Implemented Skybox support

- Skybox class logic
- Cubemap with OpenGL implementation
- Skybox rendering at last stage in the first render pass
- Option in Editor to enable Skybox

Author: denyskryvytskyi

Engine/CMakeLists.txt

@@ -33,6 +33,7 @@ set(ENGINE_HEADERS
 "src/Renderer/RHI/VertexArray.h"
 "src/Renderer/RHI/Texture.h"
 "src/Renderer/RHI/RenderTarget.h"
+"src/Renderer/RHI/Cubemap.h"
 "src/Renderer/Camera.h"
 "src/Renderer/CameraController.h"
 "src/Renderer/OrthographicCameraController.h"
@@ -44,6 +45,7 @@ set(ENGINE_HEADERS
 "src/Renderer/Mesh.h"
 "src/Renderer/RenderTopology.h"
 "src/Renderer/PostProcessor.h"
+"src/Renderer/Skybox.h"
 "src/Platform/Windows/WindowsWindow.h"
 "src/Platform/OpenGL/OpenGLBuffer.h"
 "src/Platform/OpenGL/OpenGLContext.h"
@@ -52,6 +54,7 @@ set(ENGINE_HEADERS
 "src/Platform/OpenGL/OpenGLVertexArray.h"
 "src/Platform/OpenGL/OpenGLTexture.h"
 "src/Platform/OpenGL/OpenGLRenderTarget.h"
+"src/Platform/OpenGL/OpenGLCubemap.h"
 "src/Scene/Entity.h"
 "src/Scene/Component.h"
 "src/Scene/Behavior.h"
@@ -114,13 +117,15 @@ set(ENGINE_SOURCES
 "src/Renderer/Mesh.cpp"
 "src/Renderer/Material.cpp"
 "src/Renderer/PostProcessor.cpp"
+"src/Renderer/Skybox.cpp"
 "src/Platform/OpenGL/OpenGLBuffer.cpp"
 "src/Platform/OpenGL/OpenGLContext.cpp"
 "src/Platform/OpenGL/OpenGLRendererAPI.cpp"
 "src/Platform/OpenGL/OpenGLShader.cpp"
 "src/Platform/OpenGL/OpenGLVertexArray.cpp"
 "src/Platform/OpenGL/OpenGLTexture.cpp"
 "src/Platform/OpenGL/OpenGLRenderTarget.cpp"
+"src/Platform/OpenGL/OpenGLCubemap.cpp"
 "src/Platform/Windows/WindowsInput.cpp"
 "src/Platform/Windows/WindowsWindow.cpp"
 "src/Scene/Behavior.cpp"

Engine/assets/shaders/skybox.frag

@@ -0,0 +1,11 @@
+#version 450 core
+out vec4 FragColor;
+
+in vec3 TexCoords;
+
+uniform samplerCube skybox;
+
+void main()
+{    
+    FragColor = texture(skybox, TexCoords);
+}

Engine/assets/shaders/skybox.vert

@@ -0,0 +1,14 @@
+#version 450 core
+
+layout (location = 0) in vec3 aPos;
+
+out vec3 TexCoords;
+
+uniform mat4 u_ViewProjection;
+
+void main()
+{
+    TexCoords = aPos;
+    vec4 pos = u_ViewProjection * vec4(aPos, 1.0);
+    gl_Position = pos.xyww;
+}

Engine/src/Core/Application.cpp

@@ -202,7 +202,7 @@ void Application::OnWindowResize(const events::WindowResizeEvent& e)
     OnWindowResizeApp();
 }
 
-void Application::UpdateFps(Timer& fpsCounter, const float elapsed, const float elapsedMs)
+void Application::UpdateFps(Timer& fpsCounter, const float elapsed, const float elapsedMs) const
 {
     static float accumTime = 0.0f;
     static float accumTimeMs = 0.0f;

Engine/src/Core/Application.h

@@ -44,22 +44,22 @@ class Application {
     Renderer& GetRenderer() { return m_renderer; }
 
 protected:
-    virtual void OnCreate() {};
-    virtual void OnUpdate(float dt) {};
-    virtual void OnRender(float dt) {};
-    virtual void OnProcessInput(float dt) {};
+    virtual void OnCreate() { };
+    virtual void OnUpdate(float dt) { };
+    virtual void OnRender(float dt) { };
+    virtual void OnProcessInput(float dt) { };
 #if MODULE_EDITOR_ENABLED
-    virtual void OnImguiRender() {};
+    virtual void OnImguiRender() { };
 #endif
-    virtual void OnDestroy() {};
+    virtual void OnDestroy() { };
 
-    virtual void OnWindowResizeApp() {};
+    virtual void OnWindowResizeApp() { };
 
 private:
     void OnWindowClose(const events::WindowCloseEvent& e);
     void OnWindowResize(const events::WindowResizeEvent& e);
 
-    void UpdateFps(Timer& fpsCounter, const float elapsed, const float elapsedMs);
+    void UpdateFps(Timer& fpsCounter, const float elapsed, const float elapsedMs) const;
 
 protected:
     ecs::Entity m_orthoCameraEntity { ecs::INVALID_ENTITY_ID };

Engine/src/Editor/Editor.cpp

@@ -39,6 +39,7 @@ void Editor::OnImGuiRender()
     bool isVSync = window->IsVSync();
     bool isFullScreen = window->IsFullScreen();
     bool isMSAAEnabled = renderer.IsMSAAEnabled();
+    bool isSkyboxEnabled = renderer.IsSkyboxEnabled();
     bool isBlinnPhongEnabled = renderer.IsBlinnPhongEnabled();
 
     // ============ Settings panel ============
@@ -57,6 +58,10 @@ void Editor::OnImGuiRender()
         renderer.EnableMSAA(isMSAAEnabled);
     }
 
+    if (ImGui::Checkbox("Skybox", &isSkyboxEnabled)) {
+        renderer.EnableSkybox(isSkyboxEnabled);
+    }
+
     if (ImGui::Checkbox("Blinn-Phong", &isBlinnPhongEnabled)) {
         renderer.EnableBlinnPhong(isBlinnPhongEnabled);
     }

Engine/src/Events/EventManager.cpp

@@ -6,7 +6,9 @@ EventManager gEventManager;
 
 void EventManager::Shutdown()
 {
+    m_eventsQueue.clear();
     m_subscribers.clear();
+    m_subscribersByEventId.clear();
 }
 
 void EventManager::Subscribe(EventType eventType, UniquePtr<IEventHandlerWrapper>&& handler, EventId eventId)

Engine/src/Platform/OpenGL/OpenGLCubemap.cpp

@@ -0,0 +1,45 @@
+#include "OpenGLCubemap.h"
+
+#include <glad/gl.h>
+
+namespace elv {
+
+OpenGLCubemap::OpenGLCubemap(const std::vector<TextureManager::LoadedTextureInfo>& texturesInfo)
+{
+    // Generate the cubemap texture
+    glCreateTextures(GL_TEXTURE_CUBE_MAP, 1, &m_id);
+
+    // Specify the storage for the cubemap texture
+    glTextureStorage2D(m_id, 1, GL_RGB8, texturesInfo[0].width, texturesInfo[0].height);
+
+    // Upload the texture data for each face of the cubemap
+    for (unsigned int i = 0; i < texturesInfo.size(); ++i) {
+        if (texturesInfo[i].data) {
+            glTextureSubImage3D(
+                m_id,
+                0,                      // Level of detail
+                0, 0, i,                // Offset (x, y, layer)
+                texturesInfo[i].width,  // Width of the face
+                texturesInfo[i].height, // Height of the face
+                1,                      // Depth (1 for single-layer 2D)
+                GL_RGB,                 // Format of input data
+                GL_UNSIGNED_BYTE,       // Data type of input data
+                texturesInfo[i].data    // Pointer to the texture data
+            );
+        }
+    }
+
+    // Set texture parameters using DSA
+    glTextureParameteri(m_id, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTextureParameteri(m_id, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTextureParameteri(m_id, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTextureParameteri(m_id, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTextureParameteri(m_id, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+}
+
+void OpenGLCubemap::Bind()
+{
+    glBindTexture(GL_TEXTURE_CUBE_MAP, m_id);
+}
+
+} // namespace elv

Engine/src/Platform/OpenGL/OpenGLCubemap.h

@@ -0,0 +1,19 @@
+#pragma once
+
+#include "Renderer/RHI/Cubemap.h"
+#include "Resources/TextureManager.h"
+
+namespace elv {
+
+class OpenGLCubemap : public Cubemap {
+public:
+    OpenGLCubemap(const std::vector<TextureManager::LoadedTextureInfo>& texturesInfo);
+
+    virtual void Bind() override;
+
+private:
+    uint32_t m_id { 0 };
+    uint32_t m_slot { 0 };
+};
+
+} // namespace elv

Engine/src/Platform/OpenGL/OpenGLRendererAPI.cpp

@@ -85,6 +85,11 @@ void OpenGLRendererAPI::EnableDepthTesting(bool enabled)
     }
 }
 
+void OpenGLRendererAPI::EnableDepthMask(bool enabled)
+{
+    glDepthMask(enabled ? GL_TRUE : GL_FALSE);
+}
+
 void OpenGLRendererAPI::EnableMSAA(bool enabled)
 {
     if (enabled) {
@@ -120,4 +125,9 @@ void OpenGLRendererAPI::DrawIndexed(const SharedPtr<VertexArray>& vertexArray, c
     glDrawElements(GetTopology(topology), count, GL_UNSIGNED_INT, nullptr);
 }
 
+void OpenGLRendererAPI::DrawArrays(const SharedPtr<VertexArray>& vertexArray, const std::uint32_t verticesAmount, const RenderTopology topology)
+{
+    glDrawArrays(GetTopology(topology), 0, verticesAmount);
+}
+
 } // namespace elv