Java OpenGL, tworzenie tekstury za pomocą FBO.

	//...
	GuiTexture gui1 = new GuiTexture(loader.loadTexture("gui1.png"), new Vector2f(-0.78f, 0.9f), new Vector2f(0.2f, 0.1f));	
	WaterFrameBuffer fbos = new WaterFrameBuffer();
	GuiTexture gui2 = new GuiTexture(fbos.getReflectionTexture(), new Vector2f(0.7f, 0.7f), new Vector2f(0.3f, 0.3f));

	while(!glfwWindowShouldClose(windowHandle)) {
		glClearColor(R, G, B, 1);
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

		fbos.bindReflectionFrameBuffer();
		scene.renderEntites();
		scene.renderTerrains();
		scene.renderGuis(); //RENDEROWANIE SCENY "DO TEKSTURY" NIE DZIAŁA PRAWIDŁOWO
		fbos.unbindCurrentFrameBuffer();

		scene.renderAll(); //RENDEROWANIE SCENY "NA EKRAN" DZIAŁA PRAWIDŁOWO
			
		glfwSwapBuffers(windowHandle);
		glfwPollEvents();
			
	}
	//...

	//...
	public void renderEntites() {
	//Dla wszystkich obiektów typu Entity:
		//...
		glDrawElements(GL_TRIANGLES, texturedModel.getModel().getVertexCount(), GL_UNSIGNED_INT, 0);
		//...
	}
	public void renderTerrains() {
    	//Dla wszystkich obiektów typu Terrain:
       		//...
       		glDrawElements(GL_TRIANGLES, texturedModel.getModel().getVertexCount(), GL_UNSIGNED_INT, 0);
        	//...
	}
	public void renderGuis() {
  	//Dla wszystkich obiektów typu GuiTexture:        
		//...  
		glEnable(GL_BLEND);
		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
		glDisable(GL_DEPTH_TEST);
  
		glDrawArrays(GL_TRIANGLE_STRIP, 0, quad.getVertexCount());              

		glEnable(GL_DEPTH_TEST);
		glDisable(GL_BLEND);
		//...          
	}
	public void renderAll() {
		renderEntites();
		renderTerrains();
		renderGuis();
	}
	//...

public class WaterFrameBuffer {
	 
    protected static final int REFLECTION_WIDTH = 320;
    private static final int REFLECTION_HEIGHT = 180;
     
    protected static final int REFRACTION_WIDTH = 1280;
    private static final int REFRACTION_HEIGHT = 720;
 
    private int reflectionFrameBuffer;
    private int reflectionDepthBuffer;
    private int reflectionTexture;
     
    private int refractionFrameBuffer;
    private int refractionDepthTexture;
    private int refractionTexture;
 
    public WaterFrameBuffer() {//call when loading the game
        initialiseReflectionFrameBuffer();
        initialiseRefractionFrameBuffer();
    }
 
    private void initialiseReflectionFrameBuffer() {
        reflectionFrameBuffer = createFrameBuffer();
        reflectionTexture = createTextureAttachment(REFLECTION_WIDTH,REFLECTION_HEIGHT);
        reflectionDepthBuffer = createDepthBufferAttachment(REFLECTION_WIDTH,REFLECTION_HEIGHT);
        
        if(glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
        	Main.printlnLog(Integer.toString(glCheckFramebufferStatus(GL_FRAMEBUFFER)));
        }
        
        unbindCurrentFrameBuffer();
    }
    private void initialiseRefractionFrameBuffer() {
        refractionFrameBuffer = createFrameBuffer();
        refractionTexture = createTextureAttachment(REFRACTION_WIDTH,REFRACTION_HEIGHT);
        refractionDepthTexture = createDepthTextureAttachment(REFRACTION_WIDTH,REFRACTION_HEIGHT);
        unbindCurrentFrameBuffer();
    }
    
    public void bindReflectionFrameBuffer() {//call before rendering to this FBO
        bindFrameBuffer(reflectionFrameBuffer,REFLECTION_WIDTH,REFLECTION_HEIGHT);
    }
    public void bindRefractionFrameBuffer() {//call before rendering to this FBO
        bindFrameBuffer(refractionFrameBuffer,REFRACTION_WIDTH,REFRACTION_HEIGHT);
    }
    public void unbindCurrentFrameBuffer() {//call to switch to default frame buffer
        glBindFramebuffer(GL_FRAMEBUFFER, 0);
        glViewport(0, 0, Main.getWindowWidth(), Main.getWindowHeight());
    }
 
    public int getReflectionTexture() {//get the resulting texture
        return reflectionTexture;
    }
    public int getRefractionTexture() {//get the resulting texture
        return refractionTexture;
    }
    public int getRefractionDepthTexture(){//get the resulting depth texture
        return refractionDepthTexture;
    }
    public void clean() {
        glDeleteFramebuffers(reflectionFrameBuffer);
        glDeleteTextures(reflectionTexture);
        glDeleteRenderbuffers(reflectionDepthBuffer);
        glDeleteFramebuffers(refractionFrameBuffer);
        glDeleteTextures(refractionTexture);
        glDeleteTextures(refractionDepthTexture);
    } 
    
    private void bindFrameBuffer(int frameBuffer, int width, int height){
        glBindTexture(GL_TEXTURE_2D, 0);//To make sure the texture isn't bound
        glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);
        glViewport(0, 0, width, height);
    }
    private int createFrameBuffer() {
        int frameBuffer = glGenFramebuffers();
        //generate name for frame buffer
        glBindFramebuffer(GL_FRAMEBUFFER, frameBuffer);
        
        //create the framebuffer
        glDrawBuffer(GL_COLOR_ATTACHMENT0);
        //indicate that we will always render to color attachment 0
        return frameBuffer;
    }
    private int createTextureAttachment(int width, int height) {
        int texture = glGenTextures();
        glBindTexture(GL_TEXTURE_2D, texture);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height,
                0, GL_RGB, GL_UNSIGNED_BYTE, (ByteBuffer) null);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, texture, 0);
        return texture;
    }
    private int createDepthTextureAttachment(int width, int height){
        int texture = glGenTextures();
        glBindTexture(GL_TEXTURE_2D, texture);
        glTexImage2D(GL_TEXTURE_2D, 0, GL_DEPTH_COMPONENT32, width, height,
                0, GL_DEPTH_COMPONENT, GL_FLOAT, (ByteBuffer) null);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glFramebufferTexture(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT,
                texture, 0);
        return texture;
    }
    private int createDepthBufferAttachment(int width, int height) {
        int depthBuffer = glGenRenderbuffers();
        glBindRenderbuffer(GL_RENDERBUFFER, depthBuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, width,
                height);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT,
                GL_RENDERBUFFER, depthBuffer);
        return depthBuffer;
    }
   
}

		fbos.bindReflectionFrameBuffer();
		scene.renderEntites();    //OBIEKTY NIE SĄ WIDOCZNE W GUI2 - CZARNY EKRAN
		scene.renderTerrains();  //OBIEKTY NIE SĄ WIDOCZNE W GUI2 - CZARNY EKRAN
		scene.renderGuis();       //OBIEKTY SĄ WIDOCZNE W GUI2
		fbos.unbindCurrentFrameBuffer();

		scene.renderAll();    //RENDEROWANIE WSZYSTKICH ELEMENTÓW "NA EKRAN" DZIAŁA PRAWIDŁOWO