Render to texture implemented - need to flip the resulting image vertically

docs/Tasks.todo

@@ -11,13 +11,15 @@ Core:
         ✔ Add a new class for font loading/management and text rendering @done (9/7/2021, 3:57:08 PM)
         ✔ Make the text renderer smarter about breaking up words on multiple lines @low @done (9/8/2021, 2:23:03 PM)
         ✔ Implement the Image creation methods @done (9/9/2021, 2:50:20 PM)
+        ☐ Implement Render to Texture
 
         
         GUI:
             ✔ Dear ImGui class with basic initialization @done (9/10/2021, 1:42:19 PM)
             ✔ Debug log window @done (9/10/2021, 4:44:48 PM)
-            ☐ Add key to show debug log window
+            ✔ Add key to show debug log window @done (9/13/2021, 6:47:44 PM)
             ☐ Add checkboxes to disable log categories and levels
+            ☐ Add LUA Console window
 
     Input:
         ✔ Port over the Element2D input system and adjust it to use glfw @done (9/8/2021, 8:20:07 PM)
@@ -68,3 +70,7 @@ Editor:
 
 Asset Pipeline:
     ☐ Read through the contents folder and generate asset files in a custom format (useable by the engine)
+
+Tester:
+    - A special class that is used to unit-test features of the engine
+    

scripts/cmconfig.bat

@@ -3,4 +3,4 @@ REM This script expects to be run from the parent directory
 REM ex. scripts/cmconfig.bat
 @echo on
 
-cmake -DGLFW_BUILD_DOCS=OFF -B build/ -S . -G "Visual Studio 16 2019" -A x64
+cmake -Wno-dev -DGLFW_BUILD_DOCS=OFF -B build/ -S . -G "Visual Studio 16 2019" -A x64

src/core/core.cpp

@@ -225,6 +225,14 @@ namespace lunarium
 
             // Update game state
 
+             mpGraphics->BeginDraw(RenderTarget::RT_IMAGE);
+            
+             // DEBUG: Graphics tests
+             mpGraphics->DrawFilledEllipse(glm::vec2(600, 300), glm::vec2(100, 150), Color(1.0f, 0.0f, 1.0f, 1.0f), 100);
+             mpGraphics->DrawString("This is a test of the text renderer!", Rectangle(100, 200, width, 300), 
+                                     Color(0.0f, 1.0f, 1.0f, 1.0f), 0.5f, mpGraphics->DefaultFont());
+             Image* pImage = mpGraphics->EndDraw();
+
             // Render
             mGUI.NewFrame();
             mpGraphics->BeginDraw();
@@ -233,13 +241,12 @@ namespace lunarium
             // mGUI.ShowDemoWindow();
             LogGui::GetInstance().Show();
 
-            // DEBUG: Graphics tests
-            mpGraphics->DrawFilledEllipse(glm::vec2(600, 300), glm::vec2(100, 150), Color(1.0f, 0.0f, 1.0f, 1.0f), 100);
-            mpGraphics->DrawString("This is a test of the text renderer!", Rectangle(100, 200, width, 300), 
-                                    Color(0.0f, 1.0f, 1.0f, 1.0f), 0.5f, mpGraphics->DefaultFont());
+            mpGraphics->DrawImage(*pImage, glm::vec2(0.0f, 0.0f), Color(1.0f, 1.0f, 1.0f, 1.0f));
 
             mGUI.EndFrame();
             mpGraphics->EndDraw();
+
+           // delete pImage;
         }
     }
 }

src/graphics/definitions.h

@@ -0,0 +1,23 @@
+/******************************************************************************
+*	File		-	definitions.h
+*	Author		-	Joey Pollack
+*	Date		-	2021/09/14 (y/m/d)
+*	Mod Date	-	2021/09/14 (y/m/d)
+*	Description	-	Common graphics definitions 
+******************************************************************************/
+
+#ifndef DEFINITIONS_H_
+#define DEFINITIONS_H_
+
+namespace lunarium
+{
+    enum ImageFormat
+	{
+		RGB,
+		RGBA,
+		BGR,
+		BGRA
+	};
+}
+
+#endif     // DEFINITIONS_H_

src/graphics/gui/logGui.cpp

@@ -43,7 +43,7 @@ namespace lunarium
     ////////////////////////////////////////////////////////////
     LogGui* LogGui::mpInstance = nullptr;
     LogGui::LogGui()
-        : mbShow(true), mListener(this), mbOglDebug(false)
+        : mbShow(true), mListener(this), mbOglDebug(false), mbInfoVerbose(false)
     {
 
     }
@@ -83,14 +83,18 @@ namespace lunarium
             ImGui::End();
             return;
         }
-
+        ImGui::BeginChild("Message Types", ImVec2(0.0f, 20.0f));
         ImGui::Checkbox("OGL_DEBUG", &mbOglDebug);
+        ImGui::SameLine();
+        ImGui::Checkbox("INFO_VERBOSE", &mbInfoVerbose);
+        ImGui::EndChild();
         ImGui::Separator();
         ImGui::BeginChild("scrolling", ImVec2(0, 0), false, ImGuiWindowFlags_HorizontalScrollbar);
         ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0, 0));
         for (int i = 0; i < mMsgHistory.size(); i++)
         {
-            if (mMsgHistory[i].find("[OGL_DEBUG]") != std::string::npos && !mbOglDebug)
+            if ((mMsgHistory[i].find("[OGL_DEBUG]") != std::string::npos && !mbOglDebug)
+            || (mMsgHistory[i].find("[INFO_VERBOSE]") != std::string::npos && !mbInfoVerbose))
             {
                 continue;
             }

src/graphics/gui/logGui.h

@@ -48,6 +48,7 @@ namespace lunarium
         GuiListener mListener;
 
         bool mbOglDebug;
+        bool mbInfoVerbose;
 
     private:
         LogGui();

src/graphics/igraphics.h

@@ -10,6 +10,7 @@
 #ifndef IGRAPHICS_H_
 #define IGRAPHICS_H_
 
+#include "definitions.h"
 #include <utils/types.h>
 #include <utils/opRes.h>
 
@@ -19,12 +20,12 @@ namespace lunarium
 	class Window;
 	class Image;
 
-	enum ImageFormat
+	
+
+	enum RenderTarget
 	{
-		RGB,
-		RGBA,
-		BGR,
-		BGRA
+		RT_WINDOW,
+		RT_IMAGE
 	};
 
 	class IGraphics
@@ -39,8 +40,10 @@ namespace lunarium
 
 		virtual void ResizeCanvas() = 0;
 
-		virtual void BeginDraw() = 0;
-		virtual void EndDraw() = 0;
+		// If render target is set to image the image will be the same
+		// size as the window
+		virtual void BeginDraw(RenderTarget rt = RenderTarget::RT_WINDOW) = 0;
+		virtual Image* EndDraw() = 0;
 
 	public:	// 
 
@@ -73,6 +76,7 @@ namespace lunarium
 		bool mbIsInit;
 		int mDefaultFont;
 		Color mClearColor;
+		Image* mpFBTexture;
 	};
 }
 

src/graphics/image.cpp

@@ -8,9 +8,49 @@
 ******************************************************************************/
 
 #include "image.h"
+#include <cstring>
 
 namespace lunarium
 {
+	
+	Image::Image()
+		: mRawData(nullptr), mRawDataSize(0), mWidth(0), mHeight(0)
+	{
+	}
+
+	Image::~Image()
+	{
+		delete[] mRawData;
+		mRawData = nullptr;
+	}
+
+	
+	Image::Image(const Image& rhs)
+		: mRawData(nullptr), mRawDataSize(0), mWidth(0), mHeight(0)
+	{
+		*this = rhs;
+	}
+
+	const Image& Image::operator=(const Image& rhs)
+	{
+		if (this == &rhs)
+		{
+			return *this;
+		}
+
+		FreeRawData();
+		mGLTextureID = rhs.mGLTextureID;
+		mFormat = rhs.mFormat;
+		mWidth = rhs.mWidth;
+		mHeight = rhs.mHeight;
+		mRawDataSize = rhs.mRawDataSize;
+
+		mRawData = new unsigned char[mRawDataSize];
+		memcpy(mRawData, rhs.mRawData, mRawDataSize);
+
+		return *this;
+	}
+
 	unsigned int  Image::GetGLTextureID() const
 	{
 		return mGLTextureID;
@@ -26,23 +66,16 @@ namespace lunarium
 		return mHeight;
 	}
 
-	void Image::FreeRawData()
-	{
-		delete[] mRawData;
-		mRawData = nullptr;
-
-		mRawDataSize = 0;
-	}
-
-	Image::Image()
-		: mRawData(nullptr), mRawDataSize(0), mWidth(0), mHeight(0)
+	ImageFormat Image::GetFormat() const
 	{
+		return mFormat;
 	}
 
-	Image::~Image()
+	void Image::FreeRawData()
 	{
 		delete[] mRawData;
 		mRawData = nullptr;
-	}
 
+		mRawDataSize = 0;
+	}
 }

src/graphics/image.h

@@ -10,6 +10,7 @@
 #ifndef IMAGE_H_
 #define IMAGE_H_
 
+#include "definitions.h"
 
 namespace lunarium
 {
@@ -23,6 +24,7 @@ namespace lunarium
 		unsigned int GetGLTextureID() const;
 		int GetWidth() const;
 		int GetHeight() const;
+		ImageFormat GetFormat() const;
 
 		void FreeRawData();
 
@@ -30,11 +32,14 @@ namespace lunarium
 
 		Image();
 		~Image();
+		Image(const Image& rhs);
+		const Image& operator=(const Image& rhs);
 		
 		unsigned char* mRawData;
 		int mRawDataSize;
 		int mWidth;
 		int mHeight;
+		ImageFormat mFormat;
 
 		unsigned int mGLTextureID;
 	};

src/graphics/opengl/glGraphics.cpp

@@ -58,7 +58,8 @@ namespace lunarium
         }
 
         mpWindow = pWindow;
-		ResizeCanvas();
+		mpFBTexture = new Image;
+		ResizeCanvas();	// Also calls InitTextureFrameBuffer
 
 		glEnable(GL_BLEND);
 		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
@@ -104,26 +105,59 @@ namespace lunarium
     void OglGraphics::ResizeCanvas()
     {
         // Get viewport size from glfw window
-        int width = 0;
-        int height = 0;
-        glfwGetFramebufferSize(mpWindow->GetWindow(), &width, &height);
+        glfwGetFramebufferSize(mpWindow->GetWindow(), &mFBWidth, &mFBHeight);
         
-		glViewport(0, 0, width, height);
-		mProjection = glm::ortho(0.0f, (GLfloat)width, (GLfloat)height, 0.0f, -1.0f, 1.0f);
+		glViewport(0, 0, mFBWidth, mFBHeight);
+		mProjection = glm::ortho(0.0f, (GLfloat)mFBWidth, (GLfloat)mFBHeight, 0.0f, -1.0f, 1.0f);
 
 		Logger::Log(LogCategory::GRAPHICS, LogLevel::INFO_VERBOSE, 
-		 	"glViewport set to %d, %d", width, height);
+		 	"glViewport set to %d, %d", mFBWidth, mFBHeight);
+
+		InitTextureFrameBuffer();
     }
     
 
-    void OglGraphics::BeginDraw()
+    void OglGraphics::BeginDraw(RenderTarget rt)
+    {
+		mRT = rt;
+
+		if (mRT == RenderTarget::RT_IMAGE)
 		{
+			glBindFramebuffer(GL_FRAMEBUFFER, mFBO);
+		}
+
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     }
     
-    void OglGraphics::EndDraw()
+    Image* OglGraphics::EndDraw()
+    {
+		if (mRT == RenderTarget::RT_IMAGE)
+		{
+			glBindFramebuffer(GL_FRAMEBUFFER, 0);
+			glBindTexture(GL_TEXTURE_2D, mpFBTexture->mGLTextureID);
+
+			// Buffer width and height (in pixels) is the same as the screen size
+			// Need to multiply these by the number bytes per pixel
+			int bufferSize = mFBWidth * mFBHeight * 4; // NOTE: Assuming 4 channels for now
+			unsigned char* buffer = new unsigned char[bufferSize];
+			glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_UNSIGNED_BYTE, (void*)buffer);
+
+			mpFBTexture->FreeRawData();
+			mpFBTexture->mWidth = mFBWidth;
+			mpFBTexture->mHeight = mFBHeight;
+			mpFBTexture->mRawData = buffer;
+			mpFBTexture->mRawDataSize = bufferSize;
+			mpFBTexture->mFormat = ImageFormat::RGBA;
+
+			// return a copy of the image
+			return new Image(*mpFBTexture);
+		}
+		else
 		{
         	mpWindow->SwapBuffers();
+			return nullptr;
+		}
+
     }
     ////////////////////////////////////////////////////////////
 
@@ -274,11 +308,13 @@ namespace lunarium
 		glm::mat4 trans = glm::translate(id, pos);
 		trans = glm::scale(trans, glm::vec3(destination.Width, destination.Height, 1.0f));
 
+		mImageShader.MakeActive();
+
 		// float widthDiff = image.GetWidth() - source.Width;
 
 		// if (source.Width == image.GetWidth() && source.Height == image.GetHeight())
 		// {
-        //     mImageShader.MakeActive();
+           
         //     mImageShader.SetUniformf("uvManip", { 1.0f, 0.0f, 1.0f, 0.0f });	// No uv Manipulation
         //     mImageShader.SetUniformMatrix("model", 1, glm::value_ptr(trans));
         //     mImageShader.SetUniformMatrix("projection", 1, glm::value_ptr(mProjection));
@@ -293,6 +329,8 @@ namespace lunarium
             float yScale = source.Height / image.GetHeight();
             float yOffset = source.Top / image.GetHeight();
 
+			Logger::Log(LogCategory::GRAPHICS, LogLevel::INFO_VERBOSE, "uvManip Values: %f, %f, %f, %f", xScale, xOffset, yScale, yOffset);
+
             mImageShader.SetUniformf("uvManip", { xScale, xOffset, yScale, yOffset });
             mImageShader.SetUniformMatrix("model", 1, glm::value_ptr(trans));
             mImageShader.SetUniformMatrix("projection", 1, glm::value_ptr(mProjection));
@@ -432,15 +470,6 @@ namespace lunarium
 		}
     }
     
-    void OglGraphics::InitTextSystem()
-    {
-        // TODO: Check to see if Dear ImGui can be used to render text
-        //       If it can render text on the app window and doesn't need
-        //       to render onto one of it's own windows then it should work.
-        //       If not add FreeType to the project and put the text rendering
-        //       into it's own class.
-    }
-    
     void OglGraphics::InitShapeSystem()
     {
         // Create rectangle buffers
@@ -474,4 +503,39 @@ namespace lunarium
 			Logger::Log(LogCategory::GRAPHICS, LogLevel::WARNING, "Unable to build shape shader program.");
 		}
     }
+
+	void OglGraphics::InitTextureFrameBuffer()
+	{
+		// Frame buffer
+		glGenFramebuffers(1, &mFBO);
+		glBindFramebuffer(GL_FRAMEBUFFER, mFBO);
+
+		// Texture
+		glGenTextures(1, &mpFBTexture->mGLTextureID);
+		glBindTexture(GL_TEXTURE_2D, mpFBTexture->mGLTextureID);
+		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, mFBWidth, mFBHeight, 0, GL_RGB, GL_UNSIGNED_BYTE, nullptr);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+		glBindTexture(GL_TEXTURE_2D, 0);
+
+		// Attach texture
+		glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, mpFBTexture->mGLTextureID, 0);
+
+		// Render Buffer for depth/stencil testing
+		glGenRenderbuffers(1, &mRBO);
+		glBindRenderbuffer(GL_RENDERBUFFER, mRBO);
+		glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH24_STENCIL8, mFBWidth, mFBHeight);
+		glBindRenderbuffer(GL_RENDERBUFFER, 0);
+
+		// Atach the render buffer
+		glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_RENDERBUFFER, mRBO);
+
+
+		if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+		{
+			Logger::Log(LogCategory::GRAPHICS, LogLevel::WARNING, "Unable to initialize framebuffer for rendering to a texture");
+		}
+
+		glBindFramebuffer(GL_FRAMEBUFFER, 0);
+	}
 }

src/graphics/opengl/glGraphics.h

@@ -31,8 +31,11 @@ namespace lunarium
 
 		virtual void ResizeCanvas();
 
-		virtual void BeginDraw();
-		virtual void EndDraw();
+		virtual void BeginDraw(RenderTarget rt = RenderTarget::RT_WINDOW);
+
+		/// The image returned by this method is dynamic
+		/// and needs to be cleaned up
+		virtual Image* EndDraw();
 
 	public:	// 
 
@@ -64,6 +67,15 @@ namespace lunarium
         Window* mpWindow;
 		glm::mat4 mProjection;
 
+		// Viewport/Framebuffer width and height
+		int mFBWidth;
+		int mFBHeight;
+
+		// Objects for rendering to texture
+		unsigned int mFBO;
+		unsigned int mRBO; // for depth and stencil
+		RenderTarget mRT;
+
 		// TEXT
 		glText mText;
         
@@ -83,8 +95,8 @@ namespace lunarium
     private:    // Helper Initializers
     	void InitDebugMsgSystem();
 		void InitImageSystem();
-		void InitTextSystem();
 		void InitShapeSystem();
+		void InitTextureFrameBuffer();
 
 	private: // Helper methods