &key_input,
                 MouseCursorInput const &mouse_cursor_input,
-                float aspect_ratio);
+                float aspect_ratio,
+                bool cursor_catched);
 
-    void draw(ShaderProgram *shaderprogram) const;
+    auto registry() -> entt::registry & { return m_registry; }
 
 private:
     entt::registry m_registry;
diff --git a/src/ShaderProgram.cpp b/src/ShaderProgram_.cpp
similarity index 77%
rename from src/ShaderProgram.cpp
rename to src/ShaderProgram_.cpp
index 6023160..dff1e18 100644
--- a/src/ShaderProgram.cpp
+++ b/src/ShaderProgram_.cpp
@@ -7,8 +7,8 @@
 
 ShaderProgram::ShaderProgram(Prototype prototype) : m_shaderProgramId(glCreateProgram())
 {
-    std::string vertexShaderSource = parse(prototype.vertexPath).value();
-    std::string fragmentShaderSource = parse(prototype.fragmentPath).value();
+    std::string vertexShaderSource = parse(prototype.vertexPath);
+    std::string fragmentShaderSource = parse(prototype.fragmentPath);
 
     GLuint vertexShader = compile(vertexShaderSource, GL_VERTEX_SHADER);
     GLuint fragmentShader = compile(fragmentShaderSource, GL_FRAGMENT_SHADER);
@@ -21,7 +21,9 @@ ShaderProgram::ShaderProgram(Prototype prototype) : m_shaderProgramId(glCreatePr
     GLint isLinked = 0;
     glGetProgramiv(m_shaderProgramId, GL_LINK_STATUS, &isLinked);
     if (isLinked == 0) {
-        Log::logger().warn(R"(Failed to link shaderProgram "{}", "{}")", prototype.vertexPath, prototype.fragmentPath);
+        Log::logger().warn(R"(Failed to link shaderProgram "{}", "{}")",
+                           prototype.vertexPath,
+                           prototype.fragmentPath);
     }
 
 #ifdef NDEBUG
@@ -50,19 +52,17 @@ void ShaderProgram::unbind()
     glUseProgram(0);
 }
 
-auto ShaderProgram::parse(const std::filesystem::path &path) -> std::optional<std::string>
+auto ShaderProgram::parse(const std::filesystem::path &path) -> std::string
 {
-    std::fstream shaderfile;
-    shaderfile.open(path, std::ios::in);
+    std::fstream file;
+    file.open(path, std::ios::in);
 
-    if (!shaderfile.is_open()) {
-        Log::logger().warn("Shader \"{}\" not found", path.c_str());
-        return {};
+    if (!file.is_open()) {
+        Log::logger().critical(R"(Shader "{}" not found!)", path.string());
+        std::terminate();
     }
 
-    std::string contents((std::istreambuf_iterator<char>(shaderfile)), (std::istreambuf_iterator<char>()));
-
-    return contents;
+    return {(std::istreambuf_iterator<char>(file)), (std::istreambuf_iterator<char>())};
 }
 
 auto ShaderProgram::compile(const std::string &shaderSource, GLenum type) -> GLuint
@@ -108,49 +108,49 @@ auto ShaderProgram::retrieveUniformLocation(std::string_view uniform_name) const
     return location;
 }
 
-void ShaderProgram::setUniform(const std::string &name, bool value) const
+void ShaderProgram::set_uniform(const std::string &name, bool value) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform1i(location, (int)value);
 }
 
-void ShaderProgram::setUniform(const std::string &name, int value) const
+void ShaderProgram::set_uniform(const std::string &name, int value) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform1i(location, value);
 }
 
-void ShaderProgram::setUniform(const std::string &name, unsigned int value) const
+void ShaderProgram::set_uniform(const std::string &name, unsigned int value) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform1ui(location, value);
 }
 
-void ShaderProgram::setUniform(const std::string &name, float value) const
+void ShaderProgram::set_uniform(const std::string &name, float value) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform1f(location, value);
 }
 
-void ShaderProgram::setUniform(const std::string &name, glm::vec2 vector) const
+void ShaderProgram::set_uniform(const std::string &name, glm::vec2 vector) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform2f(location, vector.x, vector.y);
 }
 
-void ShaderProgram::setUniform(const std::string &name, glm::vec3 vector) const
+void ShaderProgram::set_uniform(const std::string &name, glm::vec3 vector) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniform3f(location, vector.x, vector.y, vector.z);
 }
 
-void ShaderProgram::setUniform(const std::string &name, glm::mat3 matrix) const
+void ShaderProgram::set_uniform(const std::string &name, glm::mat3 matrix) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniformMatrix3fv(location, 1, GL_FALSE, glm::value_ptr(matrix));
 }
 
-void ShaderProgram::setUniform(const std::string &name, glm::mat4 matrix) const
+void ShaderProgram::set_uniform(const std::string &name, glm::mat4 matrix) const
 {
     GLint location = retrieveUniformLocation(name);
     glUniformMatrix4fv(location, 1, GL_FALSE, glm::value_ptr(matrix));
diff --git a/src/ShaderProgram.h b/src/ShaderProgram_.h
similarity index 59%
rename from src/ShaderProgram.h
rename to src/ShaderProgram_.h
index eb3177d..304beca 100644
--- a/src/ShaderProgram.h
+++ b/src/ShaderProgram_.h
@@ -26,19 +26,19 @@ public:
     auto retrieveUniformLocation(std::string_view uniform_name) const -> GLint;
 
     // May be rewritten...
-    void setUniform(const std::string &name, bool value) const;
-    void setUniform(const std::string &name, int value) const;
-    void setUniform(const std::string &name, unsigned int value) const;
-    void setUniform(const std::string &name, float value) const;
-    void setUniform(const std::string &name, glm::vec2 vector) const;
-    void setUniform(const std::string &name, glm::vec3 vector) const;
-    void setUniform(const std::string &name, glm::mat3 matrix) const;
-    void setUniform(const std::string &name, glm::mat4 matrix) const;
+    void set_uniform(const std::string &name, bool value) const;
+    void set_uniform(const std::string &name, int value) const;
+    void set_uniform(const std::string &name, unsigned int value) const;
+    void set_uniform(const std::string &name, float value) const;
+    void set_uniform(const std::string &name, glm::vec2 vector) const;
+    void set_uniform(const std::string &name, glm::vec3 vector) const;
+    void set_uniform(const std::string &name, glm::mat3 matrix) const;
+    void set_uniform(const std::string &name, glm::mat4 matrix) const;
 
     auto getShaderProgramId() const -> GLuint;
 
 private:
-    static auto parse(const std::filesystem::path &path) -> std::optional<std::string>;
+    static auto parse(const std::filesystem::path &path) -> std::string;
     static auto compile(const std::string &shaderSource, GLenum type) -> GLuint;
 
     GLuint m_shaderProgramId;
diff --git a/src/gltf_loader.cpp b/src/gltf_loader.cpp
index 7aabd4b..7162276 100644
--- a/src/gltf_loader.cpp
+++ b/src/gltf_loader.cpp
@@ -1,6 +1,6 @@
 #include "gltf_loader.h"
-#include "util/Log.h"
 #include "definitions/attribute_locations.h"
+#include "util/Log.h"
 
 #include <iterator>
 
@@ -73,7 +73,8 @@ static auto load_material(fx::gltf::Material const &material,
                           fx::gltf::Document const &gltf,
                           std::filesystem::path const &document_path,
                           entt::resource_cache<Material> &material_cache,
-                          entt::resource_cache<Image> &image_cache) -> entt::resource<Material>
+                          entt::resource_cache<Image> &image_cache,
+                          entt::resource_cache<Shader, ShaderLoader> &shader_cache) -> entt::resource<Material>
 {
     auto base_color_texture_id = material.pbrMetallicRoughness.baseColorTexture.index;
     auto normal_texture_id = material.normalTexture.index;
@@ -92,6 +93,10 @@ static auto load_material(fx::gltf::Material const &material,
             load_texture(normal_texture, gltf, document_path, Image::ColorFormat::RGB, image_cache);
     }
 
+    entt::hashed_string shader_hash(Material::SHADER_NAME.data());
+    entt::resource<Shader> shader =
+        shader_cache.load(shader_hash, Material::SHADER_NAME).first->second;
+
     if (material.name.empty()) {
         Log::logger().warn("glTF material has no name.");
     }
@@ -100,7 +105,8 @@ static auto load_material(fx::gltf::Material const &material,
     return material_cache
         .load(material_hash,
               Material{.base_color_texture = base_color_image,
-                       .normal_map_texture = normal_map_image})
+                       .normal_map_texture = normal_map_image,
+                       .shader = shader})
         .first->second;
 }
 
@@ -256,8 +262,8 @@ auto GltfLoader::operator()(std::filesystem::path const &document_path) -> resul
     // Load materials
     std::vector<entt::resource<Material>> materials;
     for (auto const &gltf_material : gltf.materials) {
-        entt::resource<Material> material =
-            load_material(gltf_material, gltf, document_path, material_cache, image_cache);
+        entt::resource<Material> material = load_material(
+            gltf_material, gltf, document_path, material_cache, image_cache, shader_cache);
         materials.push_back(material);
     }
 
diff --git a/src/gltf_loader.h b/src/gltf_loader.h
index 9756fc0..186d417 100644
--- a/src/gltf_loader.h
+++ b/src/gltf_loader.h
@@ -55,6 +55,7 @@ struct GltfLoader final
     entt::resource_cache<Image> &image_cache;
     entt::resource_cache<Material> &material_cache;
     entt::resource_cache<Mesh> &mesh_cache;
+    entt::resource_cache<Shader, ShaderLoader> &shader_cache;
 
     entt::resource_cache<GltfMesh> &gltf_mesh_cache;
     entt::resource_cache<GltfNode> &gltf_node_cache;
diff --git a/src/material.cpp b/src/material.cpp
index f0bf21b..d481952 100644
--- a/src/material.cpp
+++ b/src/material.cpp
@@ -1,7 +1,7 @@
 #include "material.h"
-#include "ShaderProgram.h"
+#include "shader.h"
 
-GpuMaterial::GpuMaterial(Material const &material)
+GpuMaterial::GpuMaterial(Material const &material) : shader(material.shader)
 {
     int texture_unit_counter = 0;
 
@@ -17,11 +17,11 @@ GpuMaterial::GpuMaterial(Material const &material)
         normal_map_texture = std::make_pair(GpuImage(material.normal_map_texture.value()), binding);
     }
 }
-void GpuMaterial::bind(ShaderProgram const &shader_program) const
+void GpuMaterial::bind() const
 {
-    auto bind_texture = [&shader_program](auto const &texture) {
+    auto bind_texture = [this](auto const &texture) {
         if (texture.has_value()) {
-            shader_program.setUniform(texture->second.uniform_name, texture->second.texture_unit);
+            shader->set_uniform(texture->second.uniform_name, texture->second.texture_unit);
             glActiveTexture(GL_TEXTURE0 + texture->second.texture_unit);
             glBindTexture(GL_TEXTURE_2D, texture->first.texture);
         }
diff --git a/src/material.h b/src/material.h
index 700f301..f7464c5 100644
--- a/src/material.h
+++ b/src/material.h
@@ -1,23 +1,27 @@
 #pragma once
 
 #include "image.h"
+#include "shader.h"
 
 #include <entt/entt.hpp>
 #include <optional>
 
-class ShaderProgram;
+class Shader;
 
 struct Material
 {
     std::optional<entt::resource<Image>> base_color_texture;
     std::optional<entt::resource<Image>> normal_map_texture;
+
+    static constexpr std::string_view SHADER_NAME{"standard_material"};
+    entt::resource<Shader> shader;
 };
 
 struct GpuMaterial
 {
     GpuMaterial(Material const &material);
 
-    void bind(ShaderProgram const &shader_program) const;
+    void bind() const;
 
     struct Binding
     {
@@ -27,4 +31,6 @@ struct GpuMaterial
 
     std::optional<std::pair<GpuImage, Binding>> base_color_texture;
     std::optional<std::pair<GpuImage, Binding>> normal_map_texture;
+
+    entt::resource<Shader> shader;
 };
diff --git a/src/render.h b/src/render.h
new file mode 100644
index 0000000..fcf3ad2
--- /dev/null
+++ b/src/render.h
@@ -0,0 +1,43 @@
+#pragma once
+
+#include "camera.h"
+#include "material.h"
+#include "mesh.h"
+
+#include <entt/entt.hpp>
+
+namespace Render {
+    
+void render(entt::registry &registry)
+{
+    auto mesh_view = registry.view<GpuMesh const, GpuMaterial const, GlobalTransform const>();
+    auto camera_view = registry.view<Camera const, GlobalTransform const>();
+    auto camera_entity = camera_view.front();
+    auto [camera, camera_transform] = camera_view.get(camera_entity);
+    glm::mat4 view_projection_matrix =
+        camera.projection_matrix() * Camera::view_matrix(camera_transform);
+
+    for (auto [entity, mesh, material, transform] : mesh_view.each()) {
+        auto shader = material.shader;
+        shader->bind();
+
+        // Bind textures
+        material.bind();
+
+        // Bind modelview matrix uniform
+        {
+            glm::mat4 modelViewProj = view_projection_matrix * transform.transform;
+            shader->set_uniform("u_modelViewProjMatrix", modelViewProj);
+            shader->set_uniform("u_modelMatrix", transform.transform);
+            shader->set_uniform("u_viewPosition", camera_transform.position());
+        }
+
+        glBindVertexArray(mesh.vao);
+        glDrawElements(GL_TRIANGLES, mesh.indices_count, mesh.indices_type, nullptr);
+        glBindVertexArray(0);
+
+        Shader::unbind();
+    }
+}
+
+} // namespace Render
diff --git a/src/resources/CubeMap.cpp b/src/resources/CubeMap.cpp
index b33a007..e16e370 100644
--- a/src/resources/CubeMap.cpp
+++ b/src/resources/CubeMap.cpp
@@ -69,7 +69,7 @@ void AbstractCubeMap::bind(ShaderProgram *shaderProgram) const
 {
     std::string uniformName = "u_skybox";
 
-    shaderProgram->setUniform(uniformName, 0);
+    shaderProgram->set_uniform(uniformName, 0);
     glActiveTexture(GL_TEXTURE0);
     glBindTexture(GL_TEXTURE_CUBE_MAP, m_glId);
 }
diff --git a/src/shader.cpp b/src/shader.cpp
new file mode 100644
index 0000000..ec2e66c
--- /dev/null
+++ b/src/shader.cpp
@@ -0,0 +1,146 @@
+#include "shader.h"
+#include "util/Log.h"
+
+#include <fmt/format.h>
+#include <fstream>
+#include <glm/gtc/type_ptr.hpp>
+
+Shader::Shader(std::string_view name, std::filesystem::path const &directory)
+    : program(glCreateProgram())
+{
+    std::filesystem::path vertex_shader_path = directory / name;
+    vertex_shader_path.concat(".vert");
+
+    std::filesystem::path frag_shader_path = directory / name;
+    frag_shader_path.concat(".frag");
+
+    std::string vertex_shader_source = parse(vertex_shader_path);
+    std::string fragment_shader_source = parse(frag_shader_path);
+
+    GLuint vertex_shader = compile(vertex_shader_source, GL_VERTEX_SHADER);
+    GLuint fragment_shader = compile(fragment_shader_source, GL_FRAGMENT_SHADER);
+
+    glAttachShader(program, vertex_shader);
+    glAttachShader(program, fragment_shader);
+
+    glLinkProgram(program);
+
+    GLint linked = 0;
+    glGetProgramiv(program, GL_LINK_STATUS, &linked);
+    
+    if (linked == 0) {
+        Log::logger().warn(R"(Failed to link Shader "{}")", name);
+    }
+
+#ifdef NDEBUG
+    glDetachShader(m_ShaderId, vertexShader);
+    glDetachShader(m_ShaderId, fragmentShader);
+
+    glDeleteShader(vertexShader);
+    glDeleteShader(fragmentShader);
+#endif
+
+    Log::logger().trace(R"(Loaded Shader "{}")", name);
+}
+
+Shader::~Shader()
+{
+    glDeleteProgram(program);
+}
+
+void Shader::bind() const
+{
+    glUseProgram(program);
+}
+
+void Shader::unbind()
+{
+    glUseProgram(0);
+}
+
+auto Shader::parse(const std::filesystem::path &path) -> std::string
+{
+    std::fstream file;
+    file.open(path, std::ios::in);
+
+    if (!file.is_open()) {
+        Log::logger().critical(R"(Shader "{}" not found!)", path.string());
+        std::terminate();
+    }
+
+    return {(std::istreambuf_iterator<char>(file)), (std::istreambuf_iterator<char>())};
+}
+
+auto Shader::compile(std::string_view source, GLenum type) -> GLuint
+{
+    GLuint program = glCreateShader(type);
+    auto const *src = source.data();
+    glShaderSource(program, 1, &src, nullptr);
+    glCompileShader(program);
+
+    int result{};
+    glGetShaderiv(program, GL_COMPILE_STATUS, &result);
+
+    if (result != GL_TRUE) {
+        int length{};
+        glGetShaderiv(program, GL_INFO_LOG_LENGTH, &length);
+
+        std::string message;
+        message.reserve(static_cast<unsigned>(length));
+
+        glGetShaderInfoLog(program, length, &length, message.data());
+        Log::logger().error("Shader compilation failed: {}", message);
+
+        return 0;
+    }
+
+    return program;
+}
+
+auto Shader::retrieveUniformLocation(std::string_view uniform_name) const -> GLint
+{
+    if (uniform_location_cache.find(uniform_name.data()) != uniform_location_cache.end()) {
+        return uniform_location_cache[uniform_name.data()];
+    }
+
+    GLint location = glGetUniformLocation(program, uniform_name.data());
+
+    if (location != -1) {
+        uniform_location_cache[uniform_name.data()] = location;
+    } else {
+        Log::logger().warn(R"(Uniform "{}" not found.)", uniform_name);
+    }
+
+    return location;
+}
+
+template <typename T>
+void Shader::set_uniform(std::string_view name, T value) const
+{
+    GLint location = retrieveUniformLocation(name);
+
+    if constexpr (std::is_same_v<T, bool> || std::is_same_v<T, int>) {
+        glUniform1i(location, (int)value);
+    } else if constexpr (std::is_same_v<T, unsigned>) {
+        glUniform1ui(location, value);
+    } else if constexpr (std::is_same_v<T, float>) {
+        glUniform1f(location, value);
+    } else if constexpr (std::is_same_v<T, glm::vec2>) {
+        glUniform2f(location, value.x, value.y); //NOLINT(cppcoreguidelines-pro-type-union-access)
+    } else if constexpr (std::is_same_v<T, glm::vec3>) {
+        glUniform3f(location, value.x, value.y, value.z); //NOLINT(cppcoreguidelines-pro-type-union-access)
+    } else if constexpr (std::is_same_v<T, glm::mat3>) {
+        glUniformMatrix3fv(location, 1, GL_FALSE, glm::value_ptr(value));
+    } else if constexpr (std::is_same_v<T, glm::mat4>) {
+        glUniformMatrix4fv(location, 1, GL_FALSE, glm::value_ptr(value));
+    }
+}
+
+template void Shader::set_uniform(std::string_view, bool) const;
+template void Shader::set_uniform(std::string_view, int) const;
+template void Shader::set_uniform(std::string_view, unsigned) const;
+template void Shader::set_uniform(std::string_view, float) const;
+template void Shader::set_uniform(std::string_view, glm::vec2) const;
+template void Shader::set_uniform(std::string_view, glm::vec3) const;
+template void Shader::set_uniform(std::string_view, glm::mat3) const;
+template void Shader::set_uniform(std::string_view, glm::mat4) const;
diff --git a/src/shader.h b/src/shader.h
new file mode 100644
index 0000000..64a67fb
--- /dev/null
+++ b/src/shader.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include <filesystem>
+#include <glad/gl.h>
+#include <glm/glm.hpp>
+#include <string_view>
+#include <unordered_map>
+
+struct Shader
+{
+    Shader(std::string_view name, std::filesystem::path const &directory);
+
+    Shader(Shader const &) = delete;
+    auto operator=(Shader const &) -> Shader & = delete;
+
+    Shader(Shader &&other) noexcept : program(other.program) { other.program = 0; }
+    auto operator=(Shader &&other) noexcept -> Shader &
+    {
+        program = other.program;
+        other.program = 0;
+        return *this;
+    };
+
+    ~Shader();
+
+    void bind() const;
+    static void unbind();
+
+    template <typename T>
+    void set_uniform(std::string_view name, T value) const;
+
+private:
+    auto retrieveUniformLocation(std::string_view uniform_name) const -> GLint;
+    static auto parse(const std::filesystem::path &path) -> std::string;
+    static auto compile(std::string_view source, GLenum type) -> GLuint;
+
+    GLuint program;
+    mutable std::unordered_map<std::string, GLint> uniform_location_cache;
+};
+
+struct ShaderLoader
+{
+    using result_type = std::shared_ptr<Shader>;
+    static constexpr std::string_view shader_directory{"data/shaders"};
+
+    auto operator()(std::string_view name) -> result_type
+    {
+        return std::make_shared<Shader>(name, shader_directory);
+    }
+};